It would seem that they built a greenhouse or a hotbed according to all the rules of agricultural technology, planted their favorite crops, take care of them all spring and summer, and suddenly the leaves wither, the fruits grow more slowly and not so beautiful, and to top it all off, the plants completely disappear. The cause of this misfortune may be pests – spider mites.
- How formidable is the spider mite?
- Factors affecting the appearance of spider mites in the greenhouse
- How to deal with spider mites in a greenhouse
- Agrotechnical methods of control: prevention comes first
- Folk methods of struggle: cheap, effective, environmentally friendly
- Chemical control methods
- How to save cucumbers from spider mites
How formidable is the spider mite?
The spider mite does not exceed 2 mm in length, its color can vary from milky-transparent color to bright red. This pest can be attributed to arachnids – direct descendants of spiders, ticks and scorpions.
Spiders settle not singly, but in colonies. Female ticks are able to make clutches, in which there will be 400 offspring eggs. They do not live long, up to a maximum of 50 days, but during this time they manage to do a lot of trouble. By the way, tick eggs can live in the ground for up to 5 years.
Spider mite in a greenhouse prefers to be placed on the back of the leaves. They pierce the chosen leaves and thereby suck out the vital juices from them. Light brown or white spots that suddenly appear on the leaves indicate that the spider mite has settled in your greenhouse.
After the appearance of characteristic spots, the leaves turn yellow and dry. Microscopic creatures are able to cope first with all the old adult leaves of crops, and then destroy the tops of the plant along with the fruits and young leaves.
The spider mite infects almost 200 species of agricultural plants and weeds. Cucumbers, peppers, eggplants, melons, pumpkins are especially affected by this pest. Tomatoes, on the contrary, are not afraid of this pest. Oddly enough, but in a greenhouse the probability of damage to plants by a spider mite is higher than in open ground.
Factors affecting the appearance of spider mites in the greenhouse
Unfortunately, it is impossible to completely protect plants in a greenhouse from this pest. A spider mite can get into the structure with a gust of wind, it can be brought on clothes, equipment. It is quite possible to influence the factors that will make his stay in the greenhouse comfortable or unbearable.
The spider mite will multiply rapidly where the temperature is too high and the humidity is low. If you are wondering how to get rid of a spider mite in a greenhouse so that you do not find it again in the spring, then there is a solution to this problem. In autumn, it is necessary to remove all leaves, plant roots and weeds in the greenhouse, carefully dig the soil and disinfect every corner of the greenhouse.
Spider mite survival conditions in the table
|favorable conditions||Temperature 25-29 ºС, humidity 35-55%|
|Unfavourable conditions||Cold, damp and wind|
|reproduction||For a year, an adult gives up to 15 generations.|
|Growth and development||In a month, a sexually mature individual grows from an egg|
How to deal with spider mites in a greenhouse
Despite their small size, these arachnids can cause significant harm. Therefore, the fight against them must begin immediately, as soon as you notice the appearance of uninvited guests in your greenhouse. Even better is to carry out a set of preventive measures before the appearance of these pests among your plants.
Methods for dealing with spider mites are as follows:
Agrotechnical methods of control: prevention comes first
Agrotechnical methods of dealing with spider mites are especially effective in carrying out preventive measures. Qualitatively performed prevention of the appearance of this pest will reliably protect plants from spider mites. The agrotechnical rules for combating spider mites in a greenhouse include:
- Maintaining cleanliness in the greenhouse, timely control of weeds and old leaves, because female ticks hibernate in particles of plants and weeds, under large particles of earth.
- Annual processing of the greenhouse and disinfection of the premises before the start of the new summer season with the help of sulfur checkers and bleach.
- Following the rules of crop rotation: annually alternate plants that are attacked by a spider mite with those that are not afraid of it, for example, plant tomatoes or cabbage in place of cucumbers or peppers next season and vice versa.
- Creating large gaps between rows of plants in a greenhouse in which this pest was seen last year. This will allow timely destruction of infected bushes so that the spider mite does not have time to spread to healthy plants.
- Establishing a climate with high humidity up to 80-85 percent. For plants, this is good, but ticks cannot stand such an environment.
- Regular inspection of plants, especially the back of the leaves. If suspicious leaves are found, they must be destroyed immediately.
- Constant loosening of the soil and its watering.
- Settlement in the infected greenhouse of the natural enemy of the spider mite – the predatory mite phytoseiulus.
- Growing cereals around the greenhouse blocks the access of pests to the structure.
Folk methods of struggle: cheap, effective, environmentally friendly
If the emergence of this pest can be prevented as soon as possible by agrotechnical means of control, then folk methods for the destruction of the spider mite are used when the spider mite has already made its way into the greenhouse and threatens the future crop. When the fruits themselves appear and are soon harvested, the use of chemicals is undesirable, therefore it is best to fight the spider mite with old proven means, environmentally friendly, harmless to plants and fruits, but detrimental to arachnids.
The folk methods of struggle include:
- Watering with tincture of potato tops. Spider mites die within 2-3 hours, but their eggs are not afraid of such irrigation. Therefore, after the first application, it must be repeated several times.
- Irrigation with a decoction of tomato tops and laundry soap. Such irrigation will kill several “hares” – spider mites, aphids and a number of other pests.
- Making and watering plants with onion peel eliminates the pest.
- Irrigation with a decoction of dried leaves, stems and roots of hogweed weed can frighten off arachnids.
- In addition, craftsmen who are versed in herbs use nosed aconite, creeping mustard, common dope, garlic extract, wormwood carpezium, oriental goat’s rue, Manchurian clematis, alder, blue cyanosis.
Chemical control methods
Specialized preparations are used in cases where folk remedies did not help, or pests were noticed too late, and they settled on a large number of plants. The main rule in this case is that fruits from crops sprayed with chemicals can only be removed after at least 3-5 days after irrigation.
Specialists have developed the following acaricides that can effectively deal with spider mites:
- Colloidal sulfur or ground sulfur.
- “BI-58” (effective even when the solution did not get on all the damaged leaves, since the active substance penetrates the plant and moves with its juice throughout the culture, thereby destroying all pests).
- “Vermitek”, “Aktofit”, “Appolo”, “Flumite”, “Fitoferm”, “Aktellik” (if they do not help after several applications, then the pests are used to them, it is necessary to change the drug).
- “Plant-Plin” (has an original form – in the form of a stick, it is buried in the ground next to the roots of plants, when watered, the substance penetrates into crops, and ticks die after 2-3 days).
To achieve the maximum effect, these funds can be used once every 10-15 days, in a neglected state – every 5-10 days. It is necessary to fight the spider mite until it completely leaves the plants in your greenhouse.
How to save cucumbers from spider mites
Most often, from agricultural crops, the spider mite attacks cucumbers. To save the crop, damaged leaves must be removed immediately. Do not water this plant for several days, feed it with nitrogen fertilizers and sprinkle with ash. If these measures did not help, then you need to destroy the entire plant, leaving only healthy cucumbers in the greenhouse, which are best treated with special solutions for prevention.
A spider mite in a greenhouse can be a lot of trouble. High-quality prevention, timely detection of the pest and effective control of it by various methods will allow you to defeat arachnids and save your crop.