Saturday, June 1, 2013

Tomato Problems

I was looking my heirlooms the other day and saw some aphids on the leaves.  It's heating up and problems are starting to arise.  This article will help to identify common tomato problems and solutions.  The good thing, heirloom tomatoes have been around for a long time.  My very simple and unscientific theory is that heirloom strains have been coping with these problems for decades and centuries... they have built up a bit of a resistance to many issues.


Growing fresh tomatoes is one of the true joys of the vegetable gardener. But tomatoes can suffer from all kinds of diseases and pests. Problems growing tomatoes are often the result of weather conditions and small predators lurking under leaves and in the soil. This is something that is out of the gardeners control. Tomato diseases are rarely fatal, if the proper management is employed. It is important to catch any tomato disease early, before it spreads to all of your tomato plants and possibly other plants. Mulching is the most effective way to limit disease.


1. Blossom End Rot

Symptom : This is a common problem with homegrown tomatoes. It initially appears as a depressed, leathery, brownish area the size of a dime to a half dollar on the blossom end of the fruit.

Cause: It is caused by a calcium deficiency coupled with wide fluctuations in available moisture. Training and pruning the tomato vines may also increase blossom end rot.

Remedy: Remove the affected fruit so other fruits on the plant will develop normally. Keep the plants well watered. Mulch to maintain a more uniform moisture supply. Avoid cultivating, or hoeing, near the roots of tomato plants. Some gardeners like to add crushed eggshells to the transplant hole to fortify calcium intake.


2. Yellow Leaves

Symptom: Yellow, uncurled leaves

Cause: If yellow, uncurled leaves appear at the base of a tomato plant, it may just be a sign of the plant aging and beginning to die off from the bottom up. It may also be caused by a nitrogen deficiency in the soil. On occasion, other factors may cause yellow leaves including pest, fungus and bacteria infestations.These three causes usually produce other symptoms besides plain, uncurled, yellow leaves at the base of the plant. For example, if the leaves are turning yellow or brown higher up on the plant, it may be a sign of early blight. Have your soil tested at a local nursery to confirm the nitrogen-deficiency diagnosis.

Remedy: If the soil does have a nitrogen deficiency, supplement the soil with well-rotted manure or compost, both of which are high in nitrogen. You can also apply a nitrogen-rich fertilizer.


3. Flowers Form But Drop Before Fruit Develops

Symptom: Tomato flowers fall off prematurely causing very little or no fruit to actually develop.

Cause:"Blossom Drop" is usually caused when the tomato plant experiences a sudden change in the weather, typically when night temperatures are lower than 13 degrees C, when day temperatures are higher than 35 degrees C, or when night temperatures remain above 24 degrees C. Hot drying winds and a sudden lack of moisture for the plant may intensify the problem.

Remedy: Add mulch to keep the soil moisture even. Use TOMATO BLOSSOM SET SPRAY, an all-natural plant hormone that helps blossoms set fruit in spite of poor weather conditions, producing larger, meatier tomatoes with fewer seeds. Use early in the season and get tomatoes up to three weeks earlier. Spray when tomato flowers are fully open. Improving weather conditions may also solve the problem without action.


4. Shiny, Sticky And Deformed Leaves (Aphids)

Symptom: Leaves are deformed, sometimes yellow, and appear to have a shiny, sticky substance on them. Young tomato plants are especially vulnerable to this "small" problem. Do not confuse this with "rolled" leaves which is a normal occurrence and not harmful to many tomato plants.

Cause: Aphids are small, pear-shaped insects that congregate on the top growth or undersides of leaves. Aphids damage tomatoes by sucking plant sap and excreting a sticky substance on the foliage and fruit. Inspect the deformed leaves or normal leaves in the vicinity and you will be able to see these insects. Whiteflies and spider mites are also nearly invisible insects that can cause similar symptoms and can be treated as described below. Spider mites cause many small yellow specks and fine webs on leaves. Whiteflies will actually take flight when you brush the plant. They may appear as dust or fine residue shaken off the plant.

Remedy: Use NEEM OIL or INSECTICIDAL SOAP CONCENTRATE to control aphids or whiteflies. Removing weeds around the tomato plants will also help.


5. Tomato Skin Splitting Or Cracking

Symptom: The skin of the fruit develops sudden large cracks

Cause: Splitting or cracking typically happens when the fruit experiences accelerated growth, which can be brought on by a sudden increase in moisture after being too dry, like a sudden summer rain after dry periods. Cracking also may occur when the fruit is overripe.
Remedy: The good news is that splitting or cracking does not affect the flavor and the tomato can still be eaten, however unsightly it may appear. To avoid the problem, provide consistent moisture to the plant.


6. Early Blight - Brown Patches On Leaves

Symptom: Black-brownish spots on plant leaves; leaves drop off; sunburned fruits.

Cause: Early Blight is a fungus that survives during the winter on old vines. Cleaning up old vines from the prior season, rotating crops and spacing plants properly to allow for good air circulation are good first steps in avoiding this problem.

Remedy: The preventative measures should be considered first, ie crop rotation and cleaning up debris from prior growing seasons. If you suspect your plants have Early Blight, remove all diseased stems and foliage and dispose of in a trash bag. Do not add to compost pile. BONIDE ALL PURPOSE GARDEN DUST is an effective, organic way to control the disease if caught in the early stages.


7. Late Blight - Brown, Dry, Papery Leaves

Symptom: Water-soaked patches on leaves that turn brown, dry and papery are a sign of late blight. Fruit and stems might be spotted or have blackened areas.

Cause: Late Blight is caused by a fungus that is favored by wet weather and whose spores can travel great distances and infect large areas.

Remedy: The preventative measures should be considered first, crop rotation, proper spacing of plants and pruning to maintain good air circulation around plants. If you suspect your plants have Late Blight, remove all diseased stems and foliage and dispose of in a trash bag. If the area is severely infected, removing all plants and disposing in the trash may be the only solution.


8. Fusarium and Verticillium Wilt

Symptom: Fusarium Wilt causes leaves on one branch of infected plant to wilt and turn yellow. Verticillium Wilt first appears as yellowing between the major veins on mature leaves.

Cause: Both are caused by a fungal infestation. The fungus is inherent in the plant and is not caused or affected by external sources such as weather or care.

Remedy: Unfortunately there is no treatment for a plant infected with Fusarium or Verticillium Wilt. It will spread rapidly through the plant and eventually kill it. The best remedy is to quickly dispose of the entire plant in the trash. Do not add to compost.


9. Nematodes - The (Almost) Invisible Insect

Symptom: Nematodes live in the soil and cause swelling of the plant root, stunted plants and discoloured plant leaves.

Cause: Root-knot nematodes are soil-born microscopic eelworms.

Remedy: The bad news...there is no treatment for an existing nematode infestation. The good news...the affected plants can still grow and produce edible fruit. Preventative measures to stop nematodes in the future include selecting varieties labeled with "N" and planting marigolds with your tomatoes. Many varieties of marigolds, including' Nema-gone', 'Golden Guardian', or 'Tangerine', release a chemical into the soil that kills nematodes. (Left plant normal, Right Infected)


10. Tomato Hornworm

Symptom: Chewed up plant leaves and damaged fruits that are still unripe, huge increase of garden hornets.

Cause: Tomato hornworms are large, green-grayish caterpillars that feed off of tomato fruits and plants.

Remedy: They blend very well with surrounding foliage but they can be extremely large and once you spot them, you'll wonder how you ever missed them. We're talking big enough to saddle these big boys up and let the kids ride around the yard on them!. Pick them off and dispose of them by hand. If infested there is organic caterpillar control.