How can I keep my seedlings from becoming "leggy"? They shoot up, and even when the true leaves appear, there is much more stem than I would like. What are the secrets to getting plants similar to those I see at the local greenhouses?
You might be interested in the seed-starting tips at:
Proper, even light is one key to preventing leggy seedlings. Weak light, or not enough hours of light, can cause legginess. There are lighting kits you can buy for seed starting, or you can make your own. One option is to hang 1 cool-white fluorescent light and 1 warm-white flourescent light (or 2 full-spectrum fluorescents) about 2 to 4 inches above the seedlings; the distance is important--too high, and the seedlings will stretch to the light and become leggy. You can also place seedlings near a window, but make sure there is enough light for them--a south-facing window is best. Provide at least 12 to 16 hours of light per day, whether by a window or under a fluorescent.
Other causes of legginess can be nutrient-related. Too much nitrogen, for example, will cause legginess.
Also, it helps seedlings to produce sturdy stems if you very gently brush the tops of the seedlings every so often.
I was looking for the same answer. I thought there was enough light from my window, but no.
Next year I will have a grow or shop light so that I can raise and lower it as needed. For now I added in a lamp and have the ceiling light on too. I also positioned a few mirrors to hopefully reflect more light.