The common spider mites - Tetranychus urticae - are yellowish green or reddish brown, tiny arachnids. They crawl on four pairs of legs. As with all types of mites, the head, chest and abdomen form an oval body. They prick the plant cells with the bristle-like mouthpiece and suck out the cell sap.
- What are cucumbers - fruits or vegetables?
- Harvesting cucumbers - one should pay attention to this
- How to grow cucumbers successfully
This is how spider mites can be recognized on cucumbers
First, small, bright, pin-pricked dots are visible on the leaves. These increase quickly. In the advanced stage, the leaves turn yellow to gray-brown, dry up and die. In addition, the young cucumber shoots are covered with a fine, whitish web. If you check infested leaves under a magnifying glass, countless, spherical spider mites are visible on the underside of the leaves. For these two reasons, spider mites are particularly common on cucumbers in greenhouses
- too little humidity
- too much nitrogen in the soil
Effective preventive measures: Avoid nitrogen fertilizers. Provide balanced plant nutrition with organic green manure. Increase the humidity in the greenhouse.
Effective control of spider mites on cucumbers
There are enough natural spider mite killers so that you can do without chemicals. Thoroughly shower the infected cucumber plants with lukewarm water. Especially on the underside of the leaves. Then wrap it in a large transparent plastic bag for 2 days. The damp climate destroys the spider mites and the cucumber plants gradually recover.
Spraying the plants with nettle stock and horsetail broth also works. If the infestation is very severe, spray with soapy water or skimmed milk.
Support the natural spider mite killers! Like predatory mites, for example. When using pesticides, look out for products that protect beneficial insects and at the same time prevent cucumber diseases.
If the natural balance is right and the cucumbers are properly cared for, there are enough natural enemies such as predatory mites, wasps, ladybugs, ground beetles, hoverflies and lacewings.
Tips & Tricks
A herb has grown against every cucumber pest. You can place pots of herbs like dill, chives, or garlic between the cucumber plants. In addition, spread the clove powder on the potting soil.