Thanks for the Bimbo Report. LOL
If you google square foot gardening, it might help with your question regarding number of plants. IIRC Bush Beans are 9 per sq. foot. Regular Tomatoes 1 per sq. foot. Carrots are 16 per sq. foot. Melons are 1 per 2 sq. foot. Cukes are 2 per sq. foot. Spinach is 9 per sq. foot. Leaf lettuce is 4 per sq. foot.
I would think that plants with shallow roots, would not need a five gallon bucket’s depth, even though they might need the width/surface area. I easily grow spinach and lettuce for example in about 4 to 6 inches deep pots.
Thanks so much for the square foot info. about certain plants. Bush beans 9 per sq foot is amazing, would not have thought that many in that amount of space. I have copied what you wrote to save that about the beans and the others. That really helps.