Tomato leaves are drying out: why? What should I do?

Drying of tomato leaves can have different origins. It is therefore essential to identify the cause to apply the necessary solution when there is a treatment of course because that is not always the case. Let’s take stock of this well-known phenomenon of gardeners and the associated symptoms. Let’s see together how to act when tomato leaves dry up.

Cryptogamic diseases that dry out tomato leaves

Here are the most common causes that can explain why tomato leaves are drying out.


It is unquestionably a frequent problem which bothers people with a vegetable garden. Downy mildew can be daunting because in less than a week it is capable of ruining an entire crop. Mildew is caused by a pathogenic fungus, Phytophthora infestans.

You notice fairly quickly that the leaves take on a greyish or brownish coloringthat their outline seems burnt and that filaments appear on the inner side of the leaves which dry very quickly. The rods are covered with brownish spots. Then the fruits are affected by this scourge, becoming punctuated with mottled bumps so that they have difficulty in ripening.

What favors mildew is by far confinement in a hot and humid environment. You must take the precaution of spacing your tomato plants sufficiently to allow air to circulate in the heart of the plants but also between the plants. We also avoid wetting the foliage. when watering or watering when it is hot. We recommend watering at the foot of the tomatoes, preferably in the evening rather than in the middle of the day. Note that you have to be particularly vigilant during stormy or rainy summers because the temperatures are mild and the humidity is excessive.

When planting, it is useful to place a handful of crushed nettles at the bottom of the hole. Subsequently, as the tomato plants develop, we can use nettle manure in late blight prevention.

In the absence of a preventive solution, it should be noted that mildew can spread very quickly when conditions are favorable. It can therefore attack the whole vegetable garden because the spores of Phytophthora infestans spreads without any difficulty, especially since this pathogenic fungus is able to spend the winter quietly under dead leaves, for example, to better rage the following year.

To treat his tomatoes affected by mildew, there is no solution to exceptional healing powers. In any case, you must start by cutting off all the affected parts and burning them. The rest of the tomato crop should be treated with sprays of Bordeaux mixture widely used by many gardeners.

powdery mildew disease

Here again, it is a disease that can poison the daily lives of gardeners since it too causes deformation of leafletsthe appearance of a white powder coating at the level of the stems, a thinning of shoots. Real havoc on a tomato plantation can be deplored in a short time because of the fungus responsible for powdery mildew. The main factors that favor powdery mildew are confinement of the plants, heat and humidity.

The sick tomato stalks should therefore be addressed as soon as possible. Sprays of a sulfur-based antifungal days when it is not too hot. All affected parts must be removed as soon as possible and then destroyed by burning to prevent the spread of the disease.

Anthracnose or anthrax

This fungal disease is due to the presence of a phytopathogenic fungus of the kind Colletotrichum. In affected tomato plants, brown spots are observed on the foliage which dries up. The leaves appear to have been burned. They don’t take long to fall. In addition, the disease prevents the tomato plant from flowering well, which drastically reduces production. As for ripening tomatoes, they discolor and then their center becomes blackish.

To prevent anthracnose, we try to do not abuse nitrogen-rich fertilizers and we do not wet the tomato leaves. To treat, we use Bordeaux mixture and of course we eliminate all the affected parts which must be destroyed by burning.

Gray rot or botrytis

Other cryptogamic or fungal diseasebotrytis can be recognized by tomato leaves which dry out after the appearance of brown spots, both on the foliage and on the stems which are also covered with a kind of grayish beige felting. Here again, poor ventilation, high temperatures and excessive humidity are conditions which, when combined, favor gray rot due to the fungus. Botrytis cinerea.

Septoria leaf spot

very devastatingthis cryptogamic disease creates serious damage in the rows of tomatoes. It is manifested by round spots that appear on the leaves closest to the ground. It causes them to dry out quickly but also leads to the withering of the entire foliar system in a short time.

In the current state of knowledge, there is no ultra-effective treatment for septoria leaf spot. The affected plants must be pulled out and then burned and it is absolutely necessary to avoid replanting tomatoes in this part of the garden for a few years. At most one can apply a copper-based antifungal at the first signs of the disease to hope to save a few tomatoes.

Brown rot, a bacterial disease that dries out the leaves of tomatoes

Brown rot is also called bacterial wilt. The bacterium in question is Ralstonia solanacearum. The main signs of this bacterial disease are brown mottles on the stems, the leaf wilt which end up falling because they are completely dry. Brown rot attacks young leaves first, then older ones.

on propagation speed is extreme. It affects tomatoes but many other vegetable plants as well. There is no no treatment for brown rot. The only solution to hope to save your vegetable crops is to uproot all the infested plants and burn them.

Even though there are different treatments for fungal diseases that lead to withering of tomato leaves, none can be considered radical. In other words, a 100% success rate has not yet been observed for certain diseases, at least such as mildew, and that’s not to mention bacterial problems. This is why it is essential to provide your tomato crop with the best conditions so that the vines develop smoothly and you can enjoy a harvest of excellent quality fruit.

It may be useful to select tomato plants from resistant varieties, and particularly not very susceptible to diseases, but this does not dispense with regulate your watering and D’sufficiently space the tomato plants. Finally, the gardener wishing to avoid common diseases in the garden must promote crop rotation.

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