If you itch to start growing things weeks before it's time to start most of your seedlings, use the space under lights (or your sunniest south-facing window) to grow quick crops of lettuce.

There is a happy symmetry to the fact that translucent clamshell boxes used to package gourmet salad greens also make ideal containers for growing lettuce indoors. To get the boxes ready for duty, use the tip of a stout knife to make 8 or 9 gashes in the bottom of each one. Then add 2 inches of moist potting soil before planting a pinch (about 25) lettuce seeds, barely covering them with soil. After generously spritzing the surface with water from a pump-spray bottle, pop on the tops and slip the boxes under your grow light, or in any warm, bright spot.

Five days later, when the seeds are up and growing, remove the tops and place them under the boxes, so they become watering trays. The soil usually stays nicely moist if you fill the trays with water every day. By the way, don't try to remove the labels from the lids. Hot water will warp them, especially if they're made from cornstarch.

You can let your boxes of lettuce bask in the sun from a south-facing window on bright days, but they will be happy to spend most of their time under the light. Keep the lights on for about 12 hours a day, like from 7 in the morning until 7 at night.

The first cutting is ready in 3 to 4 weeks. By holding the boxes sideways, you can clip the leaves right into a colander while keeping the growing crowns intact. The plants will be ready to cut again in about 2 weeks.

If you want to use the clamshell boxes to start another crop, you can lift out the mat of seedlings and transplant it to a larger container. As days get warmer in the spring, you can start lettuce and other salad greens in clamshell boxes and transplant the mats into a cold frame or plastic-covered tunnel. 

Have you tried similar tricks at your house to grow good things to eat indoors in late winter? Please share your stories in the comments section below.

A few weeks ago, Mother Earth's intrepid editor-in-chief, Cheryl Long, told me about a study from Kansas State University in which good quality organic lettuce was successfully grown in high tunnels in July and August with the use of 40 percent shade. That intriguing tidbit coincided with visits to two local organic farms — Five Penny and Full Circle — that use high tunnels. It's hot in those things! Surely if lettuce would grow in a high tunnel in Kansas in August, I could work a similar wonder in my Virginia garden. 

I began by starting seeds indoors, because lettuce germinates poorly (if at all) in hot soil. After the little plants gradually became accustomed to strong sun, I set them out under a shade cover made from a double thickness of black nylon net (75 cents at the fabric store) attached to wire hoops with clothespins. The cover provides about 30 percent shade, and the lettuce is doing great!

On very hot, sunny days, I add a lightweight piece of cotton sheeting to block even more sun, and the lettuce doesn't mind one bit. In Hawaii, summer lettuce is routinely grown under 35 percent to 50 percent shade.

How does it taste? The Kansas State study included customer surveys, and there were no complaints about the flavor. As for my experiment, I'm already calling it a success because I have garden-fresh lettuce for one of the season's most perfect foods — tomato sandwiches.