How to Grow Courgettes: Seed to Harvest Guide

Why Courgettes Are Worth Growing

Courgettes are easy to grow and fruit abundantly over the summer months. A single plant can produce three or four fruits a week in good weather.¹ Two or three plants is typically enough to feed a whole family, with plenty left to share.²

Also known as zucchini, courgettes belong to the species Cucurbita pepo.¹ They fruit abundantly through summer and need surprisingly little skill to get started.

Choosing the Right Variety

Varieties come in many shades of green or yellow, with fruits either long or rounded.¹ Climbing types can be trained vertically up canes or wires, saving ground space.¹ Compact varieties work well in large containers or growing bags if you're short on space.¹

When and How to Sow Seeds

Sow seeds indoors in April or May, in pots of peat-free, multi-purpose compost.² Keep compost warm and moist, ideally in a propagator or covered tray at around 20°C.³ This gives seedlings a strong start before outdoor conditions are warm enough.

You can also sow directly outside in late May or early June for a later crop.² Prepare the soil by digging in plenty of compost or manure, and sow seeds about 2.5cm deep.³ Space them around 90cm apart to give each plant room to spread.³

Planting Out

Courgettes are tender plants, so wait until early summer before moving them outdoors.¹ Each plant needs roughly a square metre of ground.¹ Choose a warm, sunny, sheltered spot with rich soil.¹

Soil and Feeding

Rich soil is key. Dig in generous amounts of compost or well-rotted manure before planting.³ Courgettes are hungry plants and benefit from regular feeding through the growing season.

Watering

Water regularly, especially during dry spells.¹ Consistent moisture helps fruits develop evenly and prevents the plant from stressing.

Harvesting

You can pick courgettes at any size, but flavour and texture are best when fruits are small.¹ Regular harvesting encourages the plant to keep producing.¹ If left on the plant, fruits quickly swell into marrows.¹

The flowers are also edible and can be harvested too.¹

Common Problems to Watch

Poor fruit set is often caused by pollination failure. Courgettes rely on insects to transfer pollen between male and female flowers.

Powdery mildew can appear on leaves in late summer, especially in dry conditions. Keep plants well watered and spaced for good airflow to reduce the risk.

Growing in Pots

If garden space is limited, compact courgette varieties grow well in large containers.¹ Use a generous pot size and a rich compost mix. Water more frequently than you would in open ground, as pots dry out faster.

What to Watch Through the Season

Once plants are established and fruiting, the main jobs are watering regularly and harvesting to keep plants cropping.¹ Miss a few harvests and fruits will quickly swell into marrows.¹ Stay on top of picking and the plants will reward you all summer long.¹

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