I bought this plant food but it says 2 scoops per 2.5L of water. How much should i put in a spray can that is 800ml and do i spray it on the leaves or in the soil...?
If you're going to use a foliar spray use about 1/10th strength as to powdered plant food that you mix with water, leave that to the rose growers, go to a hydro store and get some general nutrients or advanced nutrients to mix in your water at 1/10th recommended strength...
I personally prefer SUPERBAT guanos for my watering, all natural (stinks like a bastard) and it makes for some tremendous growth, comes in all mixes for vegging, flowering etc......