Q&A: Are Grow Lights Necessary?

I grew a small vegetable garden last year with reasonable success. This year I want to start my plants indoors, to get a jump-start on the season. Do I really need grow lights or is the light from a western window sufficient?—MS, Smithfield, R.I.

Answer: The light from your western window is not sufficient, assuming you intend to grow them inside for several weeks. Your seedlings are likely to stretch toward the light, resulting in leggy, weak plants. You can meet their needs simply with a tabletop fluorescent lamp. The bulb should be just a couple of inches above the seedlings. (You’ll need to adjust its height as the seedlings grow.) Leave the lights on for 14 to 18 hours a day. A timer will make this easy for you.

If you intend to start a few plants each year and keep them inside for just a couple weeks, this is all you really need to do. Should you get more ambitious, it’s not difficult to make a couple of shelves with shop lights hung on adjustable chains (again, so that you may keep the bulbs close to the growing seedlings). Full-spectrum bulbs, or plant lights, are only a few dollars more than fluorescent bulbs and can result in stockier plants. Proximity and duration are still critical.

Be sure to harden off your plants before thrusting them into the garden after the last frost date. A fan can be used to begin this process, gently at first and for short periods. Stop if you see signs of wilting. You can also carry the plants outdoors for a few hours at a time on pleasant days until they are accustomed to breeze and sun.