Lettuce grow together

All the rain and cool weather we've had lately is terrible for tomatoes and peppers, which thrive on heat. But it has extended the season for an easy-to-grow garden staple: salad greens. Salad greens like cool, wet weather; they "bolt" -- or go to seed (and in the process become tough and bitter) -- in the arid heat of summer.

A nice thing about lettuce is that you can grow it almost anywhere, anytime. The nutrient demands of these plants are low -- in other words, they don't need really fertile soil, like squash or broccoli. And using them in the kitchen is a no-brainer: Just pick, wash, dress, toss, and eat.

Here's how to grow them: First, pick out a packet of seeds. Burpee sells various packets that contain a variety of complimentary greens. There are tons of types of greens, with names like red deer tongue, black-seeded simpson, and royal oak leaf, buttercrunch, red sails. You can also grow beet greens and arugula (also known as rocket) for your salads.

Some people plant lettuces in tidy rows with proper spacing. This tends to produce nice, evenly formed heads. But I'm lazy. I just scatter seeds in a given area, and I thin as they grow (and I eat the thinnings). My way probably leads to more problems with slugs, which can hide between the packed plants. But I tend to think that thickly planted lettuces will do more to shade the ground they are growing in, keeping it more moist (which is what they like).

Since I plant thickly, I just pull up whole plants, roots and all, to harvest. If you have planted less thickly, you can lop the plant off a few inches off the ground (and it will grow back) or you can peel leaves off the sides.

The plants will bolt when they get too old, too hot, or too dry. You see them shoot up a seed head, almost overnight, and the leaves will be leathery. The leaves will get progressively tougher leading up to this day, so pick them before the bolt happens (unless you want seeds).

Potential problems: Slugs are your main enemy. See our earlier entry on how to deal with them -- handpicking and beer traps are our methods.

Heading into a hot summer: When weather gets hot, you'll have to tear out and plant new lettuce when your old stuff bolts. But you might also consider growing "salad greens" that like hotter weather -- like basil or parsley, for example. Nasturtiums are beautiful flowers -- and they are edible, leaves and flowers both. Mustard also produces highly nutritious greens, but beware urban gardener-farmers: Mustard is also one of the few plants that will absorb lead in the soil. Make sure your soil is clean, and don't grow any food in contaminated soil. (We'll post on that topic sometime in the future.)

If you're really enthusiastic about growing greens, you might consult an excellent new book about the topic: Charles Dowding's Salad Leaves for All Seasons: Organic Growing from Pot to Plot. Dowding, a British gardener, covers just about every green you would want to grow, and various methods for growing them.

If you don't have room to grow greens, you might check out plans for Salad Tables and Salad Boxes from our friends at the University of Maryland's Grow It Eat It campaign. With just a few 2-by-4 planks, some screen and hardware cloth material, and some fasteners, you can make a container that will sit on a deck or patio and grow greens all year long.