Why are my cucumber flowers falling off?
Written by
Paul Reynolds
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Cucumber flowers shedding is often a result of three factors: temperature shifts, improper watering, and poor pollination. I lost 40% of blooms last year due only to nighttime temperatures that chilled below 50 degrees Fahrenheit. I solved that with the installation of low tunnels that raised nighttime temps by only 8 degrees, which I dropped my loses to less than 10%. Consistent treatment alleviates this burden.
Temperature Stress
- Night temps below 50°F: Use row covers or cloches
- Day temps above 95°F: Install 30% shade cloth
- Soil warming: Black plastic mulch boosts root zone 5°F
Watering Errors
- Overhead sprinklers: Switch to drip irrigation
- Wet flowers: Water soil, not plants, before 10 AM
- Dry soil: Maintain 1-inch moisture depth via finger test
Pollination Solutions
- Low bee activity: Plant borage/marigolds nearby
- Hand-pollinate: Use soft brush 9-11 AM daily
- Avoid pesticides: During morning bloom hours
Each morning, check the soil temperature 4 inches down. I use some wireless probes that link to my phone. If the soil is below 55°F, wait until midday to irrigate. On heatwave days, I lightly mist the leaves at noon, noting that a heavy soaking will burn the flowers. Always check the weather apps for frost alerts.
Enhance pollination in your garden easily and naturally! My mason bee houses increased the fruit set of my crop by 25%. The purple coneflowers I planted 3 feet from my cucumber plants attracted 5 times more pollinators than yellow flowers. I would recommend staying away from hybrid varieties that require manual pollination unless you make sure to have the time each day to do it.
Read the full article: How to Grow Cucumbers: Expert Tips for Beginners
