What to do when greenhouse zucchini only flowers but does not set fruit
This is mainly caused by physiological disorders: first, too much nitrogen fertilizer in the base fertilizer, which promotes excessive growth of zucchini, increases leaf area, and causes severe shading. Second, the temperature inside the greenhouse is too low or too high. Third, the moisture inside the greenhouse is insufficient or the humidity is too high. Such an environment will greatly inhibit the vitality of pollen and styles...
This is mainly caused by physiological disorders: first, too much nitrogen fertilizer in the base fertilizer, which promotes excessive growth of zucchini, increases leaf area, and causes severe shading. Second, the temperature inside the greenhouse is too low or too high. Third, the moisture inside the greenhouse is insufficient or the humidity is too high. Such an environment will greatly inhibit the vitality of pollen and styles. Therefore, the following four measures should be taken for prevention and control.
Improve drainage and irrigation conditions in the greenhouse. Ensure that surface water can drain away and subsurface water can seep away. When fruit begins to set, if there is a drought lasting about 10 consecutive days, then carry out furrow irrigation, but be sure to prevent flooding irrigation.
Increase phosphorus and potassium fertilizer. Generally, spray a 0.2-0.3% potassium dihydrogen phosphate solution once every 5-7 days.
Carry out artificial pollination. Every day at 9-10 a.m., which is the peak period for male flowers to open, pick male flowers, remove their corollas, and gently smear the anthers onto the stigma of the pistil. One male flower can pollinate 3 female flowers.
Hormone treatment. First, use 20-30 mg/L of 2,4-D on the morning of the day of flowering, dip a brush in the solution and apply it to the flower stalk or stigma and ovary, but prevent the solution from splashing onto stems and leaves. Second, use 40-50 mg/L of Tomatotone and spray it on the stigma of female flowers. Third, remove old leaves and thin out residual flowers. The basal leaves at the base should be properly removed, and at the same time, excess female flowers and surplus male flowers should be thinned out.