Best fertilizer for my plants?

Hey guys, my plants are about 3 weeks old, what fertilizer would you reccomend i give them? Not the names, but what nutrients are good for the plants? i'm already making compost, and it seems to be decomposing nicely, i'm gonna throw that on in a few weeks, but yeah... any ideas?

Vegging plants love Nitrogen

seeds,clones ,flowering phosphorus.......young plants do good with phosphorus i feed my clones this .i spray them in the dome and soak my cubes in weak stregth..once clones have roots i stil use until about 5-10 days then i water with plain water a few days and move on to nitrogen