How to manage overwintering tomatoes? To prevent the harm of low temperature!

With the advent of the deep winter season, the temperature decreases gradually, and the overwintering tomato cultivated in the greenhouse is facing the test of low temperature. So how to manage overwintering tomatoes? Experts suggest that we must prevent the harm of low temperature!

1. Overwintering tomatoes should guard against low temperature harm

Tomato is a temperature-loving crop, which is vulnerable to low temperature or frost in the process of cultivation in winter and spring. When the greenhouse temperature was 5-10 ℃ for a long time, the leaves of the plants would be dark green or flooded, and if they were kept below 5 ℃ for a long time, the leaves would be albino due to chilling injury.

In order to prevent the harm of low temperature of tomato, on the basis of selecting varieties of cold resistance, low temperature tolerance and low light, the heat preservation of greenhouse should be strengthened, such as thickening soil wall, increasing the density of straw felt, adding buckle small arch shed and so on. In case of sudden cooling, temporary heating measures such as coal-burning stove should be taken. A mixture of brown sugar and potassium dihydrogen phosphate can be sprayed if necessary.

Second, tomato overwintering disinfection

For the overwintering tomato, the low temperature and low light in winter causes excessive humidity in the greenhouse, which creates an extremely favorable environment for the occurrence of various diseases. In this environment, in order to reduce the occurrence of diseases in winter, disinfection before overwintering is particularly important. One of the main goals is to reduce the number of pathogens, strengthen the ability of plants to resist diseases and insect pests, and fundamentally do a good job of prevention. To achieve the purpose of reducing the occurrence of diseases.

III. Fertilizer management of tomato overwintering

The overwintering tomato grows for a long time, and vegetable farmers often apply a large amount of fertilizer, and many greenhouses will appear green moss on the surface after 3 years, that is, soil salinization. If we do not strengthen the management, the soil will worsen, and the output will be reduced year by year, and the whole greenhouse will be abandoned in 7 years. Therefore, attention should be paid to balanced fertilization in the use of fertilizer, and the specific measures are as follows:

When applying base fertilizer before planting, organic fertilizer and inorganic fertilizer must be used together. Mature chicken manure and cow manure were used for organic fertilizer in the newly-built shed, and the amount of inorganic fertilizer per mu was diammonium phosphate, potassium sulfate 5, medium and trace elements fertilizer, calcium fertilizer, and then microbial fertilizer was added. Attention should be paid to the application of inorganic fertilizer 3, 4 and 4 ditches to ensure fertilizer efficiency. In topdressing fertilization, the head ear fruit can choose a large number of elements of medium nitrogen, low phosphorus and high potassium to apply fertilizer 10 kg per mu to promote fruit expansion before cold. Fertilization in the cold season, you can choose rooting, root-raising, cold-resistant alginate chitin fertilizer with plant awakening agents. After the Beginning of Spring, you can choose potassium nitrate with more than 40% potassium content to apply fertilizer 15 kg / mu. In the future, depending on the situation, rinse the fertilizer every other time, and stop topdressing in the last ear when the fruit and eggs are big. Pay attention to the selection of fertilizer to select regular manufacturers to produce chemical fertilizer.

In foliar fertilization, boron fertilizer should be sprayed regularly during the whole flowering period, which can promote the development of flower organs. After hanging the fruit, especially in the peak period, calcium fertilizer can be sprayed to prevent navel rot. Potassium dihydrogen phosphate solution can be sprayed in the later stage of growth to prevent premature senility.

Using aerosol and dust to prevent diseases and insect pests

The diseases of overwintering tomato in continuous rainy days are mostly caused by high humidity and low temperature, so the premise of prevention is not to increase indoor humidity. The effect of using aerosol and dust agent to control diseases and insect pests is good, at the same time, it will not increase the humidity in the greenhouse.

Fifth, rational watering

After watering the overwintering tomato with fixed planting water, slow seedling water should be watered every 2 murals every 3 days. If the slow seedling water is watered late and there is no time to paddle and hoe, the seedlings will grow tall and difficult to cover with plastic film. The first fruit-promoting water is the most critical water, this water early will crazy seedlings, the first ear fruit does not grow big; late watering will fall seedlings, the upper stem is thin and weak, serious premature senility, that is, the imbalance between vegetative growth and reproductive growth. Therefore, the watering time should be controlled at 80% of the head ear fruit in the size of table tennis or eggs. Cold season is generally not watered, if you need to water, then choose to have a few days of sunny weather, small ditch irrigation.