After like a inch or two more growth you may want to go ahead and transplant them into a 3 gallon or whatever your preference But nice little vegs there. Probably may want to add some Bat guano to the soil if you don't have any. Is your soil premixed? Store bought? timed? Basically I am asking does your soil contain nutrients. If not you may want to invest in a nute that has some nitrogen to give your plants color and better life. Good luck APZ