Source(s): Robert R Westerfield, College of Agricultural and Environmental Sciences, Extension Horticulturist
It would be hard to imagine any home garden that did not have at least a few tomato plants. Tomatoes are considered by many to be the most prized vegetable in the garden. There is also plenty of discussion among fellow gardeners as to the best varieties and method of growing each type. This publication will discuss the basics of growing tomatoes successfully, as well as avoiding common problems encountered by the home gardener.
Tomato plants can be started indoors from seed four to seven weeks before they are to be planted. Transplants can also be purchased from a garden center, ready to plant immediately. If starting your own plants from seed, use a light soil mix and give the plants plenty of light. You may need to use supplemental light if a south-facing sunny window is not available for growing. About a week before transplanting, harden-off indoor grown plants by gradually exposing them to an increasing number of hours of light each day.
Tomato plants can be set out in the garden in mid-March to early May after any danger of frost has passed. Some southern areas of Georgia can also produce a second crop of tomatoes when planted in late July.
Tomatoes are warm-season plants that grow best at temperatures of 70 degrees to 80 degrees F and require six to eight hours of sunlight. Choose a sunny location that receives at least eight hours of sunlight each day.
Tomatoes prefer soil that is well-drained and amended heavily with organic matter. Rotted manures, compost, rotted sawdust or other humus can be tilled into the garden site as soon as the soils can be worked in the spring.
Tomatoes require a soil with a pH in the range of 6.2 to 6.8. The pH is the general measurement of acidity in the soil. Soil testing through your local county extension office is the best way to determine the pH. If the pH of the soil is too low, add dolomitic limestone according to the soil recommendations. In the absence of a soil test, apply lime at the rate of 5 pounds per 100 square feet of area. Add lime several months before planting to allow time for it to react with the soil. Till or spade the lime into the soil. Dolomitic limestone also provides calcium and magnesium, which are important elements for the growth and health of the plants. If the pH test comes back normal, but the calcium level is low, apply gypsum at the rate of 1 pound per 100 square feet.
Select only healthy transplants for planting in the garden. Tomatoes can develop roots all along their stems so plant them deeply to encourage a strong root system. Set the transplants down to the first set of true leaves near the soil surface. If transplants are in peat pots, it is not necessary to remove the container, but be sure to plant them deep enough so the pot is not exposed to the soil surface, causing the root ball to dry out. Firm the soil around the plants to force out any air pockets.
Give tomatoes a light amount of fertilizer at planting time. This can be accomplished by using a starter solution of fertilizer. Pour about 1 pint of starter solution (2 tablespoons of 5-10-10 or 5-10-5 fertilizer dissolved in 1 gallon of water) around each plant.
If plants are to be staked or trellised, space them 24 inches apart in rows 4 to 6 feet apart. Although it requires more work initially, staking makes caring for tomatoes easier and keeps the plant’s leaves from contacting the ground and possibly introducing disease. This in turn produces higher quality fruit.
Staking can be done using commercially available cages or by using 6-foot tall, 1-inch square wooden stakes. Drive wooden stakes into the ground about 1 foot deep and 4 to 6 inches from the transplants. Heavy twine or strips of cloth can be used to tie the plants to the stake about every 10 inches vertically as the plants grow. Tomatoes can also be supported by training them to trellises or using a weaving system of cord and stakes.
Tomatoes will benefit from mulch placed around their stems. Mulching should be done soon after transplanting. A material such as weed-free straw, chopped leaves or compost can make an excellent mulch and will help conserve moisture and reduce weed growth. Apply mulch to a depth of 2 to 3 inches. Newspaper can also be used as an effective mulch. Lay the newspaper about three sheets thick around plants to act as a weed barrier and to conserve moisture. Then place an organic mulch on top of the paper.
Synthetic weed barrier rolls are also available and can be very effective in reducing weed problems and conserving moisture. They work best when laid down over beds prior to planting transplants. Small slits can then be made in the material to allow for planting of the transplants. Soil or small stakes may be needed on the edge of the material to secure it during windy conditions.
Tomatoes are medium feeders and will require fertilizer beyond the initial starter solution. It’s best to soil test through your local county extension office to find out the actual requirements for your soil. In the absence of a soil test, incorporate 1.5 pounds of 10-10-10 fertilizer for 100 square feet of bed prior to planting. Use a complete fertilizer that contains minor nutrients. After the first tomatoes form on the vine and are about the size of a quarter, side-dress them with 10-10-10 at the rate of 1 pound per 100 square feet of bed. Repeat every three to four weeks until harvest is completed.
If a liquid soluble fertilizer solution is used, be careful not to apply too much or too frequently as this can lead to excess nitrogen. This is a common problem causing vigorous vegetative shoot growth but few blooms or fruit.
Tomatoes need about 1 to 2 inches of water per week depending on the type of soil they are growing in. If rainfall does not provide this quantity, water plants thoroughly once or twice per week. One or two heavy soakings are better than many light sprinklings.
Consider using drip irrigation or soaker hoses around your plants. These methods will help conserve moisture and avoid getting the foliage wet which can cause disease. Hoses can be laid near each plant above the soil but under the mulch layer.
Harvesting and Handling
For best quality, harvest tomatoes when they are fully ripened on the vine. If harvested before they are ripe, but after they reach the mature green stage, tomatoes can be allowed to ripen in the home.
Place unripe mature green or pink fruit in a room with a temperature of around 70 degrees F. Fruit should be well-ventilated and not jammed together.
Fully ripened fruit may be placed in the refrigerator to prolong keeping, but never put unripened tomatoes in the refrigerator. Tomatoes can last several weeks under refrigeration.