It's kinda importaint to know the height an width of these autoflowers if they tell you that in the description from whom you purchased or got them gifted to you. You say 2ft tall but are you in a boxed in bed or just into the ground? I have metal raised beds like metal roof sheets. I'd probley only do 4 every 24" apart. Your gonna have to be really watchful for bugs cause they love weed plants. Best of luck, i don't set mine out till mid June in Oregon. Autos love long days of sun, lots of heat and don't like rain much.