Latest Key Field Management Techniques for Early Spring Carrots
As greenhouse cultivation technology becomes more and more mature nowadays, almost all crops can be grown all year round, and market demand can also be guaranteed. Carrots are a case in point: originally carrots could not be grown in spring and summer, but with greenhouse technology, early spring planting is now possible too. However, although the growing environment is available, many friends still do not know how to manage the crop during the growing process. Having a correct field management method can ensure the normal development of carrots, so let us take a look together at the field management for growing carrots in early spring.
1. Cold protection and heat preservation
Although planting and cultivation begin in early spring, the temperature at that time has not fully risen yet, and a low-temperature environment is not conducive to the growth of carrots, so the first thing is to do a good job of cold protection and heat preservation. After sowing, seal the greenhouse for about a week, as this helps the seed germination rate. Then every morning, when the sun has fully come out, open the greenhouse to let sunlight shine directly on the seedlings, and open the straw mats in the greenhouse so they can absorb sunlight and raise the temperature of the field beds. In the afternoon, when the sun gradually moves toward the west, close the greenhouse and cover the straw mats for cold protection and heat preservation.
2. Thinning at an appropriate spacing
When sowing, attention must be paid to sowing density; the density must not be too high, because excessive density will fail to ensure that each carrot plant has enough nutrients for development, resulting in uneven growth and inconsistent quality. After emergence, thinning should also be carried out according to the specific situation. When it is found that the cotyledons of the seedlings have fully unfolded and true leaves have appeared, the first thinning can be carried out at around ten o'clock every morning. The purpose of thinning is to keep a reasonable and uniform distance between each seedling, generally about ten cm, and one vigorous seedling must be left in each hole.
3. Increase ventilation
About half a month after sowing, all the seedlings will have emerged. At this time, at around eight o'clock every morning, when the temperature inside the greenhouse is relatively high, the greenhouse can be opened for ventilation. When the temperature gradually begins to drop in the afternoon, close the greenhouse vents. The time for opening the vents can also gradually move earlier as the temperature rises, and the closing time of the vents can also gradually be delayed. The natural ventilation time will thus gradually increase, and the vents can also begin to be enlarged, keeping the temperature of the field beds at around 20°C. About two weeks before harvest, if the daytime temperature is relatively high, the greenhouse film can be fully uncovered, and then covered again in the afternoon, to avoid excessive vegetative growth of the plants caused by excessively high temperatures.
4. Reasonable watering
Because planting and cultivation begin in early spring, and because the growth cycle of early spring carrots is relatively short and the temperature is still relatively low, watering should not be done too early or in excess; otherwise the water will lower the ground temperature and affect the growth of carrots. If the soil in the greenhouse is relatively moist, there is no need to water during the emergence stage. Although watering is needed when fruit forms, be careful not to overwater; it is best to spray with a watering can and just moisten the ground. The period of fleshy root formation is when water demand is greatest, and it happens to coincide with the process of temperature rising, so a thorough heavy watering can be given once.
The above is the field management for cultivating carrots in greenhouses in early spring. Everyone should also pay special attention to the occurrence of pests and diseases during management. Because spring is when all things revive, pathogens are no exception, so if any one of the above four points is not managed properly, it can easily cause pests and diseases, and the prevention and control of pests and diseases is especially troublesome, so everyone must manage well, reduce pathogens, and lower the incidence rate.