What Causes Flower Topping in Zucchini? A Full Breakdown of Prevention and Control Measures
When zucchini is cultivated in greenhouses, flower topping is extremely prone to occur. Once flower topping occurs in zucchini, it seriously affects yield, especially the early yield, which can generally be reduced by 30%~40%. So what causes flower topping in zucchini? How should it be prevented and controlled? Follow along with the editor to learn more.
1. Excessive seedling hardening
Although hardening zucchini seedlings can control top growth and promote root growth, which helps cultivate strong seedlings, if the hardening period is too long, or if the soil is dry, it will lead to poor nutrition at the stem tip growing point and weak growth, causing flower topping at the heart of the plant.
Prevention and control method: The hardening period should be appropriate, and excessive hardening should be avoided. In addition, the soil should not be too dry. In the early stage of flower topping, water timely and in appropriate amounts so that the soil moisture content remains at around 20%. At the same time, apply some quick-acting nitrogen fertilizer with the irrigation water to promote vegetative growth of the plant, or spray gibberellin, which can also promote stem and leaf growth.
2. Low temperature
The suitable growth temperature for zucchini is around 18-25 degrees. Below 15 degrees, its growth will be poor, and below 11 degrees, growth will stop. If cold waves hit in winter and early spring, causing the temperature inside the greenhouse to remain between 11-15 degrees, or even as low as 0 degrees, its growth nodes will also stop growing, leading to disrupted growth and development, causing male flowers to cluster at the top and resulting in flower topping.
Prevention and control method: Temperature must be strictly controlled, especially low nighttime temperatures. Therefore, during the seedling stage and the early planting stage, the nighttime temperature should be kept above 15 degrees. When the temperature is too low, measures such as adding a layer of straw curtains around the greenhouse and building small arched tunnels inside the greenhouse should be taken. If conditions permit, smoke-free heating measures such as laying heating wires or installing electric stoves or burning charcoal can be used.
3. Root damage
Because root damage caused during seedling raising and transplanting, or root rot caused by excessive moisture, as well as root injury caused by excessive fertilization, can also damage the growth nodes and lead to flower topping.
Prevention and control method: When raising seedlings and transplanting, be careful not to damage the roots too much and water appropriately. Especially in cold seasons, water lightly to prevent root rot. Fertilization should be reasonably balanced and must not be blindly excessive, to prevent root burn. In addition, all the small young zucchini at the upper part of the plant should be removed to reduce the plant's burden and help the stems and leaves grow vigorously. For plants with flower topping, harvest mature zucchini in time, and thin flowers and fruits for those with many female flowers or many fruits. Generally, keep 1~2 fruits per vigorous plant.
The above is an introduction to the causes of flower topping in zucchini and its prevention and control measures. We hope it can help you. If you want to learn more related knowledge, please stay tuned to us.