What are the precautions for watering vegetables in summer?

In hot summer, especially in July, the temperature is high, the weather is muggy, and the water evaporation is large. So, what are the precautions for watering vegetables in summer?

In summer, there is a saying that "there is a slight drought in three days and a severe drought in five days". Vegetables grown in open fields will experience drought if they are not watered for 3-5 days. For protected vegetables, watering was used to replenish the water lost by evaporation at high temperature to meet the water demand of vegetables and reduce the temperature in greenhouse 2.

1. Time of watering

It is best to start watering at dawn in the morning, and stop watering after 9-10 o'clock when the sun is particularly strong. As the temperature rises, the evaporation of water will take away the heat from the vegetable border, making the temperature in the greenhouse 3-5 ℃ lower than that in the open field. Watering time should be 3-4 days to irrigate once, across ridges (alternating between large and small rows), the amount of water should not be too large. The principle is to increase the frequency of watering and reduce the amount of water.

2. watering and topdressing at the same time

The type and quantity of topdressing are determined according to the growth of vegetables and the harvest of products. Melon and fruit vegetables should be topdressing with water-soluble fertilizer of medium nitrogen, low phosphorus and high potassium at the peak picking period, using 15-20 grams per mu. While watering through the ditch (row), the watering of combined topdressing can also be done by watering once, once, and a small amount of water for many times. In addition, when it rains heavily, do not pour Rain Water into the shed. If it is a large arch shed with plastic film removed, it should be drained in time after the rain, and a drainage ditch should be dug in front of the shed or in the shed.

3. What is a "waterlogged garden"?

Vegetables grow like water and are afraid of waterlogging, especially at noon when it is hot in summer. If there is a sudden thundershower (commonly known as hot rain), in addition to timely drainage, be sure to water the well water again after the hot rain. This is because the well water is relatively cool, by watering the well water can reduce the surface heat, while reducing the ground consolidation, this is the so-called "waterlogging garden". It is particularly important for melons, eggplant fruits and vegetables produced in summer, followed by onions and leeks.

If there is a thunderstorm at noon, if it is not drained in time, it will cause insufficient oxygen in the soil, inhibit root respiration, affect the absorption of water and minerals, and at the same time, anaerobic bacteria will be active, resulting in the accumulation of inorganic and organic acids in the soil and the increase of the concentration of soil solution. some toxic reducing substances such as hydrogen sulfide and ammonia are produced and the roots are poisoned to death. Therefore, when you encounter thunderstorms at noon in summer, you must carry out a "waterlogged garden".

If the water is watered around noon, it is best to discharge the water head that the surface water temperature is too high, which has a good effect on reducing high temperature heat damage.

For onions and leeks, it is more likely to cause dead trees after waterlogging, commonly known as "seedlings". In other words, it is necessary to drain waterlogging in time after heavy rain, carry out waterlogged gardens under certain conditions, and discharge Rain Water without conditions. For the land without drainage conditions, digging a pit on one side of the land as temporary drainage has a certain effect on alleviating waterlogging.