Answer: Because indoor lights aren't nearly as bright as sunlight, the guideline is to keep the lights 4-6 inches from the top of the plants, adjusting that as they grow. In other words, maintain the same distance as the plants grow, moving the lights up as necessary. You didn't mention how long you leave the lights on. They should be on 16 hours a day and turned off at night. Putting them on a timer is helpful to maintain a schedule. Heat pads are good to help germination, but once the seedlings are up and growing you can turn it off.
If you start your seedlings in a sterile soilless mix, they will need to be very lightly fertilized to provide nutrients. Start fertilizing after they have developed a set of true leaves. Use a diluted formula about once a week. After they are transplanted to a real soil mixture, increase the time between fertilizing to about two weeks.
Seedlings won?t thrive if crowded, as they require both air circulation and light. When thinning crowded seedlings, snip the extras with scissors at the base of the plant rather than yanking them out. This helps prevent disturbance to developing root systems. I hope this info helps!
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