A courgette plant that flowers heavily but produces little or no fruit is one of the more confusing problems a home gardener runs into, mostly because the plant looks completely healthy while it's happening. The cause is almost always the same thing: courgettes produce separate male and female flowers on the same plant, and for fruit to set, pollen has to move from a male flower to a female one, usually carried by bees.
Early in the season, plants often produce mostly male flowers, sometimes for two or three weeks before the first female flowers appear at all, which reads as a fruiting failure when it's really just a normal, if frustrating, stage of the plant's development. Even once both types are open, a shortage of bees, a run of cold or wet weather that keeps pollinators away, or simple bad timing between when a male and female flower happen to be open can mean pollination never happens naturally.
Telling the two apart is straightforward once you know what to look for. A male flower sits on a long, thin, plain stem. A female flower has a small swollen bulge behind the petals, a miniature courgette, that's visibly there even before the flower opens. If female flowers are appearing and simply shrivelling or rotting without swelling into fruit, that's the pollination failure showing itself directly.
Telling the two apart is straightforward once you know what to look for.
Hand pollination fixes it in under a minute and doesn't require any special equipment. Pick a freshly opened male flower, strip back its petals, and either use a small soft paintbrush to transfer pollen from its centre to the centre of an open female flower, or simply press the male flower's centre directly against the female's, dabbing rather than crushing. Morning is the best time, while flowers are freshly open and pollen is viable. Done every couple of days through a slow patch, it reliably gets a stalled courgette plant fruiting again.
If pollination keeps failing through a whole run of open flowers without you noticing which stage the plant is actually at, that's exactly the kind of timing problem premium check-ins are built to catch: a nudge at the point a plant is flowering heavily but not yet fruiting, rather than discovering weeks later that an entire flush went to waste.