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Patty in Wisc
11-14-2008, 04:19 PM
I have a big round tree pot that is about 24 inches wide at top & 17 1/2 inches high. It is tapered very slightly at bottom. What gallon size pot is this? A friend bought a tree in it & gave me the pot.
I'm good at math but forgot how to figure this.
And, why are 5 gal plant pots so much smaller than a 5 liquid gal bucket? Thanks

lorax
11-14-2008, 05:21 PM
Well, for a cylinder, volume=(pi)(radius squared)(height)

SO:

3.14159 x 144 square inches x 17.5 inches = 7,916.8068 cubic inches

1728 cubic inches in 1 cubic foot, so that's 4.58 cubic feet

and 4.58 cubic feet is 34.26 gallons.

So it was probably sold as a 35 gallon pot.


Now to the point of a 5-gal plant pot vs. a 5-gal bucket. The bucket is measured in US Gallons and the pot is in Imperial Gallons. This makes the bucket some 1.2 times bigger. (Don't ask me why those two aren't the same; I'm from a metric country) Small wonder that most of the rest of the world prefers SI (metric) measurements. Because a 1L plant pot is the same volume as a 1L bucket for me.

john_ny
11-14-2008, 05:46 PM
Most container sizes are "trade sizes", in other words, what they are commonly referred to in the trade. Most are actually considerably smaller than their "trade" size.
To find the actual capacity of your container: Use the formula, pi x radius squared X height. You would want to take the average diameter. If the top is 24", and the bottom is 22", the average is 23". Since you need the radius, you take ½ of that, or 11.5", and square it (multiply it by itself) giving you 132.25. Multiply this by pi (3.1416). This will give you the average area, 415 square inches. Multiply this by the height, 17.5". This will give you the volume, in cubic inches, 7271. Divide this by 269. (There are approx 269 cu. inches in a gallon) the result is the capacity of your container in gallons. (Approx. 27 gal.)

Patty in Wisc
11-14-2008, 07:16 PM
Thanks Lorax & John. I should round it off as a 30 gallon? LOL
Lorax, Imperial gal is more than US gal. I bought a 5 gal bucket of something from Canada (Imperial gallons) & it is a US 6 gal bucket. If the 5 gal pot is imperial gal, it would hold 6 gallons. 6 gallons = 5 Imperial gallons. I bought 5 gal plants & the pots don't look close to being 5 US gallons.

chong
11-14-2008, 08:49 PM
.............................................................
So it was probably sold as a 35 gallon pot.


Now to the point of a 5-gal plant pot vs. a 5-gal bucket. The bucket is measured in US Gallons and the pot is in Imperial Gallons. This makes the bucket some 1.2 times bigger. (Don't ask me why those two aren't the same; I'm from a metric country) Small wonder that most of the rest of the world prefers SI (metric) measurements. Because a 1L plant pot is the same volume as a 1L bucket for me.

In the US, a 5 gallon bucket will hold 5 gallons of liquid. This is required by commerce. A 5 gallon pot may hold between 4 to 6 gallons of soil. In the case of the bucket, the accuracy of the contents is important because the content is what is being sold. While for pots, it is the pot that is being sold, and typically, one does not fill the pot to the brim as you would a bucket. So, it all depends on the manufacturer on how much he wants to "chinse" on materials.

Also, an Imperial gallon is larger than US gallon. So, if as you claim that the pot is in Imperial gallon, an equivalent bucket will be 1.2 US gallon. Patty is wondering why the gallon pot is smaller, not bigger, than the gallon bucket.

Bottom line is that both are supposed to be technically the same. There are governmental controls on the accuracy of amount of the contents in a bucket, while there are none for pots.