When should I sow courgette seeds in the UK?

Late April to early May indoors; late May direct outdoors in southern England. Don't sow too early — courgette seedlings hate cold and grow leggy on a windowsill. Two plants per gardener is usually enough; one for a single person. They produce more than you'll know what to do with.

Why are my courgette flowers not setting fruit?

Either you've only got male flowers (which open first, on long stalks, with no bulge at the base), or the female flowers aren't being pollinated. Male flowers appear 1–2 weeks before females — wait, both will come. If females drop without setting, the weather is too cool or wet for pollinators; hand-pollinate by transferring pollen from a male flower with a small paintbrush.

How big should I let my courgettes grow?

15 cm is the ideal length — tender and full of flavour. Over 20 cm the texture coarsens; over 30 cm they're marrows, which need long cooking and stuffing to be palatable. Pick every two or three days during the peak; miss a week and you'll have marrows whether you wanted them or not.

Can I grow courgettes in containers in the UK?

Yes — bush varieties (Defender, Patio Star) do well in 30-litre containers. Use rich compost; water consistently; feed weekly with a high-potash liquid feed. Place in a sunny sheltered spot. Yields are lower than ground plants but you'll still get more fruit than you need from one plant.

How do I treat powdery mildew on courgettes?

Remove the worst affected leaves to improve airflow. Water only at the base of the plant, never the foliage. Mulch heavily to retain soil moisture — mildew is worse when roots are dry. A milk spray (1 part milk to 9 parts water, weekly) helps; cultivar Defender has good mildew resistance.

Are courgette flowers edible?

Yes — pick male flowers (long thin stems and no fruit forming), stuff or batter and fry. Pick in the morning when they're fully open. Picking male flowers doesn't reduce fruit production; you only need a few to pollinate the females. Female flowers can be eaten with the small courgette attached.

Courgette

Cucurbita pepo

Sow courgette seed indoors from late April, or direct from late May once the soil is warm. Plant out after the last frost: mid-May in southern England, early June in the north. Courgettes are frost-tender (RHS H1c) and need warmth to set fruit. Space them 90 cm apart in rich, deep soil with plenty of compost dug in — they're hungry plants. From late July a single plant produces a fruit every two or three days; pick them at 15 cm before they balloon into marrows. The UK summer suits them perfectly, which is why they're the easiest crop to over-grow. Watch for powdery mildew in dry weather.

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