First, scientific watering. In order to avoid the hollow phenomenon of celery, we must first manage the water. In production, vegetable farmers often cause soil temperature to drop due to the number of times of watering, which affects the normal growth of celery, resulting in insufficient water supply for celery growth. In fact, as long as the watering is appropriate, it will not affect the normal growth of celery. Generally, watering once every 15 days, the amount of water should not be too large, and the water can be slid. Especially in the period of strong growth, we must ensure sufficient water supply, about 15 days before harvest, watering should be sufficient.

Second, control the appropriate temperature. Celery is a cold-tolerant vegetable. It requires cold and humid environmental conditions. Celery is cultivated in the greenhouse. The temperature in the daytime is 15~23°C, and the highest is not more than 25°C. At night, it should be kept at about 10 °C to reduce nutrient consumption and avoid hollowness. But do not let the temperature not be lower than 5 °C, otherwise it is prone to freezing damage and convulsions.

Third, fertilizer management. On the basis of the application of the base fertilizer, the long-term topdressing fertilizer is mainly based on quick-acting nitrogen fertilizer, and combined with the application of potassium fertilizer, the application rate is 20-25 kg per time, and it is chased once every 15 days. Foliar spray application with 0.3% to 0.5% borax solution has obvious effects on preventing the occurrence of hollow disease.

Fourth, timely harvest. Greenhouse-planted celery can not be harvested too late, the harvest period is too late, often cause senescence of petiole, leaf photosynthesis ability declines, the ability of roots to absorb nutrients will also weaken, nutrient deficiency, will also cause petiole thin cells to rupture , causing the occurrence of hollow phenomena.