lower numbers are good if your not experienced with adding nutes. High concentrations can easily destroy your plant or stunt it badly. Thats why if your new at it (like I am), its better to use lower concentrations until you get the feel for what your plant is asking for.ohhh,It may be time released,I will check in the morning.I saw quite a bit of tomatoe fert but was all high in nitrogen.I read that lower numbers all together could be better...2-7-7 rather than like 10-20-20 or something,dont know just lack of option and low nitrogen,seemed good.