SOIL: Well-drained, loam.
TEMPERATURE: Warm (70° to 80°F).
MOISTURE: Moist, but not waterlogged.
PLANTING: Transplant after all danger of frost is past and when the soil has warmed.
SPACING: 18 to 36 inches by 36 inches if staked or caged.
HARDINESS: Tender annual.
FERTILIZER NEEDS: Heavy feeder. Use starter solution for transplants. Sidedress one to two weeks after the first hand or cluster of tomatoes begin to develop with 3 tablespoons 33-0-0 per 10-foot row. Sidedress again two weeks after the first ripe tomato with a balanced fertilizer such as 5-10-5; repeat one month later.
Tomatoes are valuable garden plants in that they require relatively little space for large production. Each standard tomato plant, properly cared for, yields 10 to 15 pounds or more of fruit.
Choose varieties with disease resistance bred in for best results. Letters after the variety name indicate tolerance or resistance to the following:
Fusarium Wilts Race 1(F)
Early Blight (As)
Fusarium Wilt Race 1 and Race 2 (FF)
Bacterial speck Pseudomonas (B)
Root-knot Nematodes (N)
Septoria leaf spot (L)
Tobacco Mosaic Virus (T)
Stemphylium Gray leaf spot (St)
Alternaria Stem Canker/Crown Wilt (A)
The varieties of tomato plants available may seem overwhelming to a new gardener; ask gardening friends for the names of their favorites. This will give you a good idea of what does well in Virginia. Virginia Cooperative Extension Publication 426-480, Vegetables Recommended for Virginia, may also be helpful. Several major types of tomatoes exist that can be chosen according to need:
Tomato plants may be started indoors from seed or transplants may be purchased. If starting your own plants, use a light soil mix and give the plants plenty of light. Tall, spindly transplants are usually caused by low light levels in the home. Unless you have a sunny, south-facing window, supplemental light will probably be necessary. The seeds are sown six to eight weeks before the last frost date in your area. A few weeks before transplanting time, harden-off indoor-grown plants by exposing them to an increasing number of hours outdoors each day. Bring plants in if there is danger of frost. A few varieties of tomato (the sub-arctics) are bred to grow well in low spring temperatures; however, these are rarely available in the usual markets and ordinarily must be grown from seed.
When you are ready to put home-grown or purchased plants into the ground, select stocky transplants about 6 to 10 inches tall. Set tomato transplants in the ground covering the stems so that only two or three sets of true leaves are exposed. Horizontal planting of tomato plants is an effective way to make plants grow stronger, especially leggy ones. Roots will form along the buried portion of the stem, giving better growth and less chance of plant injury from a too-weak stem. Do not remove the containers if they are peat or paper pots, but open or tear off one side to allow roots to get a good start. If non-biodegradable containers are used, knock the plants out of the pots before transplanting, and loosen the roots somewhat. Press the soil firmly around the transplant so that a slight depression is formed for holding water. Pour approximately one pint of starter solution or dilute fish emulsion around each plant to wash the soil around the roots.
Fruit Set. The transition of a flower into a young fruit is very sensitive to several environmental factors over which gardeners have some control. Following is a brief discussion of some of the causes of poor tomato fruit set with particular emphasis on urban gardening.
Temperature and Humidity. Daytime temperatures above 90°F and night temperatures above 70°F result in reduced flowering and fruit set. There is considerable evidence that night temperature is the critical factor in setting tomato fruit, the optimal range being 59° to 68°F. With night temperatures much below or above this critical range, fruiting is reduced or absent. Low temperatures reduce the production and viability of pollen. High temperature, especially if accompanied by low humidity and moisture, hinders fruit set through failure in pollination and/or fertilization.
Plant Nutrition. Reduced fruiting may result from either stunted or excessively vigorous vegetative growth. Injury from disease and insects, especially sucking insects such as aphids and thrips, can severely check growth. Inadequate moisture and/or available nitrogen can hinder growth and flower production. Conversely, abundant water and nitrogen can stimulate rapid vegetative growth with low levels of carbohydrates remaining for the normal processes involved in fruit set.
Garden sites located on heavy subsoils are infertile and poorly drained. Gardeners create faulty nutrition by either not applying any fertilizer or by adding too much. In addition, water for irrigation is often not available during times of drought.
Photoperiod (length of day). Although the tomato plant can flower and fruit at any daylength (day neutral plant), fruit set has been shown to be retarded under continuous light. Thus, tomato fruit set may be reduced under the continuous illumination characteristic of some environments.
DISEASES: Early blight, septoria leafspot, verticillium and fusarium wilts, late blight, tobacco mosaic virus, bacterial spot.
INSECTS: Flea beetle, hornworm, stink bugs, Colorado potato beetle, fruitworm, aphids, mites, whiteflies, cutworms, Japanese beetles.
OTHER PESTS: Nematodes.
CULTURAL: Blossom-end rot, irregular soil moisture or calcium deficiency; poor color, yellow spots or large whitish-gray spots, sunscald from lack of foliage cover; leaf roll, physiological condition often found in pruned tomatoes; fruit cracking, irregular soil moisture; black walnut wilt, caused by roots of tomato plants coming in contact with toxin from black walnut tree.
DAYS TO MATURITY: 55 to 105 days.
HARVEST: Harvest fully vine-ripened but still firm. Picked tomatoes should be placed in shade. Light is not necessary for ripening immature tomatoes but it is necessary for color development. Some green tomatoes may be picked before the first killing frost and stored in a cool (55°F), moist (90% relative humidity) place. When desired, ripen fruits at 70°F.
APPROXIMATE YIELDS: 15 to 45 pounds per 10-foot row.
AMOUNT TO RAISE: 20 to 25 pounds per person if used fresh; 25 to 40 pounds for canning.
STORAGE: Medium-cool (50° to 70°F), moist (90% relative humidity) conditions for one to three weeks for green tomatoes. Cool (45° to 50°F), moist (90% relative humidity) conditions for four to seven days for ripe tomatoes.
PRESERVATION: Can or freeze as sauces or in chunks (whole or quartered), peeled.
Heirloom tomato varieties are treasures from the past. Chosen for outstanding flavor, color, or overall performance, they can be grown in your garden, but probably never found in a supermarket.
With the change in trends of food production after WWII, there came a need to develop tomatoes that could be harvested green, withstand shipping, etc., and maintain a good, uniform appearance. These qualities were achieved through hybridizing. The sacrifice of this breeding was flavor - which, in recent years, scientists have been trying to re-introduce. Though hybridized tomatoes have their place, heirloom tomatoes definitely surpass them in one general characteristic - their taste.
Here are some common heirloom tomato varieties you may want to try:
Check the Internet for current sources of plants, seeds and information, or contact your local Virginia Cooperative Extension Office for sources.
For information on frost protection for tomatoes and other early transplants, see Virginia Cooperative Extension Publication 426-381, Season Extenders.
Virginia Cooperative Extension materials are available for public use, re-print, or citation without further permission, provided the use includes credit to the author and to Virginia Cooperative Extension, Virginia Tech, and Virginia State University.
Issued in furtherance of Cooperative Extension work, Virginia Polytechnic Institute and State University, Virginia State University, and the U.S. Department of Agriculture cooperating. Alan L. Grant, Dean, College of Agriculture and Life Sciences; Edwin J. Jones, Director, Virginia Cooperative Extension, Virginia Tech, Blacksburg; Jewel E. Hairston, Administrator, 1890 Extension Program, Virginia State, Petersburg.
May 1, 2009