What is the specific time in beginning of autumn? When is the start and end date?

Slight cold is the penultimate solar term in the whole year. This is the coldest time of the year, and the growth of crops has entered a difficult and critical period. At this time, farmers' friends are naturally too busy. Let Lao Huangli introduce what farmers should do in the slight cold solar terms.

According to China's meteorological data, slight cold is the lowest temperature solar term, and the extremely cold temperature is lower than slight cold for only a few years. In this season, we should continue to do a good job in the cultivation of spring flowers, do a good job in frost and moisture prevention, and strive for a bumper harvest of spring flowers. In order to prevent snow and freezing rain from damaging bamboo forests and fruit trees, it is foggy and windy in winter, so special attention should be paid to safety when fishing and breeding at sea or in rivers and lakes.

Management of special weather

Clear the snow on the front and rear roofs in time when it snows. Avoid melting snow falling on straw mats or thermal insulation quilts, and reduce their thermal insulation effect. After the snowfall stops, on cloudy days, under the premise that the temperature in the shed is above 12, the straw cover can be uncovered around noon to allow crops to receive scattered light for 2 hours; In case of uncertain weather for a long time, grass leaves should be laid one by one, or insulation materials should be rolled in half to prevent plants from wilting due to too much sunlight; Farming operations such as topdressing, watering, pruning and fruit thinning are not allowed in snowy days and cloudy days. For some greenhouses with large span and poor skeleton stability, it is necessary to support and strengthen the scaffolding in time to prevent it from collapsing when it snows.

In extremely cold weather, in order to ensure the safe production of warm-loving vegetables, temporary heating measures can be taken, such as installing yuba heat conversion light bulb, air heating wire, electric blast furnace, heating combustion block, oil-fired hot stove and so on. In order to avoid the influence of low indoor temperature on crop growth and freezing injury.

Even cloudy and foggy days will have a great negative impact on the environment of solar greenhouse, which will easily lead to the decrease of light intensity, temperature and humidity in the greenhouse. Weak light, low temperature and low humidity are also one of the main reasons for the high incidence of vegetable diseases and insect pests in greenhouse. Therefore, it is an important link to ensure the healthy growth of greenhouse vegetables in winter to take measures such as supplementing light, dehumidification and heating in cloudy or foggy days.

Most of the solar terms for controlling pests and diseases are low temperature and low sunshine. The low temperature and high humidity environment in greenhouse is easy to be infected with diseases and pests such as gray mold, Sclerotinia sclerotiorum, downy mildew, late blight and root-knot nematode. Therefore, we must first adjust the appropriate growth environment conditions. It is particularly important to increase the temperature and supplement the light. At noon on cloudy days, it is necessary to let out the wind for a short time, and sprinkle a layer of dry sawdust or dry straw between rows to absorb excessive air humidity in the greenhouse.

In the early stage of crop disease, chemical agents with low toxicity and residue should be used in time to control pests and diseases, and dust spray and smoke fumigation should be used to control pests and diseases, and spraying should not be used as much as possible to reduce the humidity in the shed. After taking the medicine, it is necessary to strictly abide by the provisions of the safe harvesting interval to ensure the safety of the product.

Always check the storage of vegetables. For stored vegetables such as Chinese cabbage, radish, carrot and celery, always check whether the temperature is appropriate and whether the heat preservation measures are appropriate. If the temperature is too low or too high, the thickness of covering soil layer or thermal insulation material should be increased or decreased in time; Chinese cabbage stored in the pit should be watered regularly and the yellow leaves and rotten leaves should be removed in time.

Organic fertilizers such as chicken manure, pig manure and sheep manure prepared by organic manure composting. Use 5 5- 10/0kg to accelerate the mixing of decomposed biological strains, and turn them once every15th day to reach the standard of complete decomposition and crushing when applying. If the source of organic fertilizer is insufficient, buy commercial organic fertilizer with good quality in advance. In order to improve the quality of vegetable products, it is effective to apply 3000 kg organic fertilizer of decomposed biological bacteria per mu.