New clone feeding?

Heyguys. I just got 5 clones, sadly don't know the strain but it's indica heavy the leaves are pretty broad.

Theyre in red solo cups, and they have obvious node growth since they were just stalks, when should I feed them? I have some 20-20-20 I picked up last night that u mix with water, it's a general fertilizer for veggies and herbs, and then when it flowers I'm going to get a different kind of the same brand, it's a bloom formula used the same way but it's like 8-36-10 or something.

Anyway, when should I start feeding them? This stuff is really concentrated so I will deff use like half or a third strength for the first feeding whenever that is

Take it easy on the nutes 20% to 25% for a first feed,it's easy to over do it.The soil in the cup should supply nutes for three or four weeks,make sure the clones aren't root bound and transplant when needed.If you live where it is hot make sure the soil in your pot is buffered from direct sun.When i have the plant in a nice amount of soil and the color fades a bit i start to fertilize slowly making sure not to over or under water.