Indoor Vegetable Gardening
By John Jett, WVU Extension Service horticulture specialist
If you want fresh, homegrown vegetables over the winter, or if you don’t have an outdoor space in which to place containers, try indoor container gardening. Of course, you cannot have a full garden in the house, but a bright, sunny window can be the site for growing fresh food all year. Some small-fruited tomatoes and peppers, several types of lettuce, radishes, and many herbs are among the plants you can include in an indoor garden.
Watering and fertilizing
Follow directions given above for preparing pots, watering, fertilizing, etc . However, plants will dry out less quickly indoors and will grow more slowly so they will need less fertilizer. To make watering easy, set the pots in large trays with an inch or two of decorative stones in them. Not only will this prevent having to move the plants to water them, but it will also provide humidity, which is a major requirement, especially during winter when the house is warm and dry.
As mentioned before, a sunny window, preferably south-facing, is almost a must for indoor vegetable growing. Fruiting vegetables, such as tomatoes and peppers, will also need supplemental light, such as a combination warm white/cool white fluorescent fixture, during winter months. Insufficient light will result in tall, spindly plants and failure to flower and set fruit.
What to plant?
Herbs are a first choice for many indoor gardeners. Many are less demanding than vegetable plants, and cooks find it pleasant to be able to snip off a few sprigs of fresh parsley or chop some chives from the windowsill herb garden. Chives grow like small onions with leaves about 6 inches tall. These plants prefer cool conditions with good light but will grow quite well on a windowsill in the kitchen. One or two pots of chives will provide leaves for seasoning salads and soups. Plant seeds or small bulbs in a 6-inch pot. The plants should be about 1 inch apart over the entire surface area. Wait about 12 weeks before cutting the leaves. For variety, try garlic or Chinese chives, which grow in a similar fashion but have a mild garlic flavor.
Parsley seeds can be planted directly into 6-inch pots, or young healthy plants can be transplanted from the garden. One vigorous plant per pot is enough. Standard parsley develops attractive, green, curly leaves about 6 or 8 inches tall. Italian or single-leaved parsley has a slightly stronger flavor and is a favorite for pasta dishes. Leaves can be clipped about 10 to 12 weeks after seeds are planted.
Cilantro or the leaves of the young coriander plant can be grown in the windowsill garden. Cilantro is used in Oriental and Mexican dishes, but it is not available in most grocery stores and must be used fresh. Grow cilantro as you would parsley. Thyme and other herbs will also grow well indoors if given the right conditions.
Tomatoes: The small-fruited varieties of tomatoes, such as Tiny Tim and Small Fry, and the paste tomato, Roma, may be raised quite satisfactorily in the home. They will challenge your gardening ability and will supply fruits that can be eaten whole, cooked, or served with salad. The Tiny Tim tomato grows to a height of about 12 to 15 inches. Small Fry, which is about 3 feet tall, and Roma will need more space and should be located on an enclosed porch or in a sunroom. Several varieties have been developed for hanging baskets, too, which may be worth experimenting with.
Peppers: Some of the small-fruited peppers may be grown as houseplants. Like tomatoes, they prefer warm, bright conditions to grow well indoors. Fruits of peppers and tomatoes will be ready to harvest about 10 weeks after planting. Whiteflies and aphids may present a problem on indoor tomato and pepper plants. Keep a close watch for these pests so that they do not get a good start in your planting. Yellow sticky traps, either purchased or homemade, are effective in trapping whiteflies. Insecticidal soap or other pesticide approved for vegetable plants can be used to control aphids. Fortunately, you will be less likely to experience problems with such outdoor pests as tomato hornworms, corn earworm (in peppers), and late blight than you would if plants were outside.
Radishes: For a quick-growing crop, try radishes. These must be grown very rapidly if they are to be crisp and succulent. Scatter radish seeds on moist soil in a 6- or 8-inch pot. Cover with ¼ inch of soil and place a piece of glass or plastic wrap over the pot to conserve moisture until the seeds germinate. Carrots are slower, but they can be grown in the same way; use the small-rooted varieties such as Little Finger for best results indoors.
Lettuce: Experiment with various types of lettuce. Leaf lettuce and the miniature Tom Thumb butterhead are good to try. Space them according to package directions. Keep lettuce moist and put it in a very sunny spot.
Sprouted Seeds: If light is limited, an old standby for fresh taste and high food value is sprouted seeds. Almost any seeds can be sprouted: corn, barley, alfalfa, lentils, soybeans, rye, peas, radish, mung beans, sunflowers, etc. Use only special seeds for sprouting available from health food or grocery stores to avoid the possibility of getting seeds treated with pesticides. Use any wide-mouthed container such as a Mason or mayonnaise jar. Soak seeds overnight, drain, and place in the container. Cover with a double cheesecloth layer held with rubber bands or a sprouting lid. Set the container in a consistently warm spot; rinse and drain seeds two or three times daily. In three to five days, sprouts will be 1 to 3 inches long and ready for harvesting.
⊕Consult seed catalogs for varieties adapted to container culture.
⊕⊕FS = Full sun; FS/PS = Full sun; tolerates partial shade; PS = Partial shade