Tomatoes are a summertime treat and a must-have in the vegetable garden.
By early May, most people have already planted tomato plants or are just now getting started. A lot of work and care is required to get to the point where one can pick a nice lush ripe backyard tomato. Managing insects and diseases is a significant chore, but mulching, watering and staking may be just as critical, if not more important.
Placing mulch around new tomato plants helps control weeds and conserves moisture. It also reduces diseases by reducing the amount of water splashing onto the bottom leaves of the plants. Spread 2 to 3 inches of mulch in a circle around the plants once the soil has warmed up and the plants grow well. Pine straw, grass clippings, newspaper and wheat straw are good choices and decompose as the season progresses. Mulch can be tilled in later in the fall as additional organic matter. Mulch helps to ensure uniform soil moisture and cuts down on the need for frequent watering.
Speaking of water, tomatoes like consistent moisture, rather than fluctuations of too wet or too dry. With frequent rain showers always in the forecast, this can be difficult to control. Hand water or run irrigation long enough to wet the soil 6 inches deep. Adequate moisture will help maintain uniform production and will reduce blossom-end rot. Avoid overhead watering and contact with leaves as much as possible to limit the development of diseases. Invest in drip irrigation or soaker hoses.
Supporting tomato plants in some way as they grow and develop fruit is also necessary. There are many specific techniques for supporting tomato plants; however, the two general methods are staking and caging.
Since determinate tomatoes, like ‘Celebrity,’ do not grow as tall as others, they are most often staked. With staking, all flower clusters on a tomato plant usually develop on the same side of the stem. A stake should be placed so that the developing fruits are not crowded between the main stem and the stake. Therefore, do not stake plants until after the first flower cluster is formed. Then, drive the stake on the side opposite of the flower cluster and about 4 inches away from the base of the plant. Tie the stem just above the first flower cluster, using strong binder twine or cloth strips. Staked tomatoes will usually produce ripe tomatoes earlier in the season than caged tomatoes.
Indeterminate tomato plants, like ‘Better Boy,’ do better if surrounded by wire cages; however, a cage should be sturdy and well anchored to the ground. Concrete reinforcing wire provides good support for the plants. A cage should be 24 inches in diameter. A length of wire 9 to 10 feet can be used to construct a cage within that size range. In general, a caged tomato plant will produce more but smaller-sized fruit than a staked tomato plant.
It is also vital to visit the vegetable garden daily to check how well it is growing and detect potential problems. Two common diseases that may occur early in the year are the Tomato Spotted Wilt Virus and early blight. Most tomato diseases, with only the exception of a few, can be prevented or controlled. If not prevented or detected early, these diseases can be headaches for gardeners and farmers.
TSWV is a serious disease found on tomatoes because there is no cure. Once found, gardeners must yank up the infected plant and discard it.
The first noticeable sign is that the tomato plant stops growing and tends to be much shorter than the healthy plants around it. Plants infected with TSWV exhibit dark purplish-gray ring spots on the leaves in the terminal portion of the plant. Later, the dark spots merge and cause the leaves to appear bronze. Infected fruit may exhibit numerous ring spots and blotches and may become distorted if infected when immature.
TSWV spreads by insects called thrips. Controlling thrips to prevent and reduce the spread of TSWV is the only strategy. Spray tomatoes with an insecticide, such as malathion, neem or insecticidal soap, to suppress insect populations and the spread of TSWV. At the first sign of TSWV, always remove and destroy all infected plants as soon as symptoms appear. Leaving an infected plant serves as a new source for the disease and only aids in spreading the virus. Sacrificing one or a few may help save the others. New tomato cultivars are developing a resistance to TSWV.
Early blight is usually the first disease that attacks tomato plants each year. As its name states, this fungal disease appears early in the growing season as spots on the older lower leaves and causes them to yellow and die. It slowly spreads and moves up the plant onto the rest of the leaves. In addition to moving up the individual tomato plant, early blight also spreads to other existing tomato plants in the garden. A severe case of early blight will stunt plant growth and limit much of the fruit production.
The best way to deal with early blight is to prepare and control it early. One cultural method is to make sure mulch is placed around the plants throughout the garden. Since early blight is a fungal disease and spreads through spores, mulch will help limit the amount of water and spores that splatters on the plant during rainfall and overhead irrigation.
As mentioned above, it is best to put the water around the base of the plants near the ground rather than sprinkling overhead. Excess water on the leaves combined with high humidity could help trigger fungal growth and early blight.
Fungicides containing chlorothalonil, commonly sold as Daconil, are recommended for the prevention and control of early blight and other vegetable fungal diseases. Once the young tomato plants are about a foot tall, consider starting a fungicide spray program. At the first noticeable sign of early blight, pick off the affected leaves and begin spraying. If early blight has been a problem in the past, more than likely, it will re-appear each season.
Lastly, scout regularly for insect infestations. Most garden bugs are not overly devastating to tomatoes, but do be on the lookout for aphids, stinkbugs and caterpillars. These can cause damage with long-term effects and require quick action before the problem and numbers get worse.
Homegrown tomatoes can be a real treat or a real headache. The treat is eating and enjoying that nice red and ripe tomato. The journey to getting to that point and actually harvesting one or two can be a challenge. Contact me or your local County Extension office for additional growing advice or help with any problems that might arise.
A BLT sandwich would be really nice this summer; I just hope we all can again successfully grow them “T’s.”
~Shane Harris is the County Extension Coordinator for Tallapoosa County.