How to Grow Courgettes in the UK: Complete Growing Guide
Courgettes (zucchini) are prolific, easy-to-grow vegetables that thrive in the UK climate. With their vigorous growth and abundant harvests, a few plants can keep you supplied with fresh courgettes throughout summer.
Not sure when to sow? See our When to Plant Courgettes UK →
Founder & Head Grower, SoilCommander · RHS Level 2 · 12+ years growing in Yorkshire
I've been growing vegetables on my Yorkshire allotment and raised beds since 2012. Everything I write is based on what I've actually grown, failed at, and eventually got right in a real UK climate.
Watch our step-by-step guide to growing courgettes in the UK — from sowing seeds indoors to harvesting a bumper crop all summer long.
🌱 Did you know? A single courgette plant can produce up to 30 fruits in one season if harvested regularly!
Quick Growing Facts
- Sowing Time: April to May indoors; May to June outdoors
- Harvest Time: July to October
- Growing Time: 8-12 weeks from sowing to first harvest
- Difficulty: Easy
- Position: Full sun, sheltered
When to Sow Courgettes
- Indoor sowing: April-May in pots or modules for transplanting after last frost
- Outdoor sowing: Late May-June when soil has warmed and frost risk has passed
- Transplanting: Plant out in late May-early June after hardening off
- Succession sowing: Sow 2-3 times at 2-week intervals for extended harvest
Soil Preparation
- Soil type: Rich, moisture-retentive but well-drained soil
- Add organic matter: Dig in plenty of well-rotted manure or compost
- Create planting pockets: Dig holes 30cm (12 inches) deep and wide, fill with compost
- pH level: Slightly acidic to neutral (pH 6.0-7.0)
- Warm soil: Ensure soil temperature is at least 12°C before planting out
How to Sow Courgettes
Indoor Sowing (recommended for UK):
- Use large pots: Sow in 7.5cm (3 inch) pots or modules filled with seed compost
- Sow on edge: Push seeds 2.5cm (1 inch) deep on their edge to prevent rotting
- One seed per pot: Sow one seed per pot as germination rates are high
- Warmth needed: Keep at 20-25°C for germination (7-10 days)
- Good light: Move to bright, frost-free location once germinated
- Pot on if needed: Transfer to larger pots if plants outgrow modules before planting out
Direct Outdoor Sowing:
- Only suitable for late May-June in warm, sheltered locations
- Sow 2-3 seeds per station, 90cm (3 feet) apart
- Thin to strongest seedling once established
- Protect with cloches or fleece until established
💡 Top Tip
Courgettes don't like root disturbance. Sow in biodegradable pots that can be planted directly into the ground, or use large modules and transplant carefully with the entire root ball intact.
Planting Out
- Harden off: Acclimatise plants to outdoor conditions over 7-10 days
- After last frost: Plant out only when all frost risk has passed (late May-early June)
- Spacing: Space plants 90cm (3 feet) apart in all directions
- Plant level: Plant at the same depth as in the pot
- Water well: Water thoroughly after planting
- Protect initially: Use cloches or fleece for first few weeks if weather is cool
Ongoing Care
- Watering: Water generously and regularly, especially when flowering and fruiting; aim for 20 litres per plant per week in dry weather
- Feeding: Feed weekly with high-potash liquid fertiliser once flowering begins
- Mulching: Apply thick mulch around plants to retain moisture and suppress weeds
- Weeding: Keep weed-free, but be careful not to damage shallow roots
- Support fruits: Place a tile or board under fruits to prevent rotting on damp soil
Common Problems
Poor fruit set: Often due to lack of pollinating insects. Hand-pollinate by transferring pollen from male flowers (thin stem) to female flowers (swollen base) using a soft brush.
Powdery mildew: White powdery coating on leaves. Ensure good air circulation, water at base of plants, and remove affected leaves.
Rotting fruits: Caused by contact with damp soil or poor pollination. Raise fruits off ground and ensure proper pollination.
Slugs and snails: Can damage young plants. Protect with barriers, traps, or organic pellets.
Harvesting Courgettes
- Timing: First harvest usually 8-12 weeks after sowing
- Size: Harvest when 10-15cm (4-6 inches) long for best flavour and texture — the RHS notes that letting fruit oversize signals the plant to stop producing, cutting your total yield
- Pick regularly: Check plants every 2-3 days and harvest all ready fruits
- Cut cleanly: Use a sharp knife to cut fruits with a short stem attached
- Don't let them grow large: Large courgettes (marrows) reduce plant productivity
- Flowers edible: Male flowers can be harvested and eaten (stuffed and fried)
Storage
- Fresh: Store in the refrigerator for up to 1 week
- Don't wash: Store unwashed; wash just before use
- Freezing: Slice, blanch for 1 minute, cool, then freeze for up to 6 months
- Preserving: Pickle, make into chutney, or dry in a dehydrator
Recommended Varieties
- Defender: F1 hybrid, high yields, good disease resistance
- Black Beauty: Classic dark green variety, reliable and productive
- Romanesco: Italian ribbed variety with excellent flavour
- Gold Rush: Bright yellow fruits, attractive and tasty
- Tromboncino: Climbing variety, long curved fruits, good for small spaces
- Patio Star: Compact variety ideal for containers
Essential Tools & Supplies
Plan Your Vegetable Garden
Get our comprehensive UK Vegetable Garden Planner PDF to plan your entire growing season.
Get the Planner — £19 →Tools That Help With This Crop
Use these links when the guide moves from reading into sowing, planting, watering, and keeping the crop healthy.
Plan the next step
Use the printable UK Vegetable Garden Planner to turn this guide into sowing dates, bed layouts, and weekly garden tasks.