Call It Guilt-Free Darwinism

Gardeners are good at nurturing, but it is a quality that some have in excess. Such a friend recently confided how much she minds the job of thinning, not because it's tedious (though by the end of a long carrot row, it is) but because she hates to kill any seedlings she has sown. Crowded, struggling, choking, it doesn't matter. They are all her babies.

Recently she had a breakthrough while thinning late-planted lettuces. By holding her finger at the base of the one she was saving while she yanked a few of its neighbors, she was able to focus on protecting the survivor instead of mourning the castoffs. The finger trick lessens that tug on the roots of the plant left standing, and it helped my friend to see thinning as a positive act. Just as with pruning (another tough-love garden skill), she was giving her plants a better chance to be productive by removing competition from their beds.

Plants sown too thickly become weeds to one another if not managed. So you must keep motherly love out of your mind and Darwin at your elbow. Pick the strongest plants, and protect them against less-promising neighbors. To form good heads, lettuce needs a good 10 to 12 inches of breathing room in the row -- that is, unless you're sowing a mix of baby greens meant to stay crowded and small for repeated cut-and-come-again harvests.

The same goes for fruiting plants. My husband has a firm hand with his beefsteak tomatoes early in the season, thinning the tiny fruits to four or five per cluster. That way the plant will spread out its efforts over the whole stem and bear productively over a longer period. Similarly, if you have a peach tree that you have not thinned, there is still time to remove the smallest fruits, leaving an average width of about two fists between the ones you are saving. They will be bigger at harvest time and will put less stress on the tree. Peach boughs are brittle and prone to breaking in summer thunderstorms, especially when weighed down. By removing some of her progeny, you are saving a mother tree.

In July, you can start sowing greens for fall in the spaces where early crops such as peas and radishes have grown. Swiss chard, spinach, Tuscan kale and beet greens are good choices. Thin them rigorously if your goal is large, mature plants, but leave them just an inch or two apart for baby salad crops.

Using a sharp knife or scissors to thin plants is another good way to reduce stress on the roots of the ones left to grow. If that still seems wasteful, wash the discards and turn them into a thinnings salad, a dish just as succulent in midsummer as it is in spring.