How do I grow courgettes?
One of the easiest and most productive crops, plus the mildew and pollination problems that occasionally interrupt it.
- Difficulty
- beginner
- Time
- 1 hr
- Read
- 2 min
Short answer
Sow two or three seeds indoors in late spring, plant out after the last frost into rich soil with plenty of space, water at the base and pick every couple of days. Two plants feed a household; three is usually a mistake.
Courgettes are among the most productive things you can grow, which is both the appeal and the warning. The main problems are powdery mildew late in the season and small fruit rotting from poor pollination, both of which are manageable.
What you'll need
- Courgette seed or plants
- Rich soil or a large container
- Compost or manure (optional)
- Watering can (optional)
Step by step
- Sow seeds on their edge, indoors, about a month before the last frost.On edge rather than flat reduces the chance of rotting. Two or three seeds is plenty for a household.
- Harden off and plant out after all risk of frost.They are frost-tender and collapse completely at the first touch of it. There is no rushing this.
- Give each plant at least a square metre.They sprawl much further than the seedling suggests. Crowding causes mildew through poor airflow.
- Plant into soil enriched with compost or well-rotted manure.They are hungry and thirsty. A planting hole filled with compost pays off all season.
- Water generously at the base, not over the leaves.Wet foliage encourages powdery mildew. A sunken pot or bottle next to the plant delivers water to the roots.
- Feed with tomato feed once fruiting starts.Every two weeks. High potassium supports fruit rather than more leaves.
- Pick when 10-15cm long, every couple of days.Regular picking keeps the plant producing. Left to grow into marrows, the plant slows down significantly.
- Hand-pollinate if small fruit yellow and rot.Pick a male flower — the one on a thin stem — strip the petals, and dab it into the female flowers, which have a tiny fruit behind them.
Tips
- Powdery mildew late in the season is almost inevitable and largely cosmetic. Remove the worst leaves and keep watering at the base.
- Courgette flowers are edible and excellent stuffed or fried. Use the male ones so you keep the fruit.
- Two plants is generally sufficient for a family. The classic gardening error is planting six.
Common mistakes
- Planting out before the last frost — They are completely frost-tender and one cold night kills them outright.
- Watering over the leaves — It promotes powdery mildew, which is the main thing that ends the season early.
- Letting fruit grow into marrows — The plant slows production dramatically once it is ripening large fruit. Picking often keeps it going.
Questions people ask
Why are my courgettes rotting when small?
Poor pollination, usually in cool or wet weather when few insects are flying. Hand-pollinate by dabbing a male flower into the female ones — it takes seconds and works reliably.
What is the white powder on my courgette leaves?
Powdery mildew. It is largely unavoidable late in the season. Improve airflow, water at the base rather than overhead, and remove the worst leaves — the plant usually keeps producing.