I was looking through my books for another post and ran across some information I had forgotten all about.
The book is All About Tomatoes (1981).
The author (Walter L. Doty) completed the following tests:
HOW MUCH SOIL?
compared containers holding 4 cubic feet, 2 cubic feet, and 1/2 cubic feet (all were watered and fertilized the same//Better Boys)
here are the results:
4 cu. feet height 66" 58 tomatoes
2 cu. feet height 56" 48 tomatoes
1/2 cu. feet height 46" 12 tomatoes
Yield alone is won by the biggest container BUT if you compare maximum production from the mininum amount of soil the 1/2 cu. feet size would win as the 4 cubic feet container holds enough soil to fill eight 5 gallon containers. 8 times 12 == 96 (double that of the 4 cu.feet)
((I have never liked using 5 gallon containers and have not gotten the same results --maybe I don't fertilize enough. Even when folks post pictures of their plants in 5 gallon containers they don't aways look that great to me--they look like mine-kinda of skimpy.) . I have settled on 15 gallon for the bulk of my containers and I'm happy with that size though I prefer my even bigger containers. But I may try a 5 gallon again and fertilize the heck out of it but how will that effect the taste of the fruit?))
2nd experiment:
Compared planting in top soil vs synthetic soil.
THe results: Synthetic soil mix produced twice as much. ((we all know that one
)) Top soil did fruit and ripen earlier though.
3rd experiment-this is a weird one. I will just give the results. "In all test of production in 5-gallon containers, the number of fruit is greater when the vine is trained in a FAN SHAPE on a trellis."
Well, happy container growing!