How soon can u give plants nutrients?

Srry if I posted this in the wrong thread.but I have a couple plants about 3 weeks old growing in soil in a little cfl box I have.the soil I'm using isn't the best so I wanted to use some botanicare pure blend pro grow 2-3-5 veg formula that a buddy gave me.but I don't want to introduce it to the plants to early.so on average how old should a plant be before giving it nutrients? And shouldn't veg nutrients have a different npk? Like 30-10-10? Please help me out

hey floppy, average soil's nutrient will last about 3 to 4 weeks...now all you have to wait and see if your plant start turn lime color , really light green or start defs, its time to feed nutrient...myself i will let my seedlings grow into early veg stage i will start to feed...

Ok thanks for your help!

your welcome, dude you said you start with cfl box ? will you transplant it later ?

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