markhillis

Ok, so I've got a couple of banana plants that started out great. My drains ok but not super fast, so when trouble started I thought I was overwatering, even though it is summer in Phoenix and I had read that it's almost impossible to overwater when the temps are 105 and above. So I backed off and started watering less....that seemed to help a little. Before that the cigar-roll leaves would emerge with black spots in sections. After I cut back on water the leaves come out huge and beautiful but as soon as they completely unfurl (or almost unfurl) they start getting these brown dead areas...in one day. I have posted several photos of the biggest plant and one photo of the smaller one, which isn't as bad. They get regular fertilizer, compost, leaf clippings, etc.
I don't think they're burning... It was only 100 today when this big leaf opened light green and then developed these bad areas within a few hours. Other leaves have not suffered due to the heat other than wilting everyday.

edwmax

Looks like sunburn to me. The plants need afternoon shading. Also the white metal wall is reflecting intense sunlight too.



My plants get afternoon shading and water misting to cool the leaves and the ground under them. Temps here are in the upper 80's & low 90's. ... But, Direct sunlight could easily push the surface temps on the leaves over 100.

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sputinc7

Also, stress that happened 2 weeks ago can manifest today. Maybe that is it...

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If you lose your head and give up, you neither live nor win.

https://sputinc7.wixsite.com/covwc

Varieties I supposedly bought: Manzano, Cavendish, Blue Java, Sweetheart, and Gros Michel.
What it seems I actually have: Brazilian, Cavendish, Namwah, Dwarf Red, Gros Michel, Pisang Ceylon, Veinte Cohol and SH 3640, and American Goldfinger. FHIA 1, Paggi and FHIA 17... Always room for one more.

markhillis

Thanks for the input. I'll keep working with them and see.
I just didn't want to have some kind of disease or insect problem manifesting.

markhillis

So my saga continues. I'm afraid I'm losing my largest plant...the ice cream banana. So you can see the earlier photos of this plant and another one. I shaded the plant and have tried not to overwater. But I'm wondering if my overwatering in the past caused a rotten place that's destroying the stem...?
Otherwise, what is the cause of this large black area on the stem? The first photo is the large ice cream. The second one is my goldfinger, which has done fairly well....is this a similar black area forming?....I'm so frustrated.

edwmax

That wasn't visible in the first pics. .... Cut the pstem off just below the black spot. Look the see if the lower center is white. ... Then I would cut the black section open to what was going on. ... May be you can save the corm.

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markhillis

I didn't explain well. No, it wasn't in the first pics because it wasn't there. The issue then was the leaves. Only after a couple of outer leaves fell away did the black show up. What does it mean if it is white in the center...good?

Akula

A white center is healthy. Brown color is rot.

A raised bed of about 1' above the surrounding soil would help to minimize risk of over watering. A raised bed will allow some roots to get above any trapped water due to soil conditions (compacted or minimal draining soil). Mulch to minimize evaporation losses.

edwmax

Several things might be the cause, but none are good; injury to the pstem; bug bored into the pstem; fungus infection/rot. So it is hard to tell for now. If everything is good below the cut, a new green leaf should show in a few days. ... I think may be you got a choke for some reason.

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