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venturabananas
11-18-2012, 12:21 AM
You get a lot of bunches of bananas!

http://www.bananas.org/gallery/watermark.php?file=51391&size=1 (http://www.bananas.org/gallery/showphoto.php?photo=51391&ppuser=7760)

This is my neighbor's "Namwah" (Pisang Awak) mat. She doesn't remove pups or fertilize. You can't see them all in this photo, but there's 13 bunches hanging in this single mat that started from one plant several years ago. Would she have bigger bananas if she removed pups? Probably. But she'll have a steady supply of delicious bananas for months instead of a few big bunches that ripen all at once. Since she's not selling them, having a steady stream of tasty bananas rather than a few overwhelming bonzanas of big fruit works just fine for her.

So think about what you want, and then decide what you're going to do about removing pups.

Note that this mat isn't surrounded by other tall plants, so it gets good sun on all sides. If it was shaded by other mats, you'd probably get a different result.

Dalmatiansoap
11-18-2012, 03:08 AM
Thats sweet sight! Plants are huge!
:nanadrink:

Yuri Barros
11-18-2012, 04:42 AM
Amazing.............

momoese
11-18-2012, 10:44 AM
That what my HA and Jamaican Red stands used to look like. The problem for me was the wind breaking the fruiting plants every year and the stands getting close to lifting our new fence.

At some point she will have to remove the inner circle of plants because they will start growing above ground where they will not be able to support fruit bunches nor will they get adequate water or nutrients needed to make healthy plants and bunches.

PR-Giants
11-18-2012, 11:39 AM
At some point she will have to remove the inner circle of plants because they will start growing above ground where they will not be able to support fruit bunches nor will they get adequate water or nutrients needed to make healthy plants and bunches.

Actually she can solve all those potential problems by just shoveling some soil into the center.
My guess would be she probably is already doing something, even if it is only adding some yard waste to the center.
Having a compost pile in the center of a mat or a group of plants works great, feeds and maintains a proper moisture level all at the same time.

momoese
11-18-2012, 11:44 AM
Actually she can solve all those potential problems by just shoveling some soil into the center.
My guess would be she probably is already doing something, even if it is only adding some yard waste to the center.
Having a compost pile in the center of a mat or a group of plants works great, feeds and maintains a proper moisture level all at the same time.

I can see that method working in a more tropical area but where Mark lives it gets too cold and wet to compost and could end up turning into black slime.

cheson74
11-18-2012, 11:45 AM
My Ice Cream matt was getting that way so i started removing pups. Some of the pups were 11+ feet tall. :ha::ha: I wasnt concerned about having lots of bunches. Lack of space is always an issue in Hawaii.

Thanks for sharing.

venturabananas
11-18-2012, 12:14 PM
That what my HA and Jamaican Red stands used to look like. The problem for me was the wind breaking the fruiting plants every year and the stands getting close to lifting our new fence.

At some point she will have to remove the inner circle of plants because they will start growing above ground where they will not be able to support fruit bunches nor will they get adequate water or nutrients needed to make healthy plants and bunches.

She hasn't lost any to wind, probably mainly for two reasons: these plants aren't all that tall (none over 11' of p-stem, despite what it looks like in the photo), and Pisang Awak varieties seem to be very well anchored.

They are starting to get higher in the middle, and the plants in the middle are getting smaller and making smaller bunches. But they are still producing, with no maintenance. I'm not sure how long this mat has been going, at least 4-5 years. It'll be interesting to see how the mat looks in a few more years.

venturabananas
11-18-2012, 12:19 PM
Actually she can solve all those potential problems by just shoveling some soil into the center.
My guess would be she probably is already doing something, even if it is only adding some yard waste to the center.
Having a compost pile in the center of a mat or a group of plants works great, feeds and maintains a proper moisture level all at the same time.

No, seriously, she isn't doing anything other than watering them. We have very heavy clay soil that doesn't get leached of nutrients or dry out easily. Eventually, this mat will have to run out of nutrients, but not yet.

The compost pile in the center of the mat would be good for the non-winter months here, but like Mitchel says, it would be probably be disaster during our cool, wet winters, when banana roots and corms tend to rot.

PR-Giants
11-18-2012, 12:40 PM
No, seriously, she isn't doing anything other than watering them. We have very heavy clay soil that doesn't get leached of nutrients or dry out easily. Eventually, this mat will have to run out of nutrients, but not yet.

The compost pile in the center of the mat would be good for the non-winter months here, but like Mitchel says, it would be probably be disaster during our cool, wet winters, when banana roots and corms tend to rot.

I can accept that cold and wet could rot the corm, but I'm more curious about the feeder roots.
The best medium for growing long healthy feeder roots in Puerto Rico is having enough black or brown slime "semi-composted material".
That is the main reason my plants have 20'-30' roots. I can say for certain that roots here grow much faster in slime than in soil.
They will not even rot after a year of being in standing water.

Have you ever actually seen feeder roots rotting?

momoese
11-18-2012, 01:45 PM
Quite few years back I though it would be a good idea to shred banana plants and spread them about 6 inches thick all through the banana garden in hopes it would keep the soil warm. Then we had quite a bit of rain and cold temps. Come early spring I decided to see what the soil looked like because the plants were not growing. It was black slime with no signs of life at all. All the cut down pseudo-stems and corms were rotting and smelled like rotting fish. It took me weeks to clear all the mess and get the soil somewhat dried out and back to normal. I continued to remove rot from plants well into spring. I won't be doing that again!

PR-Giants
11-18-2012, 02:33 PM
Quite few years back I though it would be a good idea to shred banana plants and spread them about 6 inches thick all through the banana garden in hopes it would keep the soil warm. Then we had quite a bit of rain and cold temps. Come early spring I decided to see what the soil looked like because the plants were not growing. It was black slime with no signs of life at all. All the cut down pseudo-stems and corms were rotting and smelled like rotting fish. It took me weeks to clear all the mess and get the soil somewhat dried out and back to normal. I continued to remove rot from plants well into spring. I won't be doing that again!

Wow, I have been using that same technique for 15 years and it works great here.
My entire growing strategy is based on this technique and I have not been able to find anything that works better.
My goal is a minimum of 6" after being compacted, the crushed pseudostems also works perfectly.
It seems a little odd that the climate makes that much of a difference, but that explains quite a bit about the differences with water and nutrients and even why you guys seemed satisfied with 5'-10' feeder roots.

At least now you know you had a great idea, just the wrong climate.

Thanks for the info, Mitchel.

LilRaverBoi
11-18-2012, 03:01 PM
Thank you for posting this. There have been so many threads about whether or not to remove pups, and this does a great job of summing up one of the options.

PR-Giants
11-18-2012, 03:05 PM
Mitchel, I don't know the depth that you used or even if it will make a difference but I only have about 2"-3" of sand covering the material and it feels like you're walking on a mattress.
Posting a photo of my ground will not be of much use, but I do have photos of an above ground technique which is basically identical except for the fact it is vertical and not horizontal.
I have been able to grow the roots taller than the tops of the leaves, a little crazy but I was curious.

momoese
11-18-2012, 05:56 PM
Mitchel, I don't know the depth that you used or even if it will make a difference but I only have about 2"-3" of sand covering the material and it feels like you're walking on a mattress.
Posting a photo of my ground will not be of much use, but I do have photos of an above ground technique which is basically identical except for the fact it is vertical and not horizontal.
I have been able to grow the roots taller than the tops of the leaves, a little crazy but I was curious.

I placed the shredded/chopped bananas on top of clay soil that had been amended with composted material for several years. Even after all that amending it's still hard packed clay just a few feet down so it can only handle just so much water, especially being on relatively flat ground where there is little runoff. Add some cold temps and you have a real mess on your hands!

As for feeder roots are you talking about the bright furry white ones just under the surface of the soil or compost?

venturabananas
11-18-2012, 06:42 PM
I could see how Keith's approach might work great in the tropics, but it just doesn't translate to areas where the bananas are standing in cold, damp soil. Under those conditions, the plants really aren't growing at all and they are prone to fungal rot. I have definitely seen rotted roots and corms in my yard under those conditions, like Mitchel mentioned. That's one of the risks of growing a tropical plant in non-tropical conditions.

venturabananas
11-18-2012, 06:49 PM
... the inner circle of plants ... will start growing above ground...

I saw a funny example of this near my house. There's a huge mat of Musa balbisiana in a narrow, concrete enclosed space in a parking lot. It's maybe 15' x 4'. All of the plants in it are now at least 1-2' above ground level. But they're not falling over, for whatever reason.

PR-Giants
11-18-2012, 06:52 PM
As for feeder roots are you talking about the bright furry white ones just under the surface of the soil or compost?

Yes


I placed the shredded/chopped bananas on top of clay soil that had been amended with composted material for several years. Even after all that amending it's still hard packed clay just a feet down so it can only handle just so much water, especially being on relatively flat ground where there is little runoff. Add some cold temps and you have a real mess on your hands!


It sounds like your corm rotted then the roots died, I've never seen roots rot before the corm starts to rot. The roots will thrive with high moisture.

Maybe the problem was as a simple as "you shredded/chopped" and I crushed.
Crushing will break all the water cells which allows the feeder roots to enter the fibers.
A crushed pseudostem will breakdown much quicker than a chopped one.

As for hard packed clay, my ground is like concrete. I don't dig, I drill a hole for the corm and build my soil above the existing surface level.
Most of my experimenting is done on slabs of concrete, if it works on concrete it will work in field.

It is such a perfect method for growing bananas, I'm disappointed it doesn't work on the mainland.

PR-Giants
11-18-2012, 07:05 PM
I could see how Keith's approach might work great in the tropics, but it just doesn't translate to areas where the bananas are standing in cold, damp soil. Under those conditions, the plants really aren't growing at all and they are prone to fungal rot. I have definitely seen rotted roots and corms in my yard under those conditions, like Mitchel mentioned. That's one of the risks of growing a tropical plant in non-tropical conditions.

The corm and the feeder roots are two completely different parts and need to be treated differently.

I'd like to know if you think this set up would work in your climate.
It is simple and works great, I don't use it because it is ugly and my other methods work better. In drought conditions this method can be used successfully with very little water.

5 Gallon Bucket filled with fresh grass clippings and compacted with a potted plant.
As it compacts more clippings are added and it can be watered through the grass.
You should be able to clearly see the roots.
oct 23
http://www.bananas.org/gallery/watermark.php?file=51396&size=1 (http://www.bananas.org/gallery/showphoto.php?photo=51396)
oct 23
http://www.bananas.org/gallery/watermark.php?file=51395&size=1 (http://www.bananas.org/gallery/showphoto.php?photo=51395)

32 Gallon version
aug 25
http://www.bananas.org/gallery/watermark.php?file=51393 (http://www.bananas.org/gallery/showphoto.php?photo=51244)

oct 24
http://www.bananas.org/gallery/watermark.php?file=51394 (http://www.bananas.org/gallery/showphoto.php?photo=51395)

In a very short period of time these containers become completely filled with feeder roots.
If these containers were stacked 20'-30' tall, they would still become completely filled with roots.
After harvest, I will slice the contents of the containers and post photos of the roots.

By digging an open pit in the center of a group of plants and continually keeping it full of yard waste will achieved the same results and retain more moisture without the ugly view of a barrel.

It is difficult for me to understand why these techniques will not work in California.

I would be surprised if someone could get the roots to rot while maintaining a healthy corm.

This method allows the corm and feeder roots to be treated differently. The roots can enjoy a high moisture environment teeming with macro and micronutrients, while the corm can be located in a sandy well-drained environment.

In Puerto Rico these techniques will quickly establish a huge root base, which in turn will help the plant grow larger in less time and bloom more quickly.

It seems that banana growers stateside have such a short growing period that this method should hasten the time between planting and harvest.

Olafhenny
11-18-2012, 10:04 PM
I can see that method working in a more tropical area but where Mark lives it gets too cold and wet to compost and could end up turning into black slime.

I do not quite see it that way. Where I live (HZ6) it is much colder and the frost during winter
breaks down the fiber, really advancing the decomposition in spring and even during the winter.
My experience is that the compost is broken down much more after the thaw than it was
before the frost

Olafhenny
11-18-2012, 10:19 PM
...It was black slime with no signs of life at all. All the cut down pseudo-stems and corms were rotting and smelled like rotting fish. It took me weeks to clear all the mess and get the soil somewhat dried out and back to normal. I continued to remove rot from plants well into spring. I won't be doing that again!

I would presume, that the problem lies in the slime sealing off all air supply to the roots, a problem,
which would be exacerbated if your native soil is non-porous in the first place. To me that slime
has to be terrific fertilizer.

Case in point: All plants need water to survive, but remaining submerged in it for some time will kill
most of them.

Olafhenny
11-18-2012, 11:09 PM
I placed the shredded/chopped bananas on top of clay soil that had been amended with composted material for several years. Even after all that amending it's still hard packed clay just a few feet down so it can only handle just so much water, especially being on relatively flat ground where there is little runoff. Add some cold temps and you have a real mess on your hands!

As for feeder roots are you talking about the bright furry white ones just under the surface of the soil or compost?


If you want to convert your clay soil into good arable loam, I would recommend mixing
under a 1 inch thick layer each, of peat moss and sand (place the sand on top of the peat moss,
because the former will have the tendency to work itself up) and work that in at least 8 inches
deep. You will love that soil later. Your standard garden tiller will not work deep enough, but
will come in handy later in breaking down the lumps some more afterwards.

One 3.8 cf bale of peat moss covers about 45 sf and 1/2 cubic yard of sand covers about 160
square feet. Because you have already some composted material in place you may get away
with using 1/2 cy of sand and 3 bales of peat moss for an area of 10' x 16'.

A lot of people say 'clay' (quite bad for gardening), when they are really dealing with silt (not
so bad). There is an easy way of telling the two apart: You knead a small piece into a ball,
put it into a container with water and leave it sit over night. If the next morning it is still a ball
and does not fall apart when lightly pressed, then you have indeed clay. If it has dissolved into
a little pile of dirt or falls apart easily it is silt. You should make sure that you get some of the
original stuff without compost mixed in for a reliable result.

In either case the above will work, - just a lot better with silt :)

Nicolas Naranja
11-19-2012, 01:48 PM
You get a lot of bunches of bananas!

So think about what you want, and then decide what you're going to do about removing pups.

Note that this mat isn't surrounded by other tall plants, so it gets good sun on all sides. If it was shaded by other mats, you'd probably get a different result.

If you just have one mat of bananas, this is probably the way to go about it. If you have lots of different ones it is best to keep the suckers under control. I have a planting behind my house that it spaced for 800 plants per acre and it requires a lot more management than my larger planting which is only 200 plants per acre. It also depends a lot on your disease conditions, natural fertility, and water availability. In the Florida sands, you might not get much out of a mat like that.

Nicolas Naranja
11-19-2012, 01:56 PM
Wow, I have been using that same technique for 15 years and it works great here.
My entire growing strategy is based on this technique and I have not been able to find anything that works better.
My goal is a minimum of 6" after being compacted, the crushed pseudostems also works perfectly.
It seems a little odd that the climate makes that much of a difference, but that explains quite a bit about the differences with water and nutrients and even why you guys seemed satisfied with 5'-10' feeder roots.

At least now you know you had a great idea, just the wrong climate.

Thanks for the info, Mitchel.

More rain and more heat make all the difference in the world. Even here in Florida, during the winter things slow down and vegetation doesn't break down. What type of grass are you using, that may also play a role.

Bananaman88
11-19-2012, 04:14 PM
I would presume, that the problem lies in the slime sealing off all air supply to the roots, a problem,
which would be exacerbated if your native soil is non-porous in the first place. To me that slime
has to be terrific fertilizer.

Case in point: All plants need water to survive, but remaining submerged in it for some time will kill
most of them.





I agree about the lack of air. Lack of oxygen into the soil causes an anaerobic condition (hence the nasty smell) and can also help lead to the root rot if there is too much moisture present.

sunfish
11-19-2012, 04:34 PM
Soil color - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Soil_color)

venturabananas
11-19-2012, 10:00 PM
I'd like to know if you think this set up would work in your climate.

It is difficult for me to understand why these techniques will not work in California.

I would be surprised if someone could get the roots to rot while maintaining a healthy corm.

I honestly don't know if it would work, but my gut reaction is that it wouldn't work over winter because you'd have problems with rot. I think that when we get root rot it is at least in part because the corm is not healthy or at least not happy. When soil temperatures are in the 40's (F) and the soil is wet, banana corms are not happy and prone to rot. That's not to say they invariably will rot, established plants hang in there, but in terms of growth, they practically go into stasis during our relatively mild winter. I've been keeping track of how long it takes new leaves to emerge. For the fast growers, it'll take a month for each new leaf during our winter, and for the slow growing varieties (i.e., the most cold sensitive), it takes 3-4 months for some. I think the differences between California and the tropics for banana growing all boil down to temperature.

cheson74
11-19-2012, 10:04 PM
I cover the base of the bananas with cut leaves, compost and misc green waste and they thrive. However, on an extremely rare night, the temperature might possibly drop to the high 50s during the winter but will warm up to the 70s and 80s during the day. The soil temperature never really drops because there isn't a prolong drop in temperature.

PR-Giants
11-20-2012, 05:04 PM
I cover the base of the bananas with cut leaves, compost and misc green waste and they thrive. However, on an extremely rare night, the temperature might possibly drop to the high 50s during the winter but will warm up to the 70s and 80s during the day. The soil temperature never really drops because there isn't a prolong drop in temperature.

That's actually not a good thing to do, if you live in an area with corm weevils and sigatoka. It will attract weevils and increase the moisture level between the ground and leaves which in turn increases your risk to sigatoka.

At night when the weevils are active the predators have a more difficult time of catching them in the yard waste opposed to a sandy surface.

A better way would simply be to cover the yard waste with a couple inches of sand. This will increase the moisture level below the soil surface while decreases the moisture level between the surface and the leaves.

PR-Giants
11-20-2012, 07:06 PM
From my experience I've learned that a corm should be planted in sandy soil with the fertile soil about a foot away. This will lower the moisture level near the corm and reduce the risk of corm rot. The roots will quickly and easily reach the nutrient rich soil nearby.

I also take this same approach when planting small plants or corm pieces in pots. I first plant in a small pot of sand and when they are ready for a larger pot, I fill the bottom with enough quality soil to maintain the same surface level of the original pot. Next I stuff about 2 inches of semi-composted grass clippings between the root ball and the pot, then fill the remaining space with quality soil.

The reason for adding the grass is twofold. First, it retains moisture well and gives the roots a great medium to grow in. Second, it acts similarly to a rubber O-ring by preventing any water added from running down between the pot and soil. Often times when someone forgets to water, the soil will contract but the grass will not and this will eliminate the need to soak the pots.

sunfish
11-20-2012, 07:20 PM
From my experience I've learned that a corm should be planted in sandy soil with the fertile soil about a foot away. This will lower the moisture level near the corm and reduce the risk of corm rot. The roots will quickly and easily reach the nutrient rich soil nearby.

I also take this same approach when planting small plants or corm pieces in pots. I first plant in a small pot of sand and when they are ready for a larger pot, I fill the bottom with enough quality soil to maintain the same surface level of the original pot. Next I stuff about 2 inches of semi-composted grass clippings between the root ball and the pot, then fill the remaining space with quality soil.

The reason for adding the grass is twofold. First, it retains moisture well and gives the roots a great medium to grow in. Second, it acts similarly to a rubber O-ring by preventing any water added from running down between the pot and soil. Often times when someone forgets to water, the soil will contract but the grass will not and this will eliminate the need to soak the pots.

Sounds good to me

cheson74
11-21-2012, 10:19 AM
The soil here isn't even close to being sandy. It's hard, compacted clay. Without the addition of the green waste and compost, the bananas struggle. They become stunted, fruit bunches are pathetic and are probably more susceptible to disease. I've yet had a single plant hit with BTV or sigatoka. I'm not saying I'm immune to it; just haven't had it with this method of feeding the plants and loosening the soil.

Several of my neighbors, only 50-100 meters away, have had several diseased plants and they don't do a thing with their soil. Such is the life here in Hawaii.

PR-Giants
11-21-2012, 12:30 PM
The soil here isn't even close to being sandy. It's hard, compacted clay. Without the addition of the green waste and compost, the bananas struggle. They become stunted, fruit bunches are pathetic and are probably more susceptible to disease. I've yet had a single plant hit with BTV or sigatoka. I'm not saying I'm immune to it; just haven't had it with this method of feeding the plants and loosening the soil.

Several of my neighbors, only 50-100 meters away, have had several diseased plants and they don't do a thing with their soil. Such is the life here in Hawaii.

It seems as though you may have missed the point I was making, but at least you're lucky to have soil that's problem is only hard compacted clay. You are correct that laying yard waste on top of compacted clay will loosen the soil by increasing the moisture level, but by covering the yard waste with a couple inches of sand or in your case with some compacted clay will further loosen the soil by increasing the moisture level even more.

This is my top soil and laying yard waste on top of it will not loosen it at all.
It needs to be drilled, removed, crushed, amended and then returned, so if I go through that much effort I might as well do it to the best of my ability.

My whole mountain is one solid piece of this, with the exception of some veins of clay. Finding clay is a thrilling experience, it is so much easier to work with and gives be the ability to plant more in less time.

http://www.bananas.org/gallery/watermark.php?file=50570 (http://www.bananas.org/gallery/showphoto.php?photo=50546)

cheson74
11-21-2012, 01:41 PM
You definitely have it rougher than I do! I started out by tilling/pick axing the first 8 inches. I throw more green waste and compost on top and with a combination of an automatic watering system and high temperatures here, it breaks down extremely fast.

PR-Giants
11-21-2012, 01:54 PM
I agree about the lack of air. Lack of oxygen into the soil causes an anaerobic condition (hence the nasty smell) and can also help lead to the root rot if there is too much moisture present.

This is the anaerobic condition you are referring to and it is confirmed by the nasty smell present.

I work very hard to achieve this condition and firmly believe it to be the best environment for growing long healthy feeder roots.

I did not want to disturb the roots too much because they are very fragile, but the deeper I dig into the ground the darker and wetter it appears.

There is a very easy experiment that can be performed to confirm what you are seeing.

Dig a 30 foot trench and fill it with compacted grass clippings.
Then plant a banana near one end and you will be able to see firsthand how it fills with roots.

There could be multiple reasons why this occurs.

One reason could be that a root enters the slime and becomes disorientated and lost. The corm then sends more roots into the slime in an attempt to rescue the lost root and they also become disorientated and this vicious cycle continues until harvest.

Another reason could be that they just prefer this type of environment.

I fully realize that most things written here and elsewhere describe this as a bad environment for growing bananas in the tropics and subtropics.

My intent for posting the photo was only to give you more information and let you make your own decision of what is possible or preferable.

The key to this being successful might be because I keep the corm in dry sandy soil and only the roots are allowed to grow into the slime, but I honestly don't know the answer. I have questioned many of the members here but was mainly met with skepticism and advice on using better growing techniques.

Please keep in mind that I do not use anything else to feed my bananas and have never needed to water them, the grass acts as a sponge in the ground holding the moisture until needed by the banana plant.

Black Slime nov 21
http://www.bananas.org/gallery/watermark.php?file=51418&size=1 (http://www.bananas.org/gallery/showphoto.php?photo=51418)

Olafhenny
11-21-2012, 02:36 PM
Not all nasty smell is due to anaerobic digestion. While exacerbated in anaerobic conditions, all
rotting matter smells to some extend.

Fact is:
• Roots do need air, that is why farmers have since thousands of year submitted to the back
breaking task of hoeing between plants
• Clay, till and to lesser extent silt tend to restrict access of air to the roots and need more
effort at aeration.
• Any addition of slimy liquids will tend to seal off already dense soils completely, while having
only beneficial impact on sufficiently porous soils.
• In the cited example of compacted grass clippings in a trench, analysis will show you, that
there is as much air between even compacted clippings as you find in most porous soils.
• Local conditions must dictate treatment in specific cases

Nicolas Naranja
11-21-2012, 03:06 PM
• In the cited example of compacted grass clippings in a trench, analysis will show you, that there is as much air between even compacted clippings as you find in most porous soils.
• Local conditions must dictate treatment in specific cases



I'll stand by these statements from personal experience after measuring bulk density and air filled porosity of a variety of different substrates. I still want to know what kind of grass you are using. Are you using something like Para Grass

PR-Giants
11-21-2012, 03:09 PM
Not all nasty smell is due to anaerobic digestion. While exacerbated in anaerobic conditions, all
rotting matter smells to some extend.

Fact is:
• Roots do need air, that is why farmers have since thousands of year submitted to the back
breaking task of hoeing between plants
• Clay, till and to lesser extent silt tend to restrict access of air to the roots and need more
effort at aeration.
• Any addition of slimy liquids will tend to seal off already dense soils completely, while having
only beneficial impact on sufficiently porous soils.
• In the cited example of compacted grass clippings in a trench, analysis will show you, that
there is as much air between even compacted clippings as you find in most porous soils.
• Local conditions must dictate treatment in specific cases





Thanks Olaf,

As I stated, I don't know the answer but that doesn't seem to explain why there are more roots under the water.
As you can see my soil doesn't drain too well and those roots have only been underwater for about 8 or 9 months.

http://www.bananas.org/gallery/watermark.php?file=51419&size=1 (http://www.bananas.org/gallery/showphoto.php?photo=51419)

Yuri Barros
11-21-2012, 03:20 PM
Another reason could be that they just prefer this type of environment.




This environement is similar to those wild bananas are founded...............isn´t it............???

Just rotten leaves.........................

Long roots are seen running near soil surface......................and if you add a little bit of soil or dead leaves....................soon you will see long roots running at surface.....................

I think that Bananas like this stuff...............

Olafhenny
11-21-2012, 03:51 PM
Thanks Olaf,

As I stated, I don't know the answer but that doesn't seem to explain why there are more roots under the water.
As you can see my soil doesn't drain too well and those roots have only been underwater for about 8 or 9 months.

My specific experience with bananas is limited to raising some of them for 3 years and to what I
have observed during my visits to the tropics. The latter includes seeing bananas right at the
edges of rice fields on ground just inches above the waterline and only a few feet from the water's
edge. I have posted on this in other threads in this forum, when I thought that undue concern was
voiced about root rot. There was also a lady here posting about raising bananas in pots
completely submerged in water.

We must not discount, that there is a fair amount of air contained in water, which appears to explain,
that anaerobic decomposition happens generally in standing waters of about 4 feet in depth and more.

The concentration of the roots in the “soup” is probably caused by the nutrients contained
therein and the roots reaching for them.

sunfish
11-21-2012, 05:21 PM
How to Grow Houseplants in Water | Rodale News (http://www.rodale.com/easy-houseplants)

Hydroculture: Growing Plants in Water (http://www.guide-to-houseplants.com/growing-plants-in-water.html)

Olafhenny
11-21-2012, 06:46 PM
Thank you, Tony, I will save the URLs of these interesting sites, especially the one on top for
further reference. I am still concerned about how to provide the necessary nutrients with
well- or bottled water, without changing it frequently.



http://www.bananas.org/gallery/watermark.php?file=51420 (http://www.bananas.org/gallery/showphoto.php?photo=51420&ppuser=7269)

I saw the plant in this picture in Vietnam and was intrigued by it, but did not know any plants,
which were suitable. Now, - if I could just find a solution for the nutrient problem

Thanks again,
Olaf

sunfish
11-21-2012, 06:46 PM
Root rot - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Root_rot)

Root Problems on Plants in the Garden and Landscape, HYG-3061-96 (http://ohioline.osu.edu/hyg-fact/3000/3061.html)

Root Rot | Grow Weed Easy (http://www.growweedeasy.com/root-rot-cannabis)

venturabananas
11-21-2012, 07:04 PM
This is the anaerobic condition you are referring to and it is confirmed by the nasty smell present.

Black Slime nov 21
http://www.bananas.org/gallery/watermark.php?file=51418&size=1 (http://www.bananas.org/gallery/showphoto.php?photo=51418)

I think Olaf has hit the nail on the head: standing water does not necessarily lead to anaerobic conditions. The photo above does not show the classic dark black color that would be present (from hydrogen sulfide buildup) if the conditions were actually anaerobic.

sunfish
11-21-2012, 07:40 PM
Water's the Matter-- Lesson Presentation:* Dissolved Oxygen (http://peer.tamu.edu/curriculum_modules/water_quality/module_3/lesson2.htm)

PR-Giants
11-24-2012, 11:34 AM
I think Olaf has hit the nail on the head: standing water does not necessarily lead to anaerobic conditions. The photo above does not show the classic dark black color that would be present (from hydrogen sulfide buildup) if the conditions were actually anaerobic.

I was able to get a professional opinion from the Caguas Botanical Gardens on some samples and all were considered anaerobic, with the samples from the lower levels having more anaerobic bacteria and an abundance of hydrogen sulfide.
It was an interesting conversation and she said to learn more I should research the growing methods of rice paddies in Asia.
I realize it was difficult to make the correct assessment with only the proverbial "tip of the iceberg" type of information.
The photo was a top view of the most recently added clippings, but I did state previously

I did not want to disturb the roots too much because they are very fragile, but the deeper I dig into the ground the darker and wetter it appears.

PR-Giants
11-24-2012, 11:59 AM
I honestly don't know if it would work, but my gut reaction is that it wouldn't work over winter because you'd have problems with rot. I think that when we get root rot it is at least in part because the corm is not healthy or at least not happy. When soil temperatures are in the 40's (F) and the soil is wet, banana corms are not happy and prone to rot. That's not to say they invariably will rot, established plants hang in there, but in terms of growth, they practically go into stasis during our relatively mild winter. I've been keeping track of how long it takes new leaves to emerge. For the fast growers, it'll take a month for each new leaf during our winter, and for the slow growing varieties (i.e., the most cold sensitive), it takes 3-4 months for some. I think the differences between California and the tropics for banana growing all boil down to temperature.

The barrel method should work perfectly in most areas and vastly improve your current growing technique.
I don't think there is any concern that this grass filled barrel would be a source of fungal disease.
I really believe your reasoning is based on myth and misinformation.
The concern over high moisture levels during the colder months can be addressed by simply adding an elevated cover over the barrel.
This method will also give you the opportunity to track root growth in addition to you tracking new leaves emerging.

sandy0225
11-24-2012, 12:00 PM
I grew a pineapple top in one of those beta vases that were popular years ago with the fish in the bottom of it. It grew that way for over two years and then it got some kind of a funk going and it died. Maybe you need a fish...

sunfish
11-24-2012, 12:05 PM
I was able to get a professional opinion from the Caguas Botanical Gardens on some samples and all were considered anaerobic, with the samples from the lower levels having more anaerobic bacteria and an abundance of hydrogen sulfide.
It was an interesting conversation and she said to learn more I should research the growing methods of rice paddies in Asia.
I realize it was difficult to make the correct assessment with only the proverbial "tip of the iceberg" type of information.
The photo was a top view of the most recently added clippings, but I did state previously

UCSB Science Line sqtest (http://scienceline.ucsb.edu/getkey.php?key=760)

sandy0225
11-24-2012, 12:08 PM
I did grow a banana it was a bordelon I think in the pond display for the summer for a couple of years but I took it out every fall because its too cold here to overwinter it outdoors in Indiana. So it was in a pot and very root bound all summer but in 12" of water, and I pulled it out and put it in a saucer in the greenhouse and kept it fairly dry all winter. I eventually felt sorry for it the second fall and I was getting short on bordelons so I divided it and potted up all the pups that fall. I haven't done one that way in the pond since. I do have a bordelon clump in a ceramic 14" pot that was needing so much water all summer that I kept it in a large saucer filled half full of water and fertilizer at all times. So I know they CAN be grown in submerged conditions.

sunfish
11-24-2012, 12:10 PM
rice (http://www.cix.co.uk/~argus/Dreambio/fertilisers%20and%20crops/rice.htm)

venturabananas
11-24-2012, 12:54 PM
The barrel method should work perfectly in most areas and vastly improve your current growing technique.
I don't think there is any concern that this grass filled barrel would be a source of fungal disease.
I really believe your reasoning is based on myth and misinformation.
The concern over high moisture levels during the colder months can be addressed by simply adding an elevated cover over the barrel.
This method will also give you the opportunity to track root growth in addition to you tracking new leaves emerging.

Phytophthora root rot is not myth. Google it and see what you find. I'm not sure whether this fungus is the cause of rotting corms and roots, which can happen to bananas in cold wet soil, but something causes it. I am not concerned about grass as a source of fungal disease. But I would worry that a barrel of cold, wet grass would provide a perfect incubator for fungal disease. My opinion is that a healthy, actively growing plant is much more resistant to diseases of all sorts. The problem in cooler environments is that bananas do not grow actively when it is cool. During these times, they are susceptible to diseases that wouldn't normally cause them problems. You never have those cold, suboptimal condition in PR.

PR-Giants
11-24-2012, 01:21 PM
Oufei (http://www.agroecology.org/Case%20Studies/oufei.html)

Nicolas Naranja
11-24-2012, 05:07 PM
I had kind of suspected that bananas produced aerenchyma in response to waterlogged conditions. Bananas have the ability to pump air down to the roots from the shoots. This would make sense since I've been told that in vietnam the were commonly seen near rice paddies. My Mexican friends tell me that they seemed to grow best near streams.

Anyways I have attached an article about Aerenchyma in bananas.

Olafhenny
11-24-2012, 07:06 PM
Before I got interested in bananas I read somewhere, that a grower, I believe it was in Mexico,
tried to maintain a ground water level of 70 cm (28 inches) below the surface.

He did that, if I remember correctly by maintaining the water level in ditches through and
around his orchard at that level constantly.

PR-Giants
11-26-2012, 12:25 PM
Growing bananas in Mexico.

http://www.eiag.edu.ni/Pwebs/Carreras/FRUTYWEB/CONFERENCIAS%202011/UNIDAD%20II.%20Musaceas/Materiales%20Musaceas/Paquete%20tecnologico%20del%20cultivo%20del%20P%C3%A1tano.pdf

Nicolas Naranja
11-26-2012, 08:01 PM
Wow, this is a great link. If anyone else can read Spanish, go ahead and take the time to download this.

Growing bananas in Mexico.

http://www.eiag.edu.ni/Pwebs/Carreras/FRUTYWEB/CONFERENCIAS%202011/UNIDAD%20II.%20Musaceas/Materiales%20Musaceas/Paquete%20tecnologico%20del%20cultivo%20del%20P%C3%A1tano.pdf

Olafhenny
11-26-2012, 09:20 PM
Unfortunately for us "igloo dwellers' here in the north it is of little use. :ha:

If you can't read Spanish, just copy and dump it into Google Translate (http://translate.google.com/)
Their translation is not always in the best English, to put it mildly, but it is usually
understandable.

They are much better in scientific texts than in ordinary ones :)
I guess those are used more often.

PR-Giants
11-27-2012, 02:51 AM
Wow, this is a great link. If anyone else can read Spanish, go ahead and take the time to download this.

Sorry, I should have mentioned it was in Spanish. I found this page while searching Enano Gigante.

One thing I appreciated was the use of the term "Prácticas de Cultivo" or cultivation practices opposed to "Cultural Practices".

I realize "Cultural Practices" is a very broad term and widely used in the banana world, but local cultivation practices seems more accurate.

When I read "Cultural Practices" my mind tends to go to Religion, Culinary and the Arts.

PR-Giants
11-28-2012, 08:51 PM
I made this post on a different thread, but thought it might also be helpful here.


This is only my opinion and is based on my observation, and I would also like to understand more.
I might be alone on this theory, but believe it can be supported by other posts if you connect the dots.
You can read in the Org how sometimes someone has tossed a corm in a compost pile and it grew.
If it is growing, the roots are probably still connected to the corm and the person stopped turning the pile.
You should also be able to assume it is an active pile, if a viable corm was tossed in for composting.
Knowing that a properly aerated aerobic pile can reach high temperatures and if not turned will go anaerobic with much lower temperatures.
I can't say for certain but I assume the lower temperatures are better suited for the roots to grow in.

I think most of the confusion is in part to how some people define anaerobic bacteria as being "no oxygen" instead of "with little or no oxygen".

Here is some information that might be helpful.

"Anaerobic bacteria, or anaerobes, are bacteria that do not need oxygen to live."

"There are three categories of anaerobic bacteria: obligate, aerotolerant, and facultative. Obligate anaerobes need an oxygen-free environment to live. They cannot grow in places with oxygen, which can sometimes damage and destroy them. Aerotolerant bacteria do not use oxygen to live, but can exist in its presence. Facultative anaerobes use fermentation to grow in places without oxygen, but use aerobic respiration in places with oxygen."

What Is Anaerobic Bacteria? (http://www.wisegeek.com/what-is-anaerobic-bacteria.htm#)

Anaerobic organism - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Anaerobic_organism)


"Composting without oxygen results in fermentation."

"There is enough heat energy liberated in the process to raise the temperature of the putrefying material. In the anaerobic dissolution of the glucose molecule, only about 26 kcal of potential energy per gram of glucose molecules is released compared to 484 to 674 kcal for aerobic decomposition."

"Anaerobic composting may be accomplished in large, well packed stacks or other composting systems. These should contain 40% to 75% moisture, into which little oxygen can penetrate, or 80% to 99% moisture so that the organic material is a suspension in the liquid."

"Both aerobic and anaerobic composting require bacteria. Some bacteria work better in one or the other environment. Compost piles under aerobic conditions may attain a temperature of 140° to 160° F in one to five days depending upon the material and the condition of the composting operation. This temperature can also be maintained for several days before further aeration is needed. The heat necessary to produce and maintain this temperature must come from aerobic decomposition, which requires oxygen. After a period of time, the material will become anaerobic unless it is aerated. There is probably a period between the times when the oxygen is depleted and anaerobic conditions become evident, during which the process is aerobic."

Compost Fundamentals Biology & Chemistry - Anaerobic Fermentation (http://whatcom.wsu.edu/ag/compost/fundamentals/biology_anaerobic.htm)

PR-Giants
11-28-2012, 09:20 PM
Although I have no experience or desire to grow bananas in a colder climate, I'm still curious if the process can be improved or even if the growing period could be expanded.

During the cooler months what is the first trigger for a plant to slow growth, plant temperature above the ground or below?

I've read many times how people here add a heating pad under a pot to promote root growth.

This leads me to believe that a container of wet partially composted organic matter can easily be dried and have air introduced to increase the temperature of the roots through an aerobic process.

momoese
11-28-2012, 11:32 PM
During the cooler months what is the first trigger for a plant to slow growth, plant temperature above the ground or below?



Above

Olafhenny
11-28-2012, 11:39 PM
My experience is limited to Basjoo and Ornata.
Going into my third winter now with the Basjoo I have observed the following:
They keep on growing until frost damages the leaves, although at a slower pace. That may be
due to cooler temperatures, but I tend more toward believing that is has a lot more to do with
daylight hours.

I have here: http://www.bananas.org/f311/need-advice-grow-banana-plant-indoors-14608-2.html in some detail reported
in a sequence of postings of how my Ornatas fared a year ago in waning light conditions, but at
constant temperatures.

That brings me to another observation, though anecdotal as it may be with my limited experience:
Deep rich humus does not appear to help bananas to grow better and bananas in pots or poor
soil appear to grow more pups. I have so far had only soft indications on the latter and had
actually wanted to wait before I voice that observation, which may be skewed by the fact,
that the Ornatas did very poorly outside, while overwhelmed by my 9 feet high Cannas Australia
and the Rhicinus Communis Purple New Zealand in my ‘tropical planter’
(http://www.bananas.org/f8/my-brand-new-tropical-planter-15715.html).*
And because they were overwhelmed I did not notice, that anything was wrong with them until
I transplanted them back into pots inside. While the Pseudo stems either folded or are in rough
shape, they seem to be pupping quite well.

*If you open that, You see on top a picture, which was taken long before the fall ‘wrap up’. You
can see one of the Ornatas just above the petunias, still in reasonable shape and in the
background the larger leaf of a Basjoo. The New Zealand Castor Bean has after that still grown
substantially, thus drowning out the Ornatas. There is also a picture of that available)

venturabananas
11-29-2012, 01:10 AM
During the cooler months what is the first trigger for a plant to slow growth, plant temperature above the ground or below?

I searched for an answer to this in published scientific papers and I couldn't find anything. Perhaps Gabe, who is more familiar with the literature knows the answer. I suspect no one has bothered to figure out the relative effects of air temperature versus soil temperature because in commercial production in the field, they are tightly correlated. Given that growth occurs at the meristem which is at the top of corm, so very close to ground level, I would guess that soil temperatures are more important than air temperatures.

venturabananas
11-29-2012, 01:18 AM
[SIZE="3"]That may be due to cooler temperatures, but I tend more toward believing that is has a lot more to do with daylight hours.

I doubt it has a LOT more to do with daylight hours. I'm sure they are both important -- you need light for photosynthesis, and within reason, more light results in more photosynthesis, and thus more potential growth. But my bananas grow faster in August than in June. There are fewer daylight hours in August than June, but it is warmer in August than June.

caliboy1994
11-29-2012, 01:42 AM
I doubt it has a LOT more to do with daylight hours. I'm sure they are both important -- you need light for photosynthesis, and within reason, more light results in more photosynthesis, and thus more potential growth. But my bananas grow faster in August than in June. There are fewer daylight hours in August than June, but it is warmer in August than June.

That explains why my plants are displaying really slow growth in November, even when conditions for growth are suitable. But I notice that if warm weather during winter is consistent, plants can begin growing again with considerable speed. This year in January we had a warm spell where daytime temperatures were in the high 70s and low 80s, and this lasted for about a week and a half. My Rajapuri put out one or two leaves then, but it took a few days for it to get going. I think that soil temperature would be a very important factor as well.

PR-Giants
11-29-2012, 02:18 AM
I searched for an answer to this in published scientific papers and I couldn't find anything. Perhaps Gabe, who is more familiar with the literature knows the answer. I suspect no one has bothered to figure out the relative effects of air temperature versus soil temperature because in commercial production in the field, they are tightly correlated. Given that growth occurs at the meristem which is at the top of corm, so very close to ground level, I would guess that soil temperatures are more important than air temperatures.

There's not really an easy or inexpensive way for someone to effectively raise the temperature of the ground surrounding the corm. A GSHP probably will not raise the temperature high enough to stimulate growth.

Olafhenny
11-29-2012, 03:02 AM
I suspect no one has bothered to figure out the relative effects of air temperature versus soil temperature because in commercial production in the field, they are tightly correlated. Given that growth occurs at the meristem which is at the top of corm, so very close to ground level, I would guess that soil temperatures are more important than air temperatures.

I have no idea, how that applies to tropical plants. But here in the more frigid north, the rule
is simple: Plants grow toward warmth. In fall, when the ground is warmer than the air the
impetus of growth heads down. I.e. the sap retracts from the leaves in the trees and they drop
off. The nutrients from the sap then go into the roots and develop them. That is why the best
time to plant things here is the autumn. It gives the roots time to establish themselves, before
in spring, when the air is again warmer than the soil, new growth bursts upward into greening,
blooms and eventually fruit. Of course there are also seasons in the tropics, but I would surmise,
that they would be more complex and locally diverse, governed by rainy and dry seasons etc.

As a PS to my previous post I would like to add, that I never start wintering my Basjoos, until
after the first frost has damaged the leaves. The much thicker Pseudo stem is then still sound.

Olafhenny
11-29-2012, 03:10 AM
I doubt it has a LOT more to do with daylight hours. I'm sure they are both important -- you need light for photosynthesis, and within reason, more light results in more photosynthesis, and thus more potential growth. But my bananas grow faster in August than in June. There are fewer daylight hours in August than June, but it is warmer in August than June.

Well read my report on the performance of my Ornatas in waning daylight hours and at constant
thermostat controlled temperatures. I am not claiming that to be the definitive answer, but clearly
a strong indicator in this particular case since daylight hours are the only thing that changed, while
the growth slowed.

In the tropics daylight hours are roughly constant 12hrs on - 12hrs off. That state is not even reached until
~Sept 21st.

So the June to August comparison is of doubtful importance

venturabananas
11-29-2012, 02:21 PM
In the tropics daylight hours are roughly constant 12hrs on - 12hrs off. That state is not even reached until
~Sept 21st.

So the June to August comparison is of doubtful importance


Given that I don't live in the tropics (34 degrees north), it is a fact that there are more daylight hours in June than August, yet my bananas consistently grow faster in August than June. The average temperature is warmer in Aug than June. Thus, I conclude that in this situation, temperature differences, not daylight differences are driving growth rate. The response of banana growth rate to temperature is well documented in the literature. That is not to say that day length, or more generally, light exposure is not important, too.

Going Bananas
07-17-2015, 02:17 AM
BUMP....:bananas_b

Resurrecting this thread after 2 years.
Abundance of insight and knowledge
into naner culture.

TY!

venturabananas
07-18-2015, 11:01 AM
There were lots of things discussed in this thread. Which of those do you want an update on?

Going Bananas
07-18-2015, 02:15 PM
I quick read the first time
and found it very mentally stimulating.
Im going to reread and digest it.
For someone new to naner culture,
I thought it was very informative.

Thank You!

Olafhenny
07-18-2015, 10:26 PM
Hi Mark,

given your reply in which you quoted me as writing…:



In the tropics daylight hours are roughly constant 12hrs on - 12hrs off. That state is not even reached until
~Sept 21st.]

So the June to August comparison is of doubtful importance


Your reply:
Given that I don't live in the tropics (34 degrees north), it is a fact that there are more daylight hours in June than August, yet my bananas consistently grow faster in August than June. The average temperature is warmer in Aug than June. Thus, I conclude that in this situation, temperature differences, not daylight differences are driving growth rate. The response of banana growth rate to temperature is well documented in the literature. That is not to say that day length, or more generally, light exposure is not important, too.

…I do not think, that you even have read, what you quoted. So I will express it in a different way: In the tropics, which the bananas call home, the day/night cycle is very close to 12/12. In August you are much closer to that cycle and your bananas feel more like home and closer to conditions, which are anchored deeply in their genetic make-up.
Consequently they feel more comfortable, as far as natural light is concerned, in August through October than they do in June or December. If you could charm up some weather in the ^F 80s and 90s in natural light conditions, you would find similar growth spurts in February thru April.
Best,
Olaf

Richard
07-18-2015, 11:03 PM
... In the tropics, which the bananas call home, the day/night cycle is very close to 12/12. In August you are much closer to that cycle ...
Actually in southern California we have that exposure twice per year during the spring and fall equinox -- near the 3rd weeks of March and September. A huge factor for us that we don't have the sustained humidity of tropical banana ecosystems.

Olafhenny
07-18-2015, 11:58 PM
Richard,

how are your temperatures during February - March? If you live in an arid climate,
that would suggest to me, that the nights would be rather cool then.

Olaf

Richard
07-19-2015, 02:24 PM
Richard, how are your temperatures during February - March? If you live in an arid climate, that would suggest to me, that the nights would be rather cool then.
Not sure why you are mentioning February - March?
The southern CA vernal equinox is in the 3rd week of March, and the autumnal equinox is in the 3rd week of September. At our location the daylight hours are briefly at 12 hours per day. You can explore it further for many latitudes here:
Daylight Hours Explorer (http://astro.unl.edu/classaction/animations/coordsmotion/daylighthoursexplorer.html)
Southern CA is approximately 33.5 deg, and of course the tropics are between -20 deg and +20 deg.

Regarding temperatures during the week of the equinox: Here in the coastal influenced portion of northern San Diego County, some years I have experienced 80 deg daytime weather and others 50 deg at the spring equinox, and likewise 60 deg weather or 90 deg weather at the fall equinox.

http://www.plantsthatproduce.com/imgs/weather-temps-vernal-equinox-2015.jpg

Olafhenny
07-19-2015, 03:36 PM
I was focusing on the the two colder months of the 3 around spring equinox, when
the light is right, but the temperatures may a bit chilly, thus affecting the growth.

Richard
07-19-2015, 04:45 PM
I was focusing on the the two colder months of the 3 around spring equinox, when the light is right, but the temperatures may a bit chilly, thus affecting the growth.
Ok, but as you see from the daylight hours chart, the daylight period here in February is only 10.3 to 11.3 hours, whereas in the Asian banana belt its an hour longer. As for temperatures here -- that's a crap shoot. It was warmer here this February than in many parts of Burma.

venturabananas
07-26-2015, 01:16 AM
I quick read the first time
and found it very mentally stimulating.
Im going to reread and digest it.
For someone new to naner culture,
I thought it was very informative.

Thank You!

I guess the only thing I would add, having watched this particular mat for almost 6 years now, is if you don't "feed" the mat (fertilize, add compost, organic material, whatever) the production will drop off. I'm sure that is obvious; but amazingly, this mat continues to produce fruit, though fewer now than in previous years, without ever being fed (from what my neighbor tells me).

I think my ideal would be 3-4 p-stems per mat, each at different stages, to ensure a regular supply of bananas, without the mat getting out of control. I seem to have a hard time staying on top of the pup removal, so most of my mats have more p-stems than that.

Mark Dragt
07-26-2015, 09:52 AM
It would be interesting to take a soil sample and see what's left of it. Then add fertilizer and note the changes in growth and harvest. I could never have a mat like that.

Going Bananas
07-26-2015, 02:26 PM
I doubt it has a LOT more to do with daylight hours. I'm sure they are both important -- you need light for photosynthesis, and within reason, more light results in more photosynthesis, and thus more potential growth. But my bananas grow faster in August than in June. There are fewer daylight hours in August than June, but it is warmer in August than June.

I agree more with VB and you would really have to look at the whole plant
at the cellular level. The tree doesnt have teeth so it has to move the food and nutrients
from the roots through the trunk(osmosis) to supply the chemical and cellular processes
(that occur in the mitochondria for the ATP and glucose producing cycle)
that builds upward growth of the tree.
In terms of slowing down, I would imagine the decrease in the
respiration/evaporation of water through the leaves and
decrease of sunlight/energy/heat required in the plant ATP cycle.:lurk: