Debabrata Ghosh wrote:


Here is a little formula that works for me.
Measure the diameter of both the top and the bottom; let's say they
are D1 and D2 (in inches). Then, r1, r2 are radii (again in inches).
Measure the height of the pot, let's say it's x inches.
Define, h1 = x * r1 / (r1 - r2)
h2 = x * r2 / (r1 - r2)
Then, the volume of the pot in cubic inches is (volume of a cone):
(1/3) * pi * (r1 * r1 * h1 - r2 * r2 * h2)
Divide this by 1728 to get the volume in cubic feet (by about 230.67
to get it in gallons).
This over-estimates a bit if the pots are curved inwards, and, as
Cass said, you'd need to fill less in any case.

Very impressive! Honestly, I am in awe of engineering and and other
scientist types. I sit back and observe as though I am on some sort of
Cultural Anthropology internship. Such precision and attention to detail
and accuracy takes my breath away--really!

Now then: here is a little formula that works for me:

Go to the garden shop. Find the potting soil you want. Eyeball the bags
and think, hmmm, one bag or two? Decide "oh, hell, it doesn't matter. It's
not like I'm not going to be able to use the leftover soil." Buy two bags
for each pot.










I agree with Bob, 19-21" ones aren't big enough. I am moving over my
favorite ones to 24" pots.

Bob, any idea where I can buy 30" pots?

Thanks,
Debu.