Fixing Zucchini Blossom-End Rot and Poor Fruit Set

Zucchini that grow to 6 inches then turn black or yellow at the blossom end suffer from blossom-end rot—a symptom of either incomplete pollination or irregular watering (often too much).

Pollination Issues

If bee activity is low, hand-pollinate: transfer pollen from male flowers (straight stems) to female flowers (with tiny fruit at base) using a small brush or cotton swab. Do this the same day the female flower opens. Plant sunflowers, marigolds, or cosmos nearby to attract more pollinators.

Water Management

• Water deeply once or twice a week (1.5 inches total), not lightly daily.
• Mulch heavily with straw or dried grass clippings to conserve moisture and moderate soil temperature.
• Avoid overhead watering to reduce fungal risk.

Soil and Fertilizer

• Fertilize every two weeks with a low-nitrogen, high-phosphorus formula.
• Amend soil in fall with compost, aged manure, shredded leaves, and peat moss to improve drainage and nutrient retention.

With consistent moisture, good pollination, and fertile soil, zucchini will produce abundant, healthy fruit all season.