Contents
The greenhouse makes it possible to grow heat-loving plants or simply harvest vegetables much earlier than weather and climatic conditions allow. But heat, combined with humidity, breeds pests and disease-causing organisms that can overwinter and jeopardize next year’s crop. That is why in the fall, after the end of the season and in the spring, before planting, the greenhouse is not only cleaned, but also treated with special means.
Why process
The preparation of the greenhouse begins in early spring, long before the moment of planting plants in it, while snow dominates the garden, and the seedlings are just about to sprout on the windowsills. The main cleaning is done in the fall, when, after harvesting, all plant residues are removed. If the plants suffered from any diseases or attention of harmful insects, it is quite possible that the larvae of these pests, pathogenic plants or spores remained overwintering in the upper layers of the soil, on walls, ceilings, shelves, implements, props and garter materials. When creating favorable conditions, they will certainly be active, which means that next year’s harvest will be in jeopardy.
That is why the greenhouse after the winter is not only repaired and cleaned, but a number of disinfection measures are carried out. In addition, care must be taken to increase soil fertility, it is hardly possible to leave it fallow for several years, and nutrients are depleted year by year.
Vegetable tops, flower stems – any greens that have been grown indoors should not be left, hoping that it will become fertilizer, especially if the plants have suffered diseases. Such plant residues can do more harm than good, they need to be removed, but rather destroyed. Fungal spores, harmful bacteria, larvae and eggs of pests are very small, they can hide on pegs, props, garter ropes, in the slightest cracks at the joints of walls and ceilings. You cannot get rid of them by adhering to the rules of crop rotation or by sowing green manure before planting the main crops. These activities should be combined with the chemical treatment of the entire greenhouse in the spring against those infections and pests that were seen on plants during the growing season.
Replacing the top fertile layer of the earth will also help get rid of harmful microorganisms and will increase the yield. If it is not possible to do this, you can collect a layer of soil, 10-15 cm thick, heat it over a fire, and then mix it with complex fertilizers. It must be remembered that it is possible to cultivate the land with chemicals only in the fall, but not in the spring before planting. In the spring, you can only use a solution of copper sulfate or Bordeaux mixture.
Video “Soil preparation in a greenhouse after winter”
How to prepare the soil for planting after winter and how to degrease it with Fitosporin is described in this video.
Cleaning
First of all, the greenhouse after winter should be carefully examined. In the process, it will certainly be discovered that somewhere something is rotten or broken. Therefore, it is necessary to correct and replace all damaged or defective elements. Racks, shelves, partitions are corrected, replaced, painted. All glass sheets must be thoroughly washed on both sides with any product created for this, washing off with a strong stream of water to allow the maximum amount of sunlight possible. Film or polycarbonate coatings that have not been removed for the winter are carefully inspected and washed with soapy water. The film, quite possibly, needs to be replaced somewhere.
Most likely, the ground in the greenhouse is still covered with snow. Some owners, after autumn cleaning, dig up the soil, and then throw it with pure snow, which lies there all winter. In early spring, when cleaning, you need to speed up the melting process, for this the snow is covered with something black, it can be just earth, humus, compost or ash. It is enough to scatter a thin layer so that the white snow does not reflect sunlight. If you use heaters, the process will go faster.
When the earth warms up enough to be able to be dug up, it is time to move on to disinfection, that is, the treatment of the greenhouse itself and the soil inside it with substances that will protect future plants from diseases and pests.
disinfection
If the plants suffered from some diseases, then the main fight against them and their distributors takes place in the fall after harvesting. In the spring, a milder preventive treatment is carried out. So if last season vegetables were sick with late blight, black leg, white rot, clubroot, a gall nematode was found, then bleach is used. Even if a good treatment was carried out by her in the fall, in the spring it is worth spraying everything with a liquid solution. First, 10 g of lime are thoroughly mixed in 400 liters of water, and then they are allowed to stand for at least 4 hours. Transparent walls and roofs are treated with water that has settled from above, and wooden structures with sediment.
At least 1 month before the appearance of plants in the greenhouse, it can be treated with carbation. This is done if keel, root rot, black leg, fusarium or verticillium wilt have been noticed. 2 liters of carbation cultivate 1 square meter of land, then dig it up.
If you need to act on the spider mite, mold, whitefly larvae, use a formalin solution. They are treated with greenhouses at a temperature not higher than 10 – 12 degrees, otherwise it will simply disappear, but it needs to be inside for some time. A forty percent solution of formalin is poured over the entire area (a person should only work in a gas mask), and after that it is desirable to increase the temperature in a tightly closed greenhouse to +25 degrees. It is advisable to keep the greenhouse closed for at least a day, only after that it is well ventilated. Formalin can also be used only a month before settling seedlings in the greenhouse. It is said that the formalin is somehow retained (or even concentrated) in the concrete, so if possible, it is best not to water the concrete elements with it.
Prevention against diseases such as all kinds of bacteriosis, powdery mildew, various rot and spotting, late blight, rust, curl, scab is carried out with copper sulphate. In autumn, a large dose of strong concentration is used, and in spring it is enough to take a ten percent solution, spray it with the entire inside of the greenhouse.
Of course, the chemical industry has created special preparations to fight certain bacteria that carry and provoke diseases. This is “Fitoflavin-300” – against all kinds of rot, “Baileton” – against alternariosis, powdery mildew, gray rot, “Acrobat MC” – against late blight and downy mildew. All of them have proven themselves well, the main thing is to carefully study the instructions before use. Not all drugs can be used in the spring.
The most common spring disinfectant is sulfur. Along the entire length of the building, lumps of sulfur are laid out on metal sheets, poured with kerosene (or smoldering coals are placed nearby) and set on fire. Take approximately 50 – 80 g per 1 cubic meter of area, if among the alleged pests there may be a spider mite, the dose is doubled. Processing is carried out only after all the cracks and crevices have been caulked to ensure tightness. Keep the room closed for at least 3 days. Of course, the person who does all this must provide protection methods – a respirator, goggles, gloves (and preferably a protective suit and a gas mask), since smoke is very dangerous not only for pests. There are special smoke sulfur bombs that are more convenient to use. Sulfur, or rather its smoke, has a destructive effect on metal, so it is better not to process greenhouses with a metal frame.
It must be said that it is necessary to do the disinfection of the greenhouse in the spring, but it is advisable to focus only on those diseases and those pests that have been accurately noticed, the excess exposure to poisons will not do any good.
All those things that will be next to the plants can bring them infection, so it is worth remembering and carefully processing all tools, utensils and other equipment. Copper sulfate (50%) or bleach (50 g per 1 liter of water) are perfect for this.
Wooden structures can be treated with copper sulphate, and then whitewashed with lime, while metal structures can simply be scalded with boiling water.
The best way to prevent the spread of diseases is to completely replace the soil, but this is rarely possible. Usually, after all the disinfecting measures in the greenhouse, the earth is shed with boiling water, then dug up, adding a spring dose of fertilizer.
Video “Greenhouse treatment from phytophthora”
The correctness of the processing of the greenhouse from phytophthora is discussed in the video.
