How to Prevent Leggy Seedlings

Bright light prevents leggy seedlings.

Growing plants indoors from seed can be challenging for a novice gardener, with leggy seedlings a potential problem. These occur when seeds sprout and develop long thin stems that flop over. The critical time for preventing leggy seedlings occurs right after the seeds sprout. At this point, you need to provide them with intense light.

Things You'll Need

• Grow light
• Bulbs
• Chain or rope to suspend the grow light

Instructions

1. Place the seed tray on a heating pad until the seeds germinate; remove the pad once most of the seedlings appear.

2. Keep the soil moist so that the seeds have the ideal environment for germination. Place plastic wrap over the seed tray with holes poked in it so the soil can remain moist yet breathe.

3. Hang a grow light or fluorescent lighting 2 to 4 inches above the sprouting seedlings so that they don’t grow too quickly toward a more distant light source. Set up a grow light that does not produce much heat to avoid drying up the seedlings and potentially burning them. If you use fluorescent lighting, pick bulbs that say "cool white" for example or "day light" and supplement them with one standard fluorescent light in the same fixture. This gives the plant the full spectrum of light to provide an adequate growth environment.

4. Raise the lights so they stay 2 to 4 inches above the tops of the growing seedlings to keep them compact and strong for their transfer outdoors. Adjust the chain or rope suspending the lights up toward the support stand.

Tips & Warnings

• Keep the grow light or fluorescent lighting 2 - 4 inches above the tops of the seedlings for the most intense light, and best growing conditions.

• Be careful not to use grow lights that produce intense heat. These lights will burn or dry up your seedlings due to how close the lights need to be for sprouting plants.

References

• Iowa State University Extension; Successful Seed Germination; Sherry Rindels; 1996