Tomato leaves are curling
Often gardeners complain that the leaves of tomatoes are curled. What it can be – diseases, pests or just the characteristics of the variety, we understand together with our experts

“Most often, the leaves of tomatoes begin to curl when the heat sets in, the air temperature rises above 30 ° C,” explains our permanent expert, agronomist Mikhail Vorobyov. – And in greenhouses, especially where there are few windows and poor ventilation, the temperature can reach up to 45 – 50 ° C. You would also curl up in such a steam room … But seriously, the main reason for twisting the leaves of tomatoes is a violation of agricultural technology, that is, too high a temperature, lack of moisture or nutrition. And the first thing to do when you see twisted leaves on tomatoes is to ventilate the greenhouse.

Why do tomato leaves curl?

But there are many other reasons that lead to the same problem. Let’s analyze each in more detail.

1. Well

When the air temperature in the greenhouse rises above 30 ° C, the tomatoes, in order to at least partially hide from the burning rays, curl up.

What to do. Shade the greenhouse at the peak of the heat, do not close the windows and doors day or night. If possible, install a fan.

2. Insufficient watering

Although tomatoes love warmth and do not particularly need constant watering, plants need to be supplied with water at least once a week, and more often during hot weather. And be sure to shed well under the root of each bush. Unlike cucumbers, which scatter their roots freely at the surface of the earth, tomatoes go deeper. If it is bad to shed the earth, then the plants will not get enough moisture.

Here is an approximate scheme for watering tomatoes in the summer:

  • at a temperature of 16 – 20 ° C – once every 7 – 10 days;
  • at 20 – 25 ° C – once every 5 days;
  • at 25 – 30 ° С – after 2 – 3 days;
  • at 30 ° C and above – focusing on soil moisture: if it dries quickly, then perhaps every day.

The water consumption rate is 1,5 liters per plant (1).

3. Lack of nutrients

Sometimes the leaves curl if the tomatoes lack nutrients.

  • nitrogen – the leaves curl, acquiring a yellowish tint (the way out is to urgently feed with any nitrogen fertilizer);
  • phosphorus – the leaves curl up, from the underside they begin to cast purple (exit – pour over a solution of superphosphate);
  • potassium – the leaves are folded into a “boat”, at the edges there is a brown border (the way out is to feed with any potash fertilizer, for example, potassium sulfate or an extract from wood ash);
  • Copper – the leaves curl up, become covered with yellow blurry spots, with an acute shortage they turn black (the way out is to spray the leaves with a copper-containing preparation, or water the plants with it).

4. Too much fertilizer

And this also affects the fact that the leaves can begin to curl. Especially with an excess of organic fertilizers, for example, a passion for green manure, manure.

  • excess nitrogen – the lower leaves are very powerful, strong, and the upper ones are curly (the solution is to stop all organic top dressing, try to neutralize it with wood shavings or sawdust);
  • excess zinc – the leaves hang, as if from drought, the stem below becomes purple (the solution is to refrain from applying micronutrient fertilizers for at least 3 weeks).

5. Damaged roots

For example, when loosening is too deep, or if a fairly mature plant has already been transplanted. Usually, when transplanting seedlings into greenhouses, its leaves begin to twist slightly – at first this is quite normal, after a week everything should return to normal.

What to do. If the leaves curl due to accidental damage during digging or loosening, water the tomatoes with growth stimulants, rooting and immunity preparations.

6. Wrong pinching

If the stepchildren are not removed in time, this can also lead to leaf curling. If the stepchildren are already large, then this is painful for tomatoes, and they may react by twisting the leaves.

What to do. It is important to remove stepchildren while they are small – 5 – 7 cm long (2).

7. Pests

Basically, the biggest danger is the whitefly. Insects lay their eggs on the reverse side of the leaf, then the larvae secrete sweet saliva, on which soot fungi develop (3), because of which the leaves begin to suffer – curl, turn yellow, fall off.

What to do. This pest is very difficult to deal with. Glue traps for adult insects can be hung in the greenhouse. Treat plants against larvae with Fufanon or Aktara (4).

8. Features of the variety

Mostly curly leaves are found in small-fruited tomatoes, which are grown on the windowsill and in cherry relatives. There is no need to take any methods of struggle – for such varieties this is the norm.

Popular questions and answers

Why do the leaves of tomato seedlings curl?
The reasons may be the same as in adult plants. But most often the problem is a lack or excess of fertilizers and pest damage.
How to feed tomatoes if the leaves are curled?
It depends on how the leaves are curled (see above). In general, tomatoes need to be given good nutrition, which includes all the main elements: nitrogen, phosphorus and potassium. In this case, the problem will not occur.
Will curled leaves recover after tomato treatment?
Be prepared for twisted leaves to not straighten out despite your best efforts. This is fine. Pay attention primarily to the young leaves that began to form after your agricultural activities. If their shape is normal, then your actions were correct.

Sources of

  1. Gavrish S.F. Tomatoes // M.: NIIOZG, Scriptorium 2000 Publishing House LLC, 2003 – 184 p.
  2. Polyanskaya A.M. and a team of authors. Tips for gardeners // Minsk, publishing house “Urozhay”, 1970 – 208 p.
  3. Grebenshchikov S.K. Reference manual on plant protection for gardeners and gardeners // M.: Agropromizdat, 1991 – 208 p.
  4. State catalog of pesticides and agrochemicals permitted for use on the territory of the Federation as of July 6, 2021 // Ministry of Agriculture of the Federation. https://mcx.gov.ru/ministry/departments/departament-rastenievodstva-mekhanizatsii-khimizatsii-i-zashchity-rasteniy/industry-information/info-gosudarstvennaya-usluga-po-gosudarstvennoy-registratsii-pestitsidov-i-agrokhimikatov/

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