Hand pollination is the manual transfer of pollen from the stamen of one plant to the pistil of another–that is from a male flower to a female flower.
Members of the Cucurbit family–squash, melons, pumpkins, and cucumbers–often have pollination problems because the male flowers commonly open days before the female flowers and so often drop before pollinators such as bees can transfer pollen from male to female flowers.
When female flowers are not pollinated, the fruit will never appear. The nascent fruits–bulging embryos–at the stem end of female flowers will shrivel and die if not pollinated.
If fruit is not forming on your Cucurbit family plants, you can help. Rub a small brush or cotton swab on the stamen of a male flower (it will be dusty with pollen) then rub the brush on the stigma of the female flower.
Alternatively, you can remove the petals from a male flower and brush the stamen against the stigma of a female flower.
Which flower is male and which is female? Female flowers have a small bulge (a small immature flower) where the stem meets the flower. Male flowers are shorter than female flowers and often appear in clusters.
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