Why does my courgette plant only have male flowers?
Telling male from female at a glance, why a young plant produces males first, and the conditions that delay or abort female flowers.
- Difficulty
- beginner
- Time
- 12 min
- Read
- 3 min
Short answer
A young courgette normally produces male flowers for a week or two before the first females appear. That is not a fault — wait. If females never come, or come and drop, the plant is usually stressed: too little light, too much nitrogen, a pot too small, or roots that keep drying out.
Every courgette and squash plant carries separate male and female flowers, and the ratio changes through the season. Almost every panic about a plant covered in flowers and producing nothing is a plant behaving exactly as it should, a fortnight before it starts cropping.
Step by step
- Learn to tell them apart in two seconds.Look behind the flower, not at it. A female sits on top of a miniature courgette — a swollen embryonic fruit between the stem and the petals. A male has a plain thin stem behind it and nothing swollen.
- Give a young plant time.Most plants produce a run of males first. Females typically start appearing once the plant has made a decent frame of leaves. Two weeks of males only, on a plant that is growing well, is normal.
- Check the light.Courgettes want full sun. A plant in dappled shade or against a north wall makes leaves and males and very few females. This is the commonest genuine cause.
- Check the feeding.A plant in freshly manured ground or on a general nitrogen feed grows enormous and flowers poorly. Once fruiting starts, switch to a high-potash tomato feed.
- Check the root run.In a pot, courgettes need real volume — at least 40 litres per plant, and more is better. A plant that dries out every afternoon aborts female flowers and drops small fruit.
- Water heavily and consistently at the base.Courgettes are among the thirstiest crops in the garden. A soak two or three times a week in dry weather, at the base and never over the leaves, keeps flowering steady.
- Hand pollinate once females arrive if the weather is poor.In a cold or wet spell bees do not fly, so pick a male, strip the petals back and brush the pollen column onto the female stigma, in the morning.
- Use the male flowers.They are excellent food — stuffed, battered or shredded raw. Taking a few does not affect the plant, as long as you leave enough to pollinate the females.
Tips
- Ratio also shifts with weather: cool dull spells push a plant towards more males, warm bright ones towards more females.
- Some F1 varieties are bred to produce a higher proportion of female flowers, which is worth knowing if you are growing in a marginal spot.
- One or two plants is plenty for most households. A third plant is usually a mistake you spend August regretting.
- Pick fruit small and often — 10–15cm. A single marrow left on the plant slows everything down.
Common mistakes
- Removing male flowers thinking they are wasting the plant's energy — The males are how the females get pollinated. Strip them and the fruit aborts.
- Feeding a struggling plant more nitrogen — Nitrogen makes the leaf-versus-flower imbalance worse. High potash is what pushes flowering.
- Judging a three-week-old plant — It is too young to have females. Give it another fortnight before concluding anything is wrong.
Questions people ask
How long before female flowers appear?
Usually a week or two after the first males, on a plant growing well in sun. If a healthy plant is still male-only a month after flowering started, look at light, feeding and root volume.
Can I eat the male flowers?
Yes, and they are considered a delicacy — pick them in the morning when fully open, check for insects, and stuff or batter them. Leave a few on the plant for pollination.
Do I need two plants for pollination?
No. A single plant carries both sexes and pollinates itself as long as a male and a female are open at the same time. Two plants make it more likely that they overlap, which is a small argument for growing a pair.