What causes leaf curl on tomato plants?
Environmental stress from bouts of cool rainy weather, herbicide damage, severe pruning, sucking insects and viruses tend to cause tomato leaves to curl.
Yo-yo watering and severe pruning may cause a tomato plant temporarily to develop thick, leathery leaves that curl upwards. In this case, the plant shows no effects on flowering, fruiting or growth. The plant should re-adjust within the week.
Herbicide damage, particularly from 2,4-D, may cause tomato leaves to curl first downwards and then upwards. In this case, the plant may show such effects as cat-faced fruit, stunted growth and twisted leaves. If the exposure is mild or minimal, such effects aren't seen, and any damage will be outgrown.
Herbicide damage may take place a couple of days after the original lawn treatment. It also may occur if the treated lawn is mowed and the clippings are used as mulch.
Sucking insects such as the sweet potato whitefly [Bemisia tabaci] may remove the nutrient-filled products of photosynthesis from a tomato plant. That's why the leaves that they so attack end up yellow in color and deformed in appearance.
Insecticidal soap is an organic control to the pest while an insecticide with the active ingredient esfenvalerate is a more potent control that yields more immediate effects. Insecticidal soap may be used up to the day before harvesting the fruit. With esfenvalerate there must be a day wait between the treatment and the harvest.
Viruses may cause a tomato leaf to cup first downwards and then up. The most recent and most problematic is the Tomato Yellow Leaf Curl virus. It's transmitted by such sucking insects as the sweet potato whitefly, which should be treated as listed above in the paragraph. Accompanying damage to the rest of the plant depends upon when during the tomato plant's growth the virus is transmitted. So it's possible that flowers may or may not wither and that fruit may or may not set.
The presence of the virus is encouraged by such weeds as jimsonweed [Datura stramonium] and nightshade [Atropa belladonna]. As long as such weeds and such plants as the tomato share space, gardeners need to consider the possible continued presence of the Tomato Yellow Leaf Curl virus.
Leaf roll, or leaf curl, is a physiologic distortion that may develop with periods of cool, rainy weather. It cause the lower leaves to roll upward and become thick and leathery. Leaf roll does not affect plant growth or fruit production and requires no treatment.
(See the Related Links below for more information.)
Tomato leaf curl can be caused by a variety of things of which bugs (usually aphids) are only one. Look at the underside of the leaves that are curling. If you don't see aphids, it will either be normal for the leaves to curl or you have a fungus/viral problem. Tomato leaves curl naturally if it's too dry, too hot, too humid or too windy. In other words, the leaves will tend to curl if growing conditions are not optimum for the plant. If it's too hot and dry, water more deeply. If it's too wet, water less frequently (make sure you water deeply though). You can tell if it's a viral or fungal problem by looking at the entire plant, especially the leaves. Tomato leaves differ in color dependent upon the plant. There are some varieties with deep green leaves and others have lighter green leaves. If the leaves are lighter in color than they should be for that variety of tomato, you probably have a viral or fungal infection. The same holds true if you have spotting on the leaves. Cut off a small branch and take it to your local nursery to see what they recommend for your area of the country.
Feeding, for instance aphids; leaf hoppers and rollers, and psyllids. Fungus, for instance nectarines and peaches. Spraying, for instance 2, 4 D drift; or Banvel or Roundup control reactions. Overwatering, for instance tomatoes. Viral, for instance mosaic virus; or squash or tomato yellow leaf curl virus.
Tomato leaf curl can be caused by a variety of things of which bugs (usually aphids) are only one. Look at the underside of the leaves that are curling. If you don't see aphids, it will either be normal for the leaves to curl or you have a fungus/viral problem. Tomato leaves curl naturally if it's too dry, too hot, too humid or too windy. In other words, the leaves will tend to curl if…
The reason depends upon how the plant and its leaves look.  Some upward pointing may be natural, in response to light and sun. This is ka phototropism.  Other upward pointing may be pathological, in response to stress. One such stress is the tomato leaf curl virus. It's spread by whiteflies. An organic control for whiteflies is pyrethrum. A synthetic control is esfenvalerate.  In terms of the virus, there are images on the…
Invertebrates and vertebrates are the animals that eat tomato plants. Examples of invertebrates include aphids, blister beetles, cutworms, earwigs, flea beetles, horn-worms, Japanese beetles, leaf-footed bugs, leaf-hoppers, nematodes, potato beetles, slugs, snails, stink bugs, tomato fruit-worms, two-spotted spider mites, white-flies, and wire-worms. Vertebrates range from chipmunks to deer, mice, rabbits, raccoons, rats, squirrels, voles, and woodchucks.
Tomato Yellow Leaf Click on the links below for tomato-related problems. ~ Lack of iron in the dirt. Esp if using container planting. can be bought and applied at garden store. Tomatoes need EPSOM SALTS to the soil when they start to bud out. Get a bag and read the instructions. Magnesium is so important to the growth and FLAVOR. And also keeps bottom rot away. Over watering or underwatering.Also, calcium and blood meal use…
Liquid Copper Fungicide controls a bunch of fungal diseases, including peach leaf curl, powdery mildew, black spot, rust, fire blight and bacterial leaf spot. Use on vegetables, roses, fruits, and grass. It won't burn plants burn plants. Mix a couple ounces with a gallon of water for most applications.
Leaf curl can be caused by a lack of water or too much heat/ sun. Also, specific to nephthytis leaf curling, are infestations of thrips, a small insect. Infested leaves become curled or distorted, with silver-gray scars or calloused areas where feeding has occurred. Thrips can transmit tomato spotted wilt virus to other plants. check local nurseries, greenhouses, or home improvement stores for pesticides to treat thrips.
Yes, especially if it's unbalanced. For instance, excess nitrogen causes plants to produce lots of leaf at the expense of flowers and roots, and can produce leaf burn. The greatest problem caused by applying more fertilizer than plants can take up, is that rain leaches it out into waterways where it causes rampant plant growth, especially of algae, which block light from the water plants which then die and rot, depleting all the oxygen, so…
There isn't just one kind of leaf beetle; there are numerous types, including the cottonwood leaf beetle, the imported willow leaf beetle, the elm leaf beetle, cereal leaf beetle and asparagus leaf beetle. Leaf beetles attack shrubs, trees, flowers and plants. The leaf beetle is considered a nuisance pest because it mostly causes aesthetic plant damage when it feeds. However, if it feeds on a tree that is in poor health it can cause the…
Bacillus thuringiensis is the main organic control for hornworms [Manduca sexta and M. quinquemaculata] on tomato plants. It's effective. But it's important to make sure that it indeed controls the greatest numbers of hornworms. Specifically, hornworms are feisty defoliators. They know when they're most vulnerable, during the day and on leaf tops. So it's important to check the plant for the defoliating caterpillars quite late in the day. During daylight hours, they often chew in…