What would cause the leaves to curl on a tomatoe plant? It gets plenty of water and otherwise the plant is fine
Tomatoes: Leaves Curling
Many tomatoes experience leaf curl during the hotter parts of the day. It's a natural way for the plant to conserve moisture. If the leaves unfurl in the evenings, then that's what your problem is. If the leaves remain curled, and eventually yellow and drop off, then you probably have a viral, fungal, or bacterial blight of some sort. Nothing you can do about that but to plant varieties that are disease resistant. Spraying fungicides early in the season can help with the fungal blights, but not many fungicides are rated for edibles, and the ones that are have at least a week's period from ceasing spraying to harvest. I don't know about your, but when the harvest gets going good, there isn't any time period that would be safe to spray because I'm constantly harvesting.
Heavy friut set can also cause enough stress to curl leaves,but I fear that the problem is more fungal.If they are not showing any signs of major distress and the fruit is developing normally,then just let nature take it's course.You'll get tomatoes before whatever ails it kills the plant.
I assume it's hot there.
About 90F to95F tomates and many others have a problem called transpiration, This is when the plant looses more water than it can absorb.
Plant in good deep organic mater have less problems.
My OM is 2 1/2 ft deep where I plant my tomatoes, I only get a few days over 100F
But I not longer have that problem..
My Black Krim is doing the same thing. It looks extremely healthy, has fruit and is in great soil, but the top leaves are curled tight. I have tried anti-fungal treatments and today sprayed for possible bugs. Hmmmm.. I will keep checking this post. Amy.
I have read that a potassium deficiency will cause the leaves to curl upward, bunch together tightly and turn dark green. I don't know if this is true but adding a something can't hurt. In the article I read, they recommend potash, wood ashes, greensand, or kelp meal. I'd like to know how this ends
Hope this helps
I have tightly curled leaves caused by aphids. It's funny how they attack some plants but not others. Insecticidal soap helps prevent more curling and I've been pruning off alot of the damaged leaves.
some but not all of my tomato plants are wilting and appear to be dieing .The leaves are turning yellow and the stems are drying up.Wilting away to nothing.there are adjacant plants that still appear healthy I dont think water is a problem and i dont see any insects on the plants .Can you help??
It sounds like Blight
Not much you can do about it; hopefully the fruit will still ripen.
After this season make sure you clean up all of the debris so that it wont linger till next year. Don't put it in the compost pile
Paul, I had the very same problem with my tomato plants this season. Not all of them though...just a selected few. The weird thing was that all around the affected plant were perfectly normal looking plants. That really perplexed me and so I did some investigating on the web and found quite a few causes for my curled up leaves. BTW, curled "up" tomato leaves are called tomato leave roll. When I first spotted the tomato leaf roll, I immediately suspected aphids but upon careful inspection, I couldn't find any. Here's all the info I found. Maybe this will help you and others. It sure helped me. :)
1.) LEAF ROLL IN TOMATOES...Kansas State University
"This season has been one of contrasts--either very hot and dry, or cool and wet--nothing in between. Tomatoes would prefer an even, consistent growing condition, so this year has been a difficult one to manage withoutsome leaf roll. This condition is a physiological malady in tomato plants and not one caused by a disease pathogen or insect pest. The leaf roll is characterized by leaves that roll upward from the outer edges along the long mid-vein of the tomato leaflet. Leaves also may be thicker than normal, more brittle, and the entire plant may have a different coloration-since the underside of leaves isa lighter shade of green than the top. The condition usually starts when tomatoes have finished a period of lush, rapid growth and have begun to set fruit. It seems to be worse in tomatoes that have a fruit load, many blooms, and a little smaller than normal plant size. The tomato plant has a tendency for the top growth and root growth to get "out of synch." In otherwords, under some conditions the tops of plants get much larger than the root system can support. The tendency of the plant is for the leaves to roll up to allow the root system to catch up. The rolling of leaves is a defense mechanism of the plant. We usually don't see this happening until plants are fairly large and setting fruit.The leaf-rolling condition usually persists for only a week or so, before things get back to normal. But under some conditions, plants may stay rolled for a longer time. Leaf roll is worse on tomatoes that are staked or caged than those left on the ground, although staking and caging is certainly a preferred way of growing tomatoes in the home garden. Some varieties of tomatoes are more prone to leaf rolling than others. In looking over a large planting of tomato varieties at one of our branch research stations the other day, I observed everything from severe leaf rolling to practically no leaf rolling at all in plants growing side-by-side and differing only in variety. This does not mean that these varieties are resistant to leaf roll since other conditions may change the variety tendency to leaf roll. Leaf rolling seems to occur worse in poorly drained conditions or following a heavy, soaking rain. Rolling persists longer in lower, poorly drained areas of the garden.It also can develop following an extended dry period when a sudden cooling and rainfall occurs. The lower leaves of the plant start to roll first followed by rolling that extends further up the plant.In some conditions, practically every leaf on the plant may be rolled. Now for the good news. Leaf rolling has generally been shown to be a temporary condition that doesn't result in any significant change in fruit production or fruit quality. There may be a tendency for a little more sunburning to occur when leaf rolling persists into very hot, sunny weather with large fruit hanging on the plant. Avoid deep cultivating or hoeing near the plants since this seems to make the leaf rolling problem worse. Mulching generally seems to help, although we have seen some severe leaf rolling this year on mulched tomatoes. You may find that some leaf drop and/or leaf'riddling' may occur if a strong wind occurs on severely rolled plants. Since the leaves are more brittle and thicker, there may be a tendency for damage of this type to occur."
2.)"When certain tomato varieties are grown for maximum fruit production they often develop a physiologic disorder called leaf roll. Symptoms are most prominent on leaves at the plant base. Leaf margins roll upward until they touch or overlap each other; rolled leaves are firm and leathery to the touch. Supporting and pruning plants, heavy applications of nitrogenous fertilizers, and root pruning (due to close cultivation) are often associated with this disorder. Leaf roll does not noticeably check plant growth or yields."
3.) "Leaf roll of tomato is a very common disorder in many tomato varieties grown in California. Leaf roll does not develop markedly on plants until about the time of fruit setting of the first and second flower clusters. At this time, the older leaves begin to roll upward and inward rather suddenly. Affected leaves are stiff to the touch, brittle, and at times, almost leathery. They are much thicker than normal leaves and shiny on both the upper and lower surfaces. In mild cases, leaves become trough-shaped. In severe cases, the leaves may form a very tight cylinder with the leaf margins touching or overlapping. The severity of leaf roll varies with climatic conditions, cultural practices, and the particular variety grown. No pathogens have been identified as causal agents. When leaf roll is severe, three-fourths of the leaves on a plant may be involved and fruits become exposed to full sunlight, resulting in the development of disorders such as yellow leaf discoloration and sun scald. No control methods for leaf roll are recommended since it is not known to severely damage plants or fruit production and its actual cause is not fully understood. Susceptible varieties have been observed to express leaf roll most frequently when they are grown in staked culture and heavily pruned. Maintaining a high soil moisture content for prolonged periods of time is also believed to accentuate the disorder. Observations of an experiment in Florida led to a hypothesis that leaf roll might be caused by an accumulation of excess amounts of carbohydrates, namely sugars and starch. This theory was tested in the Floradel variety by removing vegetative shoots, flowers, and developing fruits which serve as sinks for photosynthates. These treatments resulted in rapid expression of leaf roll completely to the tops of certain plants. A second test involved growing plants under 0 to 75 percent shade to inhibit photosynthate production. In the treatment under high shade conditions, Home Vegetable Gardening incidence of leaf roll was greatly reduced to less than 50 percent. It was observed that leaves which originally were shaded and did not roll later developed leaf roll when exposed to full sunlight. Although no definite conclusions can be drawn as to the cause-effect relationships of plant carbohydrate concentration to leaf roll, it does appear that leaf roll will be most severe when tomatoes are grown in staked culture under high light intensifies and high soil moisture conditions." Tomato leaf roll, just as the name implies, is the rolling of tomato leaves. This symptom can be the result of excessive or deficient soil moisture,excessive pruning, or excessive accumulation of food materials in the leaves. Varieties like Big Boy, Floramerica, and Beefsteak tend to be affected moreoften then other varieties. Tomato leaf roll is a temporary disorder andsymptoms will disappear and plants will return to normal once the conditions become more favorable for plant growth."
4.)Tomato Leaf Roll
"The edges of leaflets roll inward toward the mid-vein and the leaflet is somewhat leathery to the touch. This is caused by a fluctuation in moisture in the root zone, going from ample moisture to a shortage or by excessive pruning. Fortunately this problem does not adversely affect the production of tomatoes. Leaves remain green and hang on the plant, though affected leaflets do not unroll. If you are irrigating, try to keep the soil moisture level consistent and account for rainfall when irrigating. Some tomato varieties are more susceptible to leaf roll than others, such as Beefsteak, Big Boy and Floramerica."
5.) Leaf Roll On Tomatoes
"What's happening to the leaves on the bottom of my tomato plants? They're rolled up and look terrible -- will my plants still bear fruit?" This has been a common question received by County Extension Offices in recent weeks, and here's what the plant pathologists at Mississippi State University tell us about this problem. Leaf roll isn't a disease that will spread from plant-to-plant, but it is what is referred to as a physiological disease. The condition has been common statewide and is more likely to happen in either very wet seasons or during periods of extended dryness. Since the latter weather conditions have predominated in most areas of the state in recent weeks, leaf roll is probably tied in with dry soils. And as a result, tomato plants are showing an upward rolling of the leaflets of the older leaves. At first, this rolling gives the leaflet a cupped appearance and it continues until the margins of the leaflets touch or even overlap each other. The rolled leaves are firm and leathery to the touch. One half to three-fourths of the foliage may be affected. The growth of the leaf roll tomato plants is not noticeably checked and a normal crop if fruit is generally produced. In most cases, leaf roll occurs in combination with dry soils and when tomato plants are pruned severely. Also, leaf roll may occur following deep, close cultivation. Some varieties are more sensitive to leaf roll than others, but none are completely resistant to this problem. The symptoms on tomatoes are very similar to those of a virus disease of potatoes that is known as leaf roll, but the leaf roll of tomatoes is not caused by virus infection. Suggested control measures which may help avoid leaf roll in a fall crop include:
*Plant tomatoes in a well-drained soil.
*Fertilize according to soil test recommendations and do not over fertilize, particularly with nitrogen containing fertilizers.
*Avoid deep and close cultivation especially in dry weather.
*Maintain uniform soil moisture through irrigation, supplying an inch of water per week.
*Mulch tomatoes with plastic or organic material."
6.) Physiological Leaf Roll
"Physiological leaf roll of tomatoes is a curling and crisping of tomato leaves caused by inconsistent temperatures and watering, not a disease or insect. Our nights are cool, so planting tomatoes in sheltered places and watering in the morning can help not in the evening. Watering in the evening is sometimes essential, but does mean that moisture on the leaves during our very cool nights stresses the plants. If you have a rain barrel with water warmed by the sun in it, so much the better!"
7.) "Another tomato leaf disorder seen in our area is leaf roll. The leaves of the plant roll upward and have a leathery texture. This may be caused by excess moisture, staking and pruning plants, heavy applications of nitrogen, and root damage from close cultivation. Leaf roll is not contagious, and usually doesn't have much of an effect on growth of fruit yield. Herbicide damage is another leaf problem. This results from using 2,4-D or related weed killers too close to tomatoes. Leaves of affected plants often become narrow, twisted and distorted. Stems may split and fruits may develop a catface pattern on them. Plants exposed to small amounts of 2,4-D usually recover, particularly if growing conditions are good."
8.) "Leaf roll of tomato occurs during unfavorable environmental conditions.
Leaf roll is characterized by the upward curling of leaflets on older leaves. At first, leaflets appear to be cupped; this may progress until the margins of the leaflets touch or even overlap each other. Rolled leaves may feel firm and leathery. Symptoms may affect up to three-quarters of the foliage although plant growth and fruit production are not significantly altered. Symptoms are most common when plants have a heavy fruit set.
Persistence And Transmission:
Leaf roll of tomato has been associated with varieties having a specific gene that favors this condition. Tobacco mosaic virus can promote leaf roll symptoms on varieties containing this genetic makeup. High temperatures, prolonged periods of wet soil conditions, and drought may promote symptom development.
Since damage is minimal, controlling leaf roll is not a major concern. Control strategies include the following:
*Set plants on well-drained soil.
*Irrigate during periods of drought."
9.) "Many tomato diseases, including curly top, mosaic, and fusarium , begin with rolling leaves. But if no other symptoms appear, it's probably (aptly named!) tomato leaf roll. It's a temporary disorder resulting from excessively wet soil, especially after heavy rains. It doesn't affect the plant's growth, and a normal crop of fruit is produced. The rolling disappears in a few days when the soil dries out. 'Big Boy', 'Floramerica' and 'Beefsteak' are affected most often."
10.) "Curled leaves could be from aphids feeding on new plant growth by sucking out the plants' juices, causing leaves to pucker or curl."
11.) "If the tip of leaves are brown and internal larvae trails visible with leaves sometimes skeletonized and rolled up, the problem is a leafminer."
12.) "When rain, or irrigation water hits the soil, it splashes some soil onto the tomato leaf. Bacteria is then able to attack the leaf. This tomato leaf can become infected by a bacteria called Pseudomonas. The symptoms of this disease are curled up leaves and black spots."
"Rolling begins on lower leaves and proceeds upwards until most leaves are affected. Plants may lose leaves, particularly on staked plants. Seems to be caused by heavy pruning or deep, close cultivation."
14.) "As the tomatoes develop, a number of leaf problems may also arise. Sometimes you'll see tomato leaves curled up, rolled inward lengthwise along the center vein. This is a normal reaction to cool night temperatures. Generally, the leaf will stay a healthy green and there's no reason to worry about this symptom."
15.) Physiological or Nonparasitic Leaf Roll
"Physiological leaf roll occurs during wet weather or when transplants are first placed outside. Typically, the leaves roll upward, at first appearing cupped but eventually rolling continues until the leaflets overlap. Overall growth of the tomato is usually not affected. Fruit are not injured by this condition. Another type of leaf roll associated with climatic conditions is called" nonparasitic leaf roll". (Note: Physiological leaf roll is also nonparasitic). Nonparasitic leaf roll is considered to be caused by an irregular supply of water or severe pruning. It is a temporary disorder in which the edges of the tomato leaves roll upward and inward, even overlapping when conditions are severe. Most leaves on the plant are affected but the condition is temporary, with the plant assuming normal growth habit within a few days following pruning or irrigation.
Herbicide Damage: Exposure of tomatoes to herbicides, will also cause leaf roll. 2,4-D is the most frequent cause, due to it's common use in lawns, corn, cereal crops, and in pastures. In the past, frequent cases of crop injury were caused by applications of the volatile ester form of 2,4-D. The less volatile amine form of 2,4-D is now more commonly used to reduce the chances of 2,4-D drift. Tomatoes are susceptible to 2,4-D damage through all stages of growth.
Tomato Yellow Leaf Curl Virus: The tomato yellow leaf curl virus (also referred to as tomato leaf curl), is a viral disease that is usually transmitted by sucking insects. This disease tends to be a problem in greenhouse grown tomatoes and is uncommon in plants grown outdoors. If the infection occurs while the plant is still young, the plant will remain small, with terminal and auxiliary shoots remaining upright. Leaves that develop soon after the infection occurs will cup downward, but later leaves will appear chlorotic (yellow) and deformed, with leaf edges cupping upward. Flowers may drop from the plant but their shape remains unaffected. Depending on the time of infection, flowers may fail to set fruit even though they remain on the plant. If the infection occurs while fruit is developing, the fruit will ripen in a nearly normal manner. There is no real control for viral leaf curl. Sucking insects such as the sweet potato whitefly and aphids should be controlled since they are vectors of the disease. ( Keeping in mind, the sweet potato whitefly is a common greenhouse pest but is not found outside in our region). Besides their control, insure that healthy transplants are used and proper cultural conditions are followed. In general, leaf curl on tomatoes will not severely reduce yields. Leaf curl on lower leaves will have a minimal effect on plant growth and yield since these leaves are naturally less important in photosynthesis. If the upper leaves are severely curled and symptoms are apparent early in the plants growth, yields may be reduced."
16.) "What causes tomato leaves to curl upward? The exact cause of tomato leaf roll is not fully known. Tomato leaf roll appears about the time of fruit setting. The leaflets of the older leaves on the lower half of the tomato plant roll upward. This gives the leaflets a cupped appearance with sometimes even the margins touching or overlapping. The overall growth of the plant does not seem to be greatly affected and yields are normal. This condition appears to be most common on staked and pruned plants. It occurs when excessive rainfall or overwatering keeps the soil too wet for too long. It is also related to intensive sunlight which causes carbohydrates to accumulate in the leaves. Some varieties of tomatoes are characteristically curled."
JUST UPDATING THIS THREAD CAUSE IT IS POPULAR QUESTION.
Well.... it might be good to send it back to the top again; even though I copied & pasted it to a text editor.