Low or high temperatures, strong winds, rain or other factors affecting bee activity will affect pollination. Poorly pollinated fruit are malformed. There are separate male and female flowers on zucchini and squash plants. The proportion of female flowers varies with temperature, fertiliser application and variety. Fertilisers Table 2 provides fertiliser recommendations.
Daily irrigation is needed on sandy soils.
On heavier soils, irrigate two or three times a week to keep the upper layers of the soil moist. Groundwater pollution Nitrogen, phosphorus and potassium are easily washed through sandy soils by rain and irrigation. Lost fertiliser has been wasted, and phosphorus and nitrogen lost from market gardens may pollute lakes and other waterways. Monitor nutrient levels in the crop using plant analysis. Apply small quantities of fertiliser often.