Well that depends on alot of variables. I would use it as directed for mature plants (6" or taller) and 1/2 strength for anything smaller than that. Those fertilizers are organic (GH is Semi-Organic) so you'd have to really over do it to kill your plants. Just start out at a low dose and slowly work up. I would water them 1-2 cups every other day. Just water them until water barely starts to come out the bottom.