What to do in the garden: Though it has been unseasonably chilly, we should be frost free from now until October. That makes Memorial Day weekend the traditional time for planting frost-sensitive summer vegetables, flowering annuals, and container gardens. Shop in the next two weeks while the selection and quality are best. Watch for garden club plant sales. If critters eat your flowers, buy more impatiens, marigolds, zinnias, and snapdragons. Dahlias, tomatoes, peppers, melons, and other heat lovers could be planted now, but I prefer to wait two more weeks to give the soil time to warm.
Q. Is garlic mustard edible?
A. Garlic mustard can quickly overwhelm woodlands because it blocks the growth of soil fungus necessary for many native plants. But like many wild plants, you can eat it if you know how. Pull the plant out by the roots in May before it finishes producing its four-petaled white flowers, which can be chopped and tossed into salads, along with the jagged leaves. These are less bitter if harvested before the hot weather. Check to see whether you have the right plant by crushing and sniffing the leaves, which should smell like garlic. Bag the roots, which should be eaten only in early spring and late fall and taste like horseradish. You can sauté the leaves on a low heat with garlic and olive oil and then add a few drops of water to steam them for five minutes until they collapse. Add a dash of balsamic vinegar or pine nuts for pesto.
Q. I saw your reply to a question about cabbage moths (“Ask the Gardener: What you should be doing now in your garden,’’ April 10.) I had the same problem. I planted anise hyssop next to the cabbage. The flower attracts pollinators, including wasps that go after the caterpillars. No chemicals. Pretty flowers. Great solution.
A. Just as garlic mustard can change soil chemistry to repress the growth of its neighbors, other plants can enhance the growth of others around them. Many experienced vegetable gardeners use this ancient practice called “companion planting.’’ Some grow herbs like hyssop next to vulnerable plants such as cabbage and cauliflower to repel cabbage moths, as you have. Scientists find the “companion planting’’ concept vague and superstitious, but they have documented many scientific benefits to placing the right two plants together, which they instead call “plant associations’’ and “intercropping.’’ Generations dependent on their vegetable gardens for survival explored plant combinations long before the invention of insecticides, so their fieldwork must be worth something. Experiment in your own garden. The best-known reference book is “Carrots Love Tomatoes’’ by Louise Riotte. Incidentally, Hyssopus officinalis is the Latin name for anise hyssop, an ancient Middle Eastern herb once considered so sacred it was used for cleaning religious sites. It benefits bees and is reputed to repel slugs and promote the growth of grapes. Hyssop produces bushy 2-foot spikes of blue flowers and bitter but edible leaves used in salads, soups, and even fruit pies. It grows easily in partly shady soil sprinkled with lime and can be planted now.