Causes of early bolting of onion and its control measures

After the onion seedlings are planted in autumn or spring, after growing in spring and summer, there are 910 leaves on the ground and a bulb is formed in the underground part, that is, onion. However, some onion seedlings can also shape several leaves before bulb formation, this phenomenon is called early bolting, which will seriously affect the yield and quality. So what is the reason for the early bolting of onions? How to prevent and cure it? Let's take a look.

First, the cause of early bolting

The sensitivity of different varieties to soil temperature is different. The varieties with high yield, low bolting rate and strong sensitivity to low temperature are prone to early bolting. In addition, the amount of nutrient accumulation of overwintering seedlings was also the main factor affecting onion early bolting. Sowing too early, the seedlings grew sturdily, and the bolting rate increased obviously in the low temperature environment for a long time. In addition, the bolting rate of early planting time was higher than that of late planting time, but the bolting rate of late sowing seedlings could also be increased.

II. Prevention and control measures

1. Select varieties with strong winterness

Because the weak winter varieties are sensitive to low temperature, the seedlings can accept low temperature vernalization when they are young, while the strong winter varieties are more sensitive to response, so it is not easy to bolting in advance.

2. Sowing at the right time

Sowing at the right time is also an effective measure to prevent onion from bolting in advance, too late sowing is easy to cause immature bolting in spring, too late sowing is easy to die seedlings during overwintering, and the yield is very low.

3. Timely planting

If the seedlings are planted too early, although the seedlings do not grow much, they can continue to grow when the temperature is high after planting. When the seedlings reach the temperature required for vernalization, it will cause early bolting in spring, so onions must be planted in time.

4. Strict selection of seedlings

The seedlings with height of 12-15 cm, pseudostem diameter of 0.5-0.8 cm, free of diseases and insect pests and seedling age of 50-60 days must be selected when planting. If the seedlings with strong growth are selected, they can be shelved for a few days to inhibit growth, and then colonized to reduce early bolting.

5. Reasonable control of prosperity

In the onion seedling stage to control fertilizer and water, in order to avoid excessive growth of seedlings, when shelved for a few days to inhibit growth, and then colonized, can reduce early bolting.

6. Pick bolts in time

For plants with early bolting, the bolts should be removed from the base of the bolts in time.

The above is the onion bolting reasons and control measures, hope to help you, want to know more related knowledge, please pay attention to us.