You’ve probably noticed have noticed that squash (zucchinis, pumpkins, gourds, etc.), cucumbers, melons and other cucurbits have both female flowers and male flowers. Female flowers are few in number, but easy to see as they already bear an ovary at the base that looks like a miniature version the fruit that will form. So on a pumpkin, it will be rounded, on a cucumber, long and thin, on a patty pan squash, scallop-shaped, etc. In the center of the female flower, there’ll be a crown-shaped stigma.
Male flowers have no ovary at their base. They are numerous and far outnumber the females. If you look inside, you’ll see they have a “ball” of yellow pollen on a central stamen, absent, of course, in the female. To produce a fruit, the male pollen must somehow be transferred to the stigma of a female flower.
And this transfer has to happen quickly, the same day the flower opens, because each cucurbit flower lasts only one day.
Sometimes, however, pollinating insects are absent when a female flower is in bloom. This can happen if it’s raining that day or if the weather is unusually hot or cold, all conditions that discourage pollinating insects. Or maybe there are simply very few bees or other pollinators that visit your garden.
If so, you need play the role of a bee for the day. Harvest a male flower, remove its petals to better see what you are doing, then use it as if it were a brush, touching the rounded end of the stamen, covered in yellow pollen, to the crown-shaped stigma in the center of the female flower. Alternatively, take an artist’s brush or a cotton swab, touch it to a male flower to coat it with yellow pollen, then “paint” the pollen onto the stigma of the female.
In both cases, you’ll be pollinating the female flower, ensuring its fecundation … and resulting in a beautiful fruit a few weeks later!