Solving Tomato Problems
By Jodi Torpey
If you’ve struggled with your tomato crop this season, raise your hand.
It’s been a tough tomato-growing year because of the long months of cool, wet weather. Tomatoes are tropical plants and they grow best with warm temperatures during the day that carry over into night.
This season tomato crops may mature later than usual, so let’s hope for a few more months of warm weather into fall. Until then, here are some common tomato problems you might see in your vegetable garden and what to do about them:
Leaves are curled with purple veins? The plant may be infested with psyllids, tiny insects that feed on the plants, causing leaves to yellow and curl. In extreme cases, psyllids can stop the plant from growing and producing fruit. Look for the pests on the underside of leaves and wash off with a blast of water from the hose or apply insecticidal soap as a control.
Missing leaves? Look for tomato hornworms, the large green caterpillars with white markings and a horn on one end. Hornworms are hard to spot, so look for large areas where leaves are missing. Pick off the pests or use a trowel to knock them into a bucket of soapy water.
Irregularly shaped watery spots on leaves? If the spots are on the younger leaves growing at the top of the plant, the likely problem is late blight. This is a fungus that infects tomato plants in the late part of summer when the weather starts to cool. Avoid late blight at planting time by spacing tomatoes as far apart as possible for good air flow, water only at soil level and removed diseased plants from the garden right away.
Tan or dark soggy spots? This is blossom-end rot that can ruin tomatoes. It’s not a disease but a problem with low calcium in the soil and inconsistent soil moisture (see picture below). To prevent, keep soil evenly moist to help the plant take up calcium, especially when the weather is dry. A thick layer of organic mulch (like straw or dry shredded leaves) will help regulate soil moisture.
Cracks? Cracks usually form in tomatoes along the side starting at the stem. Cracking is usually caused by rapid growth because of wet weather followed quickly by dry weather and hot temperatures. Use a soaker hose for consistent moisture and apply more mulch.
Holes in fruit? One big hole could signal a squirrel enjoyed a bite of tomato; smaller holes may have been caused by a fruitworm that may or may not remain in the fruit. If you see only one tomato affected, remove it from the plant; if there are holes in many of the tomatoes, you may need to apply Bt. Keep in mind that worms already inside tomatoes won’t be affected.
Even if the tomato crop doesn’t measure up this season, there’s always next year!