When do onions be watered in spring

Onions are generally watered before and after Ching Ming Festival, but can be watered every 10 days or so with the rise of temperature in spring. During the period of phosphorus stem expansion, it should be watered every 5 days, and the watering should be stopped about a week before harvest.

First, timely watering

1. Onions are usually planted in autumn. in order to ensure that onions survive the winter safely, they must be watered with enough water after planting.

2. Onions enter the green period in mid-March of spring, and can be watered before and after Ching Ming Festival. With the gradual rise of temperature, onions enter a period of rapid growth. In order to promote the rapid growth of onions, they can be watered every 10 days or so.

3. Onions need a lot of water during the phosphorus stem expansion period, about every 5 days or so, and should be stopped about 7-10 days before harvest.

II. Rational fertilization

The main results are as follows: 1. In order to promote the rapid growth of onion, fertilization can be carried out in stages. If sufficient base fertilizer is applied before onion planting, there is no need to apply early fertilizer.

2. when the plant is growing rapidly, organic fertilizer should be applied, the amount of organic fertilizer per mu is about 4000 jin, and applied with phosphorus and potassium fertilizer at the same time, nitrogen fertilizer should not be applied too much during fertilization, which can easily lead to excessive leaf growth and early smoking.

3. In the period of phosphorus stem expansion, the second topdressing can be carried out. In order to promote the growth of the underground part, phosphorus and potassium fertilizer is mainly applied.

Third, cultivate the soil by ploughing.

The main results are as follows: 1. in order to enhance soil permeability and improve nutrient utilization, soil cultivation should be carried out in time, which is beneficial to promote the expansion of phosphorus stem and increase the yield.

2, wait until the onion seedling stage, need to appropriately increase the frequency of loosening soil, at least 4 times, in the onion stem and leaf growth period, can appropriately reduce the frequency of loosening soil, about 1-2 times on it.

3. Pay attention to when loosening the soil and cultivating the soil, do not damage the underground phosphorus stem of onion, so as not to affect the quality of onion, so shallow ploughing is better.

Fourth, removing bolting

The main results are as follows: 1. during the growing period of onion, the phenomenon of early bolting will appear, and bud picking and bolting can be carried out properly, which is beneficial to promote the growth of lateral buds and enlarge the underground phosphorus stem, thus increasing the yield of onion.

2. Generally, when the onion is budding, it should not be removed too early before the flower ball is formed, otherwise it will affect the normal growth of the onion.

V. Prevention and control of diseases and insect pests

1. The common diseases of onion are purple spot, leaf blight and so on. If the disease is found, it must be controlled in time, and it is not suitable for continuous cropping.

2. The seeds can be mixed with carbendazim before planting, and at the initial stage of the disease, chlorothalonil or mancozeb can be sprayed for control.

3. For the control of thrips and seed flies, deltamethrin can be sprayed.