Seedlings starting

Once I put seeds in soil solo cups when do I need to start introducing nutrients. Also what do y’all recommend to prevent against pm and bugs.

Depending on soil (happy frog for example) can take a month or longer to strip nute. And bee-safe 3 n 1 works,cant recall the name of the other stuff i got,its in a green spray bottle but works killer good. Good venting and proper air flow can help aganst pm. Ive learned the hard way so i will help where i can.

on auto’s, if using any organic soil, I do not add nutes till they begin to flower, anywhere fro 4 to 5 weeks
On photos, learn to read your plants. Let soil and water do ts job, learn to recognize when they are telling you they are hungry