This is always one thing that makes me nervous in the growing process – repotting your new seedlings. Sherxr from Ur Resident Chef had a question about when and how to repot. Well, I’ve had my share of successes and failures in this regard, but I’ll share with you the process that seems to work best.
I’d wait until they have one set of true leaves before you move them to a pot (unless they are too crowded). As the seedlings grow make sure they have some airflow to help stave off dampening off fungus and also to make the stalk strong before you repot them. If you plan on setting the pots outside – like on your porch or a rooftop garden – harden them off before you repot unless they are overly crowded.
Hardening off is a process where the plants get accustomed to the conditions outdoors – gradually. Take them outside early in the morning for an hour or two so they get used to the air flow and sunshine. Increase the time they spend outdoors gradually as the days go by. At first keep them out of the heat of the midday sun or you’ll end up with dead seedlings fairly quickly. As When you are getting ready to repot let them dry out a bit and stop fertilizing. Get your pots ready with a good potting mix and use the first leaves that came up after germination to pull them from their current location. A pencil usually works well to lift the roots from the dirt.
For tomato and pepper seedlings if they have more than one set of leaves you can probably bury the plant up to the lowest set in the ground. This gives the plant added stability as it grows.