How to Start Vegetable Seeds With Lights


Starting vegetable seeds indoors allows you to get a start on the gardening season in late winter or early spring. But it's hard to provide indoor seedlings with enough lighting. Windows rarely provide enough light, and they are often cold and drafty. Starting the seedlings under fluorescent lights ensures the vegetables receive enough light for a healthy start. There is no need to purchase expensive grow light systems; regular fluorescent fixtures, such as shop lights, are sufficient.

Step 1

Fill a seed starting flat with a sterile potting mixture. Use a soilless mix or another mix that is formulated for seed starting.

Step 2

Water the potting mixture in the flats so it is evenly moist throughout but not overly soggy. Allow the flat to sit for a few hours or overnight prior to planting so the potting mix has a chance to absorb the moisture properly.

Step 3

Sow the vegetable seeds to the depth recommended on the back of the seed packet, generally twice as deep as the seed's width. Leave a 2-inch space between the seeds in the flat in all directions.

Step 4

Cover the top of the flat with plastic wrap or slide it into a plastic bag. Set it in a warm (65- to 85-degree-F) room until the seeds germinate, which takes seven to 21 days depending on the vegetable variety.

Step 5

Set up your grow light system while waiting for germination. Place one cool-white and one warm-white fluorescent tube in a dual-tube light fixture. Plug the light fixture into a timer, available at hardware stores, prior to use.

Step 6

Remove the plastic wrap once seeds germinate. Move the seedling tray under the fluorescent lights, elevating the tray so the tops of the seedlings are 2 to 4 inches from the light tubes. Set the seed flat on top of boxes to elevate it to the proper distance.

Step 7

Water the soil as necessary to keep it moist, and lower the seedling tray as the plants grow to maintain the 2- to 4-inch distance. Set the timer so the lights remain on for 16 to 18 hours a day. Generally, vegetables require twice as much artificial light as they do natural sunlight.

Tips and Warnings

  • Don't set up your seedling area in a place near air vents or drafts. Overly cool or warm air can kill or weaken the seedlings.

Things You'll Need

  • Seed flat
  • Potting mix
  • Seeds
  • Plastic wrap
  • Light fixture
  • Fluorescent tubes
  • Timer
  • Boxes


  • Utah State University: Starting Vegetable Seed Indoors
Keywords: planting vegetable seeds, seed starting, growing under lights

About this Author

Jenny Harrington has been a freelance writer since 2006. Her published articles have appeared in various print and online publications, including the "Dollar Stretcher." Previously, she owned her own business, selling handmade items online, wholesale and at crafts fairs. Harrington's specialties include small business information, crafting, decorating and gardening.