Mel Bartholomew, creator of the Square Foot Garden.) Both piles were picked the same day. The one on the left has 10 tomatoes, while the one on the right has 9.
On the left are the tomatoes I picked from my neighbor's traditional backyard garden while they are out of town. On the right are those I picked from one of the square foot gardens in our backyard. Both are sun-ripened, yummy garden tomatoes. But ours, as you can see, sometimes even split from growing so large.
I know there are other factors to consider, such as soil and amount of sun and water received regularly, but I feel that my trimming of the plants has really increased the growth of my tomatoes this year.
I had never heard of trimming tomato plants until the first time I read Mel's book, All New Square Foot Gardening, several years ago.
I understood the concept but wasn't convinced of its effectiveness. On page 159, Mel writes: "The theory behind pruning to one single stem is that all the energy goes straight up the main stalk, and you will have more tomatoes per square foot than if you allow it to put energy into branching out." Makes sense, doesn't it?
The first time I did this (a few years ago), I religiously trimmed the "branches" once a week. I don't remember if our tomatoes were bigger than usual that year, but it did seem like the tomatoes were being a little overwhelmed by our Arizona sun (even in the cooler mountains, where I lived). And when I explained Mel's method to my mom, who lives in the southernmost part of Utah, where the summer sun and heat get extreme, she was doubtful that this method would work there, for the same reason. Those tomatoes needed their branches to shade and protect them, she thought.
So this year, in northeastern Utah, I put those two trains of thought together and it has worked beautifully. I don't get around to trimming branches every week, and I leave many of them on for shading and stability, but I've found that trimming out extraneous limbs gives space for air and sunlight to get down into the plants and ripen the tomatoes. And we've never grown tomatoes this big!