Key Field Management Techniques for Early Spring Carrots
As greenhouse cultivation technology becomes more and more mature today, almost all crops can be grown all year round, and market demand can still be guaranteed. This is the case with carrots: originally, carrots could not be planted in spring and summer, but with greenhouse technology, they can now also be planted in early spring. However, although the growing environment is available, many friends still do not know how to manage them during the growing process. Having a correct field management method can ensure the normal development of carrots. 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 yet fully risen, 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 is fully 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 to the west, close the greenhouse and cover it with straw mats for cold protection and heat preservation.
2. Thinning seedlings at an appropriate spacing
When sowing, be sure to pay attention to the sowing density. The density must not be too high, because too high a density cannot guarantee that each carrot plant has enough nutrients for development, resulting in uneven growth and inconsistent quality. After emergence, seedlings should also be thinned according to the specific situation. When 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 maintain a reasonable and uniform distance between the seedlings, generally about ten centimeters, and one robust 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, open the greenhouse for ventilation. When the temperature gradually begins to drop in the afternoon, close the greenhouse vents. The time for opening the vents for ventilation 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 degrees. 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 growth of the plants caused by too high a temperature.
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 seedling emergence stage. Although watering is needed during fruiting, be careful not to overwater; it is best to spray with a watering can, just enough to moisten the ground. The stage of fleshy root formation is when the water requirement is greatest, and it happens to be during the process of rising temperatures, so a full heavy watering can be given once.
The above is the field management for growing carrots in greenhouses in early spring. Everyone should also pay special attention to the occurrence of pests and diseases during the management process. 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 will easily cause pests and diseases. The prevention and control of pests and diseases is especially troublesome, so everyone must manage well, reduce pathogens, and lower the incidence rate.