Water greenhouse watermelons once every few days, greenhouse watermelon management techniques

Watering must be carried out according to the water requirements of watermelons. Generally, for watermelons grown in greenhouses, it is more appropriate to water them once every 7 days. When watering in the shed, be sure to do it on a sunny day to avoid encountering rain, snow, strong winds, cooling and other bad weather after watering, which will cause the humidity in the shed to increase and the ground temperature to drop. Under low temperature conditions in early spring, watermelons in greenhouses require relatively little water. When watering, the principle of "no shortage, no watering, prefer dryness to wetness" should be followed.

1. Water melons in greenhouses every few days

1. Watermelons require a relatively large amount of water throughout the growth period, but the water content of the soil cannot be too high. Watermelons have a significant impact on soil moisture. The requirements are that the seedling stage is lower, the spreading stage is higher, and the fruit expansion stage requires the largest amount of water. If sufficient water is not provided during the watermelon fruit expansion period, the yield and quality of the fruit will be affected. Therefore, watering must be based on the water requirements of watermelons. Generally, watermelons grown in greenhouses can be watered once every 7 days.

2. Watering must be done on a sunny day, and bad weather such as rain, snow, strong winds, and cooling must be avoided after watering. These weathers will cause the humidity in the shed to increase and the ground temperature to drop. Do not water in the first two days when the weather suddenly clears up after continuous rainy days. You must first increase the greenhouse and ground temperature to allow the plants to resume normal growth before watering. The watering time can be selected around 10 a.m. on a sunny day.

3. Under low temperature conditions in early spring, greenhouse watermelons generally require less water. Therefore, when watering, you can follow the principle of "no shortage, no watering, rather dry than wet," and keep the soil moisture content at 60 About % is enough. The watering amount of watermelons should be small rather than large, and the watering interval can be appropriately extended according to the situation. Flood irrigation must not be used with large amounts of water. Instead, small amounts of water can be used for frequent watering. This can effectively prevent the temperature in the shed from significantly dropping and the humidity from increasing. Low temperature and high humidity cause watermelon root retting or disease in greenhouses.

2. Greenhouse watermelon management technology

1. From sowing to seedling emergence

(1) During this period, the growth and development mainly rely on the seeds themselves to store nutrients. At this time, the watermelons Moist soil, higher temperatures and good aeration are required.

(2) In terms of management, the ground temperature of 10 cm must be maintained at 25-30°C during the day and 18-23°C at night.

(3) If you encounter rain or snow, clean the snow and other debris on the plastic greenhouse film in time to increase the light and extend the light time as much as possible. If you find that the seedlings have a top shell, you should immediately sprinkle some fine soil and cover them lightly.

2. Emergence to true leaves

(1) This stage is the period when the seedlings transform from autotrophic to heterotrophic. During this period, there must be sufficient light and specificity for emergence. slightly lower temperature.

(2) The temperature must be controlled at around 20°C during the day and around 15°C at night. This allows for slight low-temperature hardening of the seedlings to prevent the hypocotyl from growing too long and forming a long neck. Seedling?.

(3) At the same time, we should also pay attention to proper ventilation, continuously increase the ventilation volume and replace the vents. The covering must be removed early in the morning and covered late in the evening to extend the lighting time as much as possible.

3. 1-3 true leaf stage

(1) At this stage, the leaf buds and flower buds of the watermelon are differentiated at the same time. The growth of the above-ground parts must be properly controlled to promote the root system. Growth and development.

(2) During management, it is necessary to remove the cover early and cover it late, extend the exposure time, increase ventilation volume and ventilation time, and be sure to control the temperature at 20-25°C during the day to facilitate the differentiation of female flowers. .

(3) If most of the seedlings in the seedbed show slight wilting symptoms at noon, you can choose to pour 30-35°C warm water on the border once at around 10 a.m. on a sunny day, and then water the border on the second day. Sprinkle 1 layer of fine sand over the surface to preserve moisture.

4. Harden seedlings before planting

(1) Generally starting from 4-5 days before planting, you can slowly reduce the covering on the small shed in the greenhouse, and at the same time increase the The ventilation time and amount during the day can gradually reduce the temperature of the seedbed to the temperature in the greenhouse and enhance the ability to adapt to the environment in the greenhouse.

(2) 3-4 days before planting, you can pour a small amount of water in the seedbed to prevent soil from spreading and facilitate planting.