Cucumber problems
Fri, Jul 23, 2021

Common Cucumber Pests and Diseases: How to Identify and Treat Correctly

Publisher logo
Common Cucumber Pests and Diseases: How to Identify and Treat Correctly Article Preview
How to Identify and Treat Correctly

Perhaps cucumbers are the most popular representatives of the Cucurbitaceae family among gardeners. A healthy shrub gives a rich harvest and grows well, its leaves are wide and evenly green, the stems are firm. Healthy bushes are capable of fructifying for 2-3 months in a row. Unfortunately, vulnerability to disease and pests can prevent a plant from reaching its full potential. The first step in solving such problems is the competent recognition of the main signs of the disease. There are many diseases and various pests that can harm or even kill the plant. If you want to cure the plant and save the crop, then carefully monitor the condition of the bush. Today we will tell you about common cucumber diseases and subsequent treatment.

Common Cucumber Pests and Diseases

Common Cucumber Pests and Diseases

Wilting of Cucumber Leaves

This is one of the most common problems with growing cucumbers. Cucumber leaves dry out, curl inward, or go down. Gardeners often notice that spots of different localization are formed on the leaf blade. Most wilting problems arise from improper watering, although diseases or pests can sometimes be a major factor as well. Correct diagnosis of the root cause and its rapid elimination can bring plants back to life and prevent the complete death of the plant.

Bacterial Wilt

Symptoms of the disease appear as small light green spots on the lower leaves. Such leaves wither quickly, since bacteria, spreading in the conducting vessels of leaves, petioles, and stems, clog them. The leaves begin to darken and dry out, while the stems remain green.

Watery spots appear on the surface of the stems, over time, the tissue in these places dries up and cracks. The peel of the fruit is in places deformed, brownish, and in the pulp on the cross-section, yellowed points of the vessels are visible. Bacterial wilting occurs more quickly during flowering and fruit formation. At high temperatures and high air humidity in greenhouses, diseased plants wither within 3-5 days. Bacteria are spread by insects (mainly leaf-gnawing and sucking pests). Infection occurs only through mechanical damage to the integumentary tissue (when trimming, pinching).

Cucumber bacterial wilt treatment consists of removing the affected parts of the plant and taking preventive measures to prevent further spread.

Brown Spots on Cucumber Leaves

Brown Spots on Cucumber Leaves

This may be indicative of fungal cucumber plant diseases such as Alternaria leaf blight. Cucumber leaves turning brown, yellow edges appear around the spots. The disease is actively spreading in greenhouses, but it can also affect cucumbers in the open field. Bacterial growth is favored by hot weather, heavy rainfall, and improper watering. The development of bacteriosis at the beginning of fruiting is especially dangerous. Fruits, even if they grow up a little, will be unsuitable for food.

As for the treatment, perhaps the only way is to use fungicide for cucumbers. You can either buy at the nearest suitable store or do it yourself. To do this, you need soapy water, vinegar, and baking soda. But keep in mind that fungicides can make the fruit inedible. So, if only a small part is affected, then carefully cut off those parts to prevent the spread of the fungus. If the plant is already infected quite strongly, then, unfortunately, it is not possible to save it. You may have to remove the plant entirely, replace or cultivate the soil, and start over.

Another disease that is characterized by the appearance of brown angular spots on the leaves, sometimes with yellow edges – Bacterial spots on the leaves. This disease often causes leaves to fall off, which can lead to cucumber blight.

White Spots on Cucumber Leaves

White Spots on Cucumber Leaves

White spots on the leaves of cucumbers often appear in the greenhouse, but can also occur when grown outdoors. Cucumber leaves turn white for various reasons: high temperatures, lack of beneficial nutrients, or insect attacks. But the defeat of white mosaic or powdery mildew can also be the main reason.

Cucumber Mosaic

The virus is spread through aphids, transplants, or contact with unsanitary tools, gloves, and shoes. The symptom is the appearance of white lines and patterns on the leaves. The patterns can also be yellow or light green, and the veins become distinct and yellow.

To get rid of or prevent this viral disease, remove all infected areas and thoroughly disinfect all gardening tools and clothing. As soon as you see insect pests, remove them immediately. We also recommend spraying insecticides containing methoxychlor or carbaryl to control the pest population. You can also use a homemade spray by mixing garlic water and soapy water. Just whisk one head of garlic in a blender with 3-4 glasses of water. Add soapy water to the solution and leave in a dark place overnight. Place leftovers in the refrigerator after use to prevent deterioration of the spray.

Powdery Mildew

No less common cucumber disease, because of which you can observe the white edges on cucumber plant leaves – powdery mildew.

Plaque-like spots are dry first, like flour or mold on cucumber, it can be easily wiped off with your finger. Later it grows, thickens, and becomes covered with small drops of “dew”. With such a disease, cucumber plants die from the bottom up. These spots usually spread from the lower tiers of the plant upwards, as well as from the upper side of the leaves to the lower one. From leaves, plaque passes to stems, petioles, peduncles. With a strong infection, the leaves almost completely turn white, become brittle, curl up and fall off.

For treatment, it is enough to remove the infected parts of the plant and spray them with fungicides. You can use the likes of Curzate, Orondis, Ranman or Zampro. Be sure to read the information on the label before use. If the plant is severely infected, you may need to remove all or most of the plant to keep the disease from spreading.

Yellow Spots on Cucumber Leaves

Yellow Spots on Cucumber Leaves

A change in the color of the leaves of a plant is the main sign that something is wrong with it. Massive yellowing of leaves can be caused by one or more reasons. To minimize yield losses when yellow spots appear on the leaves, you need to be able to recognize common mistakes in plant care, and complex bacterial diseases.

If the lower leaves of the bushes turn yellow, then the reason lies in the lack of light. Most likely, the plants are located close to each other. After the cucumber lashes grew, the light stopped falling on each leaf. The least amount of lighting goes to the lower tier.

The yield from the yellowing of the leaves of the lower level would not be damaged and the plant is not threatened. You simply should inspect the plantings more often and remove the yellow leaves.

For cucumbers, frequent watering is important, but an excess is no less harmful than a deficiency. In dry, hot weather, you should water every day. For an average climatic zone, three times a week is enough.

Water should be supplied in such a volume to moisten the soil for the length of the roots. If there is not enough water, then the lower roots suck out the necessary liquid from the upper layers, the plant begins to wither and the leaves of the cucumber plant turn yellow.

Cucumbers need a lot of nutrients and fertilizers for proper formation and growth. Incorrect and irregular feeding also causes yellowing of the leaves.

What Is Eating My Cucumber Leaves?

Perhaps one of the most difficult problems in growing cucumbers is the emergence of Cucumber beetles. Depending on where you live, you can find either striped or spotted cucumber beetles. Holes in cucumber leaves are left by adult beetles while larvae feed on plant roots.

To prevent the appearance of such pests, initially, it is worth giving preference to such varieties of cucumbers that are resistant to beetles. We recommend you to take a closer look at ‘Gemini’ and ‘Saladin’. You can also place yellow sticky ribbons just above the plant tops to trap bugs. But keep in mind that in this way you run the risk of catching some “beneficial” pollinator insects. Cucumber beetles love Blue Hubbard squash, so plant a few vines of this winter squash to lure the beetles away from your plants.

Why Are My Cucumbers Orange?

Why Are My Cucumbers Orange?

This can happen if you haven’t picked them for a long time and the cucumbers become overripe. The reason for this is the amount of chlorophyll, which decreases after reaching the maximum point of peak ripeness.


Many gardeners, when growing a cucumber plant, often encounter similar problems. Any treatment for cucumber diseases should start with identification because different diseases can have similar symptoms. In cucumber disease control, cut off the infected parts and use fungicides. But do not forget about preventive measures and always disinfect tools and clothing when working with the plant. With enough water and light, healthy soil, and proper care, your plants will delight you not only with their beautiful appearance but also with tasty, healthy fruits.

Do you like this article?
no 0

You can do what you like and get paid! Write articles on the topic you like, work at home with well-paid work!