Indoor herb gardens need tender care

Q: I want to keep herbs on my windowsill, but I don't know where to begin. Do you have any suggestions?

A: Attractive, aromatic and delicious, herbs are a practical favorite of gardeners everywhere.

Not every herb is suitable for growing indoors, however: Dill, cilantro and common garden cress do not regrow after they're cut, and therefore probably don't warrant the effort indoor cultivation requires. Good herbs for this type of environment include spearmint, sweet basil, Greek oregano and chives.

Raise herbs from seed in well-drained potting soil high in organic matter (two parts potting soil mixed with one part sand is ideal for most herbs). Although any container with adequate drainage is appropriate for your kitchen sill, clay pots are especially effective, as they are porous enough to let moisture and air pass through.

Herbs do best with at least four hours of direct sunlight each day from a south- or east-facing window. Even this might not be enough: Supplementary lighting may be required to supply the intensity and duration of light equivalent to the outdoor summer daylight in which the plants thrive. Grow-light units, available at garden centers and nurseries, can provide this necessary additional light.

Herbs tend to need less frequent watering than most houseplants. Soil should be dry to the touch before it is watered.

When you do water, though, make sure the soil is thoroughly saturated, all the way to the drainage holes in the bottom of the pot.

As for temperature, indoor herbs need cool air — no higher than 70 degrees during the day, 10 degrees lower at night — and proper circulation.

Place a small oscillating fan near your pots to keep the air moving, which will prevent fungus growth and insect infestations.

Q: What is the best way to clean window screens?

A: One of the best parts of spring cleaning is throwing open the windows to air out the house. Unless you want dust and dirt blowing in, though, you'll need to clean your window screens first. Dirty window screens block light and make your windows look filthy even when the glass is sparkling clean.

If you remove screens for the winter, clean them well before installing them again for the season.

If you leave them up year-round, they should still come down once a year for cleaning.

When removing screens, keep track of any hardware — stash screws or other pieces in a plastic bag (or several plastic bags if you have different kinds of windows and screens in the house), and add labels so you'll know where everything belongs later.

To clean the screens, lay them flat on the ground or lean them up against a wall. Using warm water and a mild detergent, go over each screen with a scrub brush, washing the mesh as well as the frame. Then rinse the screens thoroughly with a garden hose, and allow them to dry in the breeze and sunlight.

Between major cleanings, you can keep your screens clean by wiping them down with a soft brush, and whisk away any loosened dust and dirt with a hand-held vacuum attachment.

Questions may be sent to mslletters@marthastewart.com or Ask Martha, care of Letters Department, Martha Stewart Living, 11 W. 42nd Street, New York, N.Y. 10036. Sorry, no personal replies.