Tomatoes are one of the most popular plants to have in a garden. They are very versatile and can be grown in garden plots, raised beds, flower beds, pots and even in some hanging baskets. The plants are relatively easy to grow if you can keep disease and insect pressure under control and are consistent with watering practices. The first step is rotating the location each year because many of the diseases can live over winter on old plant parts or other decaying material in the soil. Second, do not water with overhead watering such as sprinklers. Even watering with a water hose can cause issues if you are splashing soil and water onto the plant leaves. The best method of watering is drip irrigation. Not only does it keep the water at the root zone, but it is also a very efficient means of watering. Third, mulch your plants with bark mulch, hay or straw. They will help conserve the moisture in the soil, eliminate splashing from rainwater and help reduce weed growth.
Other suggestions include staking or caging tomatoes to keep them off the ground, and fertilizing the plants every 3 to 4 weeks. If using a granulated fertilizer, spread it evenly around the plant about 6 inches from the stalks. Incorporating it into the ground will help. When working the soil around the plants, be careful not to go deep enough to damage the shallow feeder roots.
Common Issues in Tomatoes:
Blossom End Rot - This is when the bottom side of the tomato (blossom end) begins to deteriorate or rot when the tomato is still on the vine. It can occur at many different stages of growth. Blossom End Rot is actually a physiological disorder in tomatoes that occurs from calcium deficiencies brought on by water stress. The best management practice to reduce Blossom End Rot is water management using drip irrigation and mulches. Applications of lime or calcium prior to planting can help; and small plots can use liquid fertilizers containing calcium.
Cloudy Spot - This is when we find white or yellow flecks on the fruit. If you peel back the skin you will often find white tissue. This common problem is caused by stink bugs feeding on the fruit at some time during its development. Weed management will definitely help reduce stink bug infestations. If they are severe enough, you may need to implement an insecticidal program.
Radial Cracking – This issue occurs from environmental stress. The symptoms include large cracks that develop from the stem scar where the fruit attaches to the plant. It will usually start appearing in green fruit. Radial cracking can allow for fungal disease to begin appearing on the fruit. Water management and mulching can help reduce the risk of radial cracking and some varieties will crack less than others.
Sour Rot – This is a fungal disease that can be caused by a number of different fungi. Often times it will follow radial cracking or look similar to radial cracking. The lesions will appear from the stem scar and move down the fruit. They will appear water-soaked and often have a white, scummy substance inside the cracks. To reduce the risk of sour rot, drip irrigation and mulching is preferred. Overhead watering can lead to an increased risk of sour rot. Some fungicide sprays can be used if needed, but remember, the sprays will not cure the damaged fruit, but will only serve as more of a preventative or to keep it from spreading.
Whenever you are applying an insecticide, herbicide or fungicide, always follow the label directions. The label will inform you of what vegetables the products can be used on, as well as when you can and cannot spray. Many of the products will have a post-harvest interval which will tell you how many days after application the fruits and vegetables can be harvested and consumed.
Speaking of tomatoes, the Stephenville Organic Gardening Club is hosting its first homegrown tomator contest Saturday at Stephenville City Park. It looks like lots of great sponsors and prizes.
Tomatoes can be grown by conventional or organic methods but must be homegrown (no commercial producers) and you do not need to be a resident of Stephenville or Erath County to enter.
For details, rules and entry forms, call the extension office at 254-965-1460.
Whit Weems is an Erath County extension agent. His column appears weekly and online at yourstephenvilletx.com.