How do I prevent hollow cucumbers?

Hollow cucumbers are caused by inconsistent watering and heat stress. The main challenge is caused by uneven cell development. In my garden, I solved this problem by installing some drip irrigation that is set on a timer to deliver the water. The plants receive 1 inch of water per week, delivered early in the day, which keeps the soil moisture consistent, preventing the hollow centers.

Check soil temperature with a probe. The optimal soil temperature in the root zone is between 70 and 85°F. When soil temp exceeds 90°F, calcium uptake decreases markedly and hollows develop. I bury sensors approximately 6 inches deep in soil located near plants. In windy conditions, I set up portable fans to increase airflow and reduce soil temperature by 5-7°F.

Mulch thickness is important. In my garden in Arizona, 4 inches of straw mulch kept the soil temperatures at least 10°F less than the bare earth. When using mulch over clay soils, mix in one-part perlite to prevent soil compaction. Also, always keep at least 2 inches between the mulch and the stems of the plants to prevent the stems from rotting.

Address the issue of hollow fruit as it is identified. If hollow fruit is detected, you will want to reduce nitrogen fertilizers and increase calcium. Gypsum is a good source of calcium. Dissolve 1 tbsp gypsum per gallon of water and apply that mixture weekly until harvest. My recovery rate is about 70% when the issue is addressed before the fruit reaches 4 inches long.

Read the full article: How to Grow Cucumbers: Expert Tips for Beginners