Dunno what to say, but when I fill those pots, it takes 4 gallons to do it, and they are twice the size of my two-gallon pots. They also produce plants that are at least double the size of the plants I grew from 2-gallon pots. Add to these facts the fact that when I ordered them, I ordered 4-gallon pots, and that's what it says on the receipt as well, and I am pretty convinced these are 4-gallon pots.

Mathematically speaking they are 10" tall, and 10" square at the top, which is 1000 cubic inches, which comes out to 4.33 gallons. But they aren't quite 10" at the bottom, so they lose a little volume there, and come out to exactly 4 gallons (if they are full). You can use the conversion calculator at http://www.metric-conversions.org/vo...to-gallons.htm to convert cubic inches to gallons if you don't know the math. I measured the pots with a ruler just now, to be sure.

In any case, bzzzzzzt!, you are wrong, they are 4-gallon pots. I also doubt your pots are double the width: that'd be almost 3 square feet PER POT, if they were in fact 20" wide.