Why do flowers drop before fruiting?
Written by
Julia Anderson
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Flower drop before fruiting happens when environmental stresses disrupt plant pollination and fruit set, as high temperatures exceeding 85°F (29°C) cause the pollen to become sterile, and when the humidity is less than 30% the stigmas become desiccated and die. Calcium deficiencies in the plants cause the flower structure to degenerate and die. Knowing these causes at the beginning can often prevent crop losses.
Temperature Control
- Install 30% shade cloth when temperatures exceed 80°F (27°C)
- Use reflective mulches to reduce soil heat absorption
- Water plants early morning to cool roots during heatwaves
Pollination Support
- Hand-pollinate daily between 8-10 AM using soft brushes
- Plant nectar-rich companion flowers to attract pollinators
- Maintain 40-60% humidity with morning misting
Nutrient Management
- Apply foliar calcium sprays at first bud appearance
- Use Epsom salt solution (1 tbsp/gallon) biweekly for magnesium
- Balance NPK ratios to avoid nitrogen dominance during flowering
Preventative measures begin before flowering. Monthly soil pH tests are conducted to maintain a pH level of 6.0 to 6.5, ensuring optimal calcium availability and nutrient balance. Windscreens are installed to shield blossoms. I increased the pepper production by 60 percent by adding gypsum at the time of planting and using shade cloth. Care must be exercised continually during bud formation to develop stiff and strong flowers.
To rescue the affected plants, use recovery techniques. Clip injured blossoms to redirect energy. Apply kelp extracts to inhibit stress hormones. Increase potassium to reinforce the remaining blooms. My zucchinis have survived the cool misting in the afternoons when the weather is too hot. Observe the new tips each day for any evidence of improvement, such as stronger stems.
Choose resistant varieties labeled heat-tolerant or self-pollinated. Cherry tomatoes withstand higher temperatures than beefsteaks. Parthenocarpic cucumbers have fruits that set without pollination. Such varieties ensure the production of satisfactory crops even under challenging conditions. For optimal results, use in conjunction with microclimate management.
Read the full article: 6 Plant Growth Stages Explained Simply
