How to prevent and control late spring cold snaps in vegetables? You need to seize these 3 key periods

“A late spring cold snap” is a weather phenomenon in which early spring temperatures are lower than the same period in a normal year, and crops often suffer frost damage because of it. This kind of “dramatic turn” in the weather is very unfavorable to agricultural production, and if precautions are not taken in time, it is very easy for crops to be frozen. So what measures are there for preventing and controlling late spring cold snaps in vegetables? These 3 key periods must not be missed!

Measures for preventing and controlling late spring cold snaps in vegetables

Preventing and controlling late spring cold snaps in vegetables is divided into 3 parts: first, damage during the vegetable seedling stage; second, damage during the vegetable adult plant stage; and finally, damage during the flowering and fruiting stage. When facing these three kinds of vegetables at different growth stages, we should have different prevention and control measures.

1. Damage during the seedling stage

Symptoms of damage: when the cotyledons are damaged, the edges of the cotyledons lose their green color, and after the temperature recovers they can still grow normally; when the true leaves are damaged, dark green appears at the edges of the leaves, and they will slowly dry up; when the growing point is damaged, the terminal bud will suffer frost damage, and at this time no new leaves will grow anymore, greatly prolonging the plant's slow seedling recovery period. If the weather gradually warms up and the damaged plants still cannot recover, then at this time it is necessary to fill in with new seedlings.

Response measures: cultivate strong seedlings. It is best to harden the seedlings at low temperatures; this can effectively improve the cold resistance of vegetable seedlings, and even if a late spring cold snap occurs, it can reduce the impact of the cold on the seedlings to the greatest extent.

2. Damage during the adult plant stage

Symptoms of damage: the edges often dry up, the plants become wilted, and the relatively tender leaves lose their green color and turn yellow, and so on. Severe freezing will cause the growing point to dry up, and the plant roots will no longer grow new roots.

Response measures: what must be ensured first is not the external conditions, but the plant itself. Only strong vegetable plants can reduce losses when suffering from a late spring cold snap, because strong plants suffer much less damage. When cultivating plants, first do a good job of controlling water and hardening the vegetable seedlings, second allow the vegetable root system to grow strongly, and third apply topdressing to the vegetables to ensure the nutrient needs of the plants during the mid-growth period.

3. Damage during the flowering and fruiting stage

Symptoms of damage: when vegetables suddenly suffer a cold wave or temperature drop during flowering and fruiting, the activity of the pollen of the flowering vegetables will be reduced, which will indirectly affect pollination, fertilization, and so on, and will also cause flower and fruit drop later. During the flowering period, it will also cause poor flower bud differentiation, which will directly lead to deformities in the fruits that grow out. Severely damaged cucurbit vegetables will also develop flowers topping the plant.

Response measures: vegetables that are in the flowering period are relatively delicate, and as long as they are damaged, flower and fruit drop is very likely to occur, and even if fruits form they will be deformed. Therefore, the work that must be done well during this period is prevention, so as to ensure the flowering and fruiting of the vegetables. First, pay timely attention to the local weather, and do not only look at these two days; be sure to look at several days, and it is best to look at the past half month, so as to better take preventive measures. When the temperature begins to change, do not water, so as to avoid frost damage, and promptly prepare the items the vegetables need to get through the cold. Second, when the late spring cold snap arrives, keep them warm in time; only with stable temperature can the vegetables be all right. There are many measures that can be taken, such as setting up some wind-blocking barriers, and also carrying out film mulching on the vegetables. Here, Xiaoshu relatively recommends one, which is rice straw; it can not only protect against the cold but also serve as fertilizer.

Vegetables have different growth periods, so when a late spring cold snap arrives, the growth stages the vegetables are in are all different. They should be handled according to the different growth stages, and the most effective measures should be taken.