How to Grow Courgettes at Home in the UK

Courgettes are probably the most satisfying crop a first-time grower can plant. Put two plants in the ground in late May, give them a sunny spot and generous watering, and by July you will be harvesting more courgettes than you know what to do with. The challenge is not getting them to grow — it is keeping up with them. This guide covers everything from choosing the right variety to managing the inevitable summer glut.

Why courgettes are worth growing

A single courgette plant can produce 20–30 fruits across a season. They grow fast — from planting out to first harvest takes around eight weeks — and they are genuinely low-maintenance once established. The plants are imposing too: large, architectural, with vivid yellow flowers and spreading leaves. Even if you only have a patio, a sufficiently large pot will support one productive plant all summer long.

Courgettes are also one of the few crops that actively reward beginners. Unlike tomatoes, they do not need pinching out or tying in. Unlike carrots, they are not fussy about soil texture. Unlike brassicas, the pests are manageable. The main skill you will develop is remembering to check under the leaves every two or three days — because a courgette that escapes your notice for a week becomes a marrow.

If you are just getting started with growing food, courgettes belong in your first season. You can read our guide to starting a vegetable garden for the broader picture, but for now: get two courgette plants in and enjoy the results.

Choosing a variety

Courgettes come in an impressive range of shapes, colours and sizes, and the UK seed market has excellent options at every level. Here are the varieties worth knowing about.

'Defender' F1 is the one to start with if you want a reliable, unfussy green courgette. It holds an RHS Award of Garden Merit, produces heavily, and has good resistance to cucumber mosaic virus — a common problem that causes mottled, distorted leaves. This is the variety you will find in most UK seed catalogues, and for good reason. Available from Suttons and Thompson & Morgan.

'Astia' F1 is a compact, patio-bred variety specifically developed for container growing. Where most courgette plants sprawl to fill a square metre of ground, 'Astia' stays bushy and upright, making it ideal for a large pot on a sunny patio. The fruit is standard green courgette, the yield is good, and it is well suited to growers with limited space.

'Orelia' F1 produces golden-yellow courgettes with a slightly sweeter, nuttier flavour than green varieties. It is striking in the garden — the contrast between the yellow fruit and the green-grey leaves is dramatic — and looks excellent on the plate. A good choice if you want something beyond the standard green, and it grows just as easily as 'Defender'.

'Cocozelle' is an Italian heritage variety with long, dark green fruit striped pale green. The flavour is excellent — more pronounced than modern F1 hybrids — and it crops steadily rather than in surges. Because it is an open-pollinated variety rather than an F1 hybrid, you can save seed from year to year. Available from Sarah Raven and specialist seed companies.

Round varieties such as 'Rond de Nice' and 'Eight Ball' produce ball-shaped fruits ideal for stuffing. Pick them when they are about the size of a tennis ball. They are novelty in one sense, but genuinely useful in the kitchen — a hollowed-out round courgette filled with rice and herbs is a different dish entirely from a sliced green courgette. They grow and care for exactly like standard varieties.

A note on marrows: a courgette left on the plant will eventually become a marrow — large, bulbous, and with a coarser texture. Most people prefer to harvest young (10–15cm), but if you miss one and it swells up, it is still edible. Stuffed marrow is a classic British dish. At the end of the season, letting one or two fruits mature fully and storing them in a cool, dry place means you can have marrows through to Christmas.

Where to grow courgettes

Sun is non-negotiable. Courgettes need a minimum of six hours of direct sun per day to produce well; in shade they sulk, produce few flowers, and are more susceptible to mildew. A south- or west-facing spot, sheltered from strong wind, is ideal. The large leaves act like sails and plants in exposed positions tend to rock and suffer.

Space. Each courgette plant needs roughly 1m² of ground — they are not a crop for a small corner of a raised bed. Two plants is usually enough for a family; three if you particularly love courgettes. If you plant four or more, be prepared to give produce away.

In containers: use the largest pot you can manage — at least 45–50cm wide and 40cm deep. A 50-litre fabric grow bag works very well; it drains freely, warms up quickly in the sun, and the fabric sides allow air to reach the roots. You can read more about container growing in our guide to growing food in containers. Choose a compact variety like 'Astia' if space is limited.

On a compost heap or mound: courgettes grow brilliantly planted directly into a well-composted mound of soil. The mound gives excellent drainage at the stem base (reducing rot) while the roots reach down into rich, moisture-retentive compost. If you have a spent compost heap, this is one of the best uses for it.

Soil preparation

Courgettes are hungry, thirsty plants and they need soil that reflects that. Poor soil equals poor fruit. Improving your soil before planting makes the difference between a plant that struggles and one that romps.

In a bed: dig in two or three generous spadefuls of well-rotted manure or garden compost per planting site in autumn or early spring, and allow it to settle. If you are preparing in spring, do it at least two or three weeks before planting to allow the soil to settle around the organic matter.

For a planting mound: mix roughly 50% compost with 50% garden soil to form a low, rounded mound about 30cm high and 60cm across. Plant the courgette at the top. The raised position keeps the stem base dry (reducing the risk of stem rot) while the compost feeds the roots below.

In containers: use a good-quality, peat-free multi-purpose compost. Mix slow-release fertiliser granules into the compost at planting — typically one generous tablespoon per pot — as container-grown plants cannot draw on the reserves in surrounding soil.

Sowing courgettes indoors

When to sow: late April to mid-May for most of the UK. This timing is important. Sow in early April and you will have large, pot-bound plants waiting weeks on a windowsill for the weather to warm up. Sow in mid-May and you will have well-sized transplants ready to go out at exactly the right moment. In Scotland and the north of England, mid-May sowings are particularly sensible — there is less time to recover from a cold snap, and fresh plants establish quickly.

How to sow: fill a 9cm pot with seed compost and make a hole 2cm deep. Place one seed on its edge (this reduces the risk of it rotting at the tip) and cover with compost. Water gently and cover the pot with a clear plastic bag or a propagator lid to retain warmth and moisture.

Temperature: courgette seeds germinate best at 20–25°C. A warm windowsill or a propagator is ideal. Do not put them on a cold north-facing sill — germination will be patchy and slow. Most seeds will be showing in five to seven days at the right temperature.

Once germinated: remove the cover immediately and move the seedling to the brightest spot you have. Courgette seedlings grow fast and become leggy very quickly without strong light. A greenhouse is ideal; a bright south-facing windowsill works well. Pot on into a 12–15cm pot if roots start showing at the drainage holes.

Direct outdoor sowing (late May onwards): once the last frost has passed and the soil has warmed, you can sow two seeds per station directly into prepared ground. Cover with a cloche or a cut-down plastic bottle for the first few weeks. Remove the weaker seedling once they are a few centimetres tall.

Planting out

Timing is everything here. Courgettes are completely frost-tender — a single frost, even a light one, will kill a young plant overnight. Use the frost date checker to find out when the last frost typically falls in your area.

As a general guide for the UK:

• Southern England and London: late May
• Midlands and East Anglia: early June
• Northern England and Wales: early to mid-June
• Scotland: mid-June onwards

Before planting out, you must harden off your seedlings. This means gradually acclimatising them to outdoor conditions over seven to ten days — taking them outside in the daytime and bringing them back in at night. Skipping hardening off and going straight from windowsill to garden is one of the most common causes of transplant failure.

How to plant: dig a hole large enough to comfortably take the rootball. Set the plant at soil level or slightly above — burying the stem too deeply encourages stem rot, particularly in wet summers. Firm the soil gently around the roots and water in generously. If the weather is still cool or windy, a cloche or fleece tent over the plant for the first week or two helps it establish.

Space plants at least 90cm apart. With two plants this usually means one at each end of a bed, or two sizeable containers on a patio.

Watering and feeding courgettes

Water is the most important ongoing job. A courgette plant in full production during a warm July can use the equivalent of a full watering can per day, and a container-grown plant may need watering twice a day in a heatwave. The symptoms of drought stress are wilting leaves in the afternoon, small or distorted fruit, and fruit rotting at the tip (blossom end rot).

How to water: always water at the base of the plant, not over the leaves. Wet foliage encourages powdery mildew, which is the most common problem with courgettes in a UK summer. Water deeply and thoroughly rather than a little every day — this encourages roots to grow down, making the plant more resilient in dry spells.

Feeding: for the first few weeks after planting, the compost you dug in or potted into provides enough nutrition. Once the first fruits begin to form — usually around six to eight weeks after planting — start feeding weekly with a liquid tomato feed (high in potassium). This encourages fruiting rather than leaf growth. Continue throughout the season until the plant starts to decline in late summer.

In containers, where the volume of compost is limited, begin feeding slightly earlier and continue more consistently. Container plants will also benefit from a foliar feed — a light spray of diluted liquid seaweed over the leaves — every two or three weeks.

Understanding flowers and pollination

Courgettes have two types of flowers on the same plant: male and female. The female flower has a tiny immature courgette at its base; the male flower sits on a plain stem. Early in the season, most plants produce only male flowers — this is normal. Female flowers follow, and once both are open at the same time, bees and other insects transfer pollen and the fruit begins to swell.

In a cool or wet summer, bee activity can be low and fruit set suffers. Growing pollinator-friendly plants nearby helps draw in the bees that do this work for you. If you are seeing plenty of flowers but few courgettes developing (the tiny ones at the base of female flowers turn yellow and drop off), hand-pollination is the solution. Use a small, clean paintbrush to transfer pollen from the centre of a male flower to the centre of an open female flower. Or simply snap off a male flower, peel back the petals, and press it gently against the open female. Do this in the morning when flowers are fully open.

Eating the flowers: both male and female flowers are edible and genuinely delicious. Male flowers (those without the tiny courgette) can be harvested freely without reducing your crop. Dip them in a light batter and fry in oil, or stuff them with a mixture of ricotta and herbs and bake briefly. Pick them in the morning while they are still open.

Harvesting courgettes

This is where most beginners go wrong — not through any gardening failure, but through not checking often enough.

Pick at 10–15cm. At this size the skin is tender, the seeds are barely formed, the texture is firm and the flavour is at its best. Let them grow to 25cm and they become watery and seedy. Let them reach 40cm and you have a marrow.

Check every two to three days. Courgettes can double in size overnight in warm weather. Get into the habit of lifting the large leaves and looking underneath, where courgettes often hide. A 10cm courgette on Monday can be a 25cm courgette by Wednesday.

Frequent picking stimulates more fruit. The plant's job is to set seed; once it has a large fruit developing, it reduces its investment in new flowers and fruit. Harvesting regularly keeps the plant producing.

At the end of the season, the plants deteriorate rapidly after the first autumn frost and are best composted. Leave one or two fruits on the plant to mature into full marrows if you want to store them — marrows keep in a cool, dry shed for several months.

Common problems with courgettes

Powdery mildew is the most common issue, appearing as a white, dusty coating on the upper surface of leaves, usually from August onwards. It rarely kills the plant but weakens it and reduces yield. It is almost impossible to avoid entirely, but consistent watering (drought stress accelerates mildew), good airflow around the plant, and choosing a resistant variety like 'Defender' will delay its onset. Once it arrives, remove the worst-affected leaves and continue picking. The plants will soldier on for several more weeks.

Blossom end rot (a soft, sunken brown patch at the fruit tip) is caused by inconsistent watering and the resulting calcium uptake failure. The fix is simple: water more regularly and do not let the plant dry out between waterings. It is not a disease and cannot spread between plants.

Poor fruit set in early summer is usually a pollination problem — either flowers are not yet both open at the same time, or bee activity is low. Hand-pollinate as described above. If neither male nor female flowers are present, the plant needs more warmth and sun.

Slug damage is most serious in the first two or three weeks after planting out, when seedlings are small. Protect with copper tape around containers, a ring of organic slug pellets (iron phosphate-based, safe for wildlife), or by setting beer traps nearby. Once the plant is established and growing strongly, slug damage becomes less significant.

Rotting stems at the base of the plant are usually caused by planting too deep or consistently wet conditions around the stem. There is no cure once the rot has set in; prevention means planting at or slightly above soil level and ensuring good drainage.

Leaves turning yellow beyond the usual late-season decline may indicate a magnesium deficiency, particularly in containers where nutrients are depleted over the season. A foliar spray of diluted Epsom salts (magnesium sulphate) — one teaspoon per litre of water — applied to the leaves can help.

What to do with a courgette glut

It happens to everyone. By mid-August you are checking under the leaves every morning and still finding courgettes the size of a small cricket bat. Here is how to deal with it.

In the kitchen: courgettes are far more versatile than their reputation suggests. Slice them into ribbons with a vegetable peeler and toss with pasta, olive oil, lemon and hard cheese — a true Italian preparation that is better than it sounds. Shred and combine with egg and flour to make courgette fritters, served with yoghurt and mint. Bake into a loaf of courgette and lemon cake (the moisture they add is extraordinary). Make a simple soup with courgette, potato, stock and a little cream. Hollow out round varieties and stuff with leftover rice and herbs.

Freezing: courgettes do not freeze well whole — they turn to mush when defrosted. But grated courgette freezes excellently. Grate surplus courgettes, squeeze out the excess moisture in a clean tea towel, pack into zip-lock bags in 200–250g portions, and freeze. Each bag is one batch of courgette bread, fritters, or soup. They will keep well for six months.

Giving away: do not underestimate the value of leaving a bag of courgettes on a neighbour's doorstep. Most people will be delighted; a few will have their own plants and will respond in kind with whatever they are growing. This is how gardening communities work.

Leave one to grow into a marrow: a fully grown marrow, harvested before the first frost and stored in a cool, dry shed, will keep until December. Stuff it, roast it alongside other vegetables, or use it in a curry. It is a different vegetable from a young courgette — denser, with a stronger flavour — and worth experiencing at least once.

Growing courgettes alongside other crops

Courgettes grow well near beans in the traditional "Three Sisters" combination (courgette, beans, sweetcorn), where the large leaves shade the soil, suppress weeds, and retain moisture. They can also be planted near tomatoes in a greenhouse or polytunnel, though both are large plants and both need space.

Avoid planting courgettes near other cucurbit crops (cucumbers, squash, pumpkins) if possible, as they share several pests and diseases. Spacing them around the garden rather than grouping them together reduces the risk of problems spreading.

If you have good garden soil to begin with, courgettes will reward you. If your soil is poor, invest in the compost before planting — it makes a visible difference.

The beginner's summary

Two plants, a sunny spot, generous compost, and the discipline to check under the leaves every couple of days. That is genuinely all you need for a summer's worth of courgettes. Start with 'Defender' F1 if you want reliability, 'Astia' if you are on a patio, or 'Orelia' if you want something with a little more colour.

Sow in late April or May, harden off carefully, plant after the last frost, water deeply and feed weekly once the fruit appears. The plants will do the rest. Your main job from July onwards is keeping up with the harvest — and deciding what to cook first.