Growing tomatoes under lights

Chicago Tribune (MCT) - Is starting tomatoes from seed cheaper than buying transplants? Maybe in your second year. Seeds cost little, but it's wise to invest in a light setup to start them.

Tomatoes are light-hungry plants. "If you try to do it in the windowsill you'll get these spindly things that will flop over," says Ronald Wolford, horticulture educator with the University of Illinois Extension in Chicago.

For strong, compact plants, get some fluorescent lights. (Don't use incandescent bulbs, which are too hot.) Ready-made seed-starting units with special grow light tubes start at about $125, for a 24-inch tabletop unit that will accommodate one flat of plants. (One from Gardener's Supply, gardeners.com, is priced at $150.) It's convenient, but the special bulbs aren't essential.

You can invest a little more effort to spend less money. A utilitarian shop fixture with two 24- or 48-inch tubes, one warm-spectrum and one cool, will do the job. Hang it on chains with S-hooks so you raise it link by link to keep the light about 4 inches above the plants as they grow. Get a timer to turn it on and off, and keep the lights on 12 to 18 hours per day, with a break at night.

It can hang from the basement ceiling joists or even from a bar-type coat rack. Gardeners are ingenious: We've seen shop lights hung from homemade wooden frames and even from screw eyes in the underside of a wooden dining table, with the plants sitting on the floor. You only need clearance for the seedlings to get 12 or 18 inches tall by planting time in May.

We've also seen clip lamps and desk lamps with fluorescent bulbs drafted into service, though they can splash an uneven, distant light that may cause stalky plants. Remember the goal: direct, even light that stays close to the top of your plants so they don't stretch.

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