Does this planting density look good to you

[gtnate]

I have 4 containers for growing tomatoes. My largest containers are, I believe, about 15 gallons. Last year, I planted a single tomato plant in each container (see picture), and I think that it worked really well.

With that said, I'm really thinking of changing things up this year and planting 2 plants in some of the bigger containers and then pruning them to only 2 main stems. My main motivation for doing this is that I would like to grow more varieties.

What do you guys think? Would two plants overcrowd these containers? Should I stick with the 1 plant per container rule and be happy knowing that what I am doing will provide good fruit?