The question of removing the suckers or bottom leaves has been tested and open to debate. The answer is: it depends. In a hot climate the leaves help shade the plant but the leaves also lose water through transpiration. Because you are growing the tomatoes in 12-inch pots, removing the leaves will help balance the smaller root system. To help tomatoes grow in pots make sure the pots drain well. Don't let the soil dry out but do keep it a bit on the dry side. Potted tomatoes also need plenty of nutrients. I use Osmocote on my tomato plants especially those in pots. Keep growing, Marianne Binetti