How to Grow Pumpkins and Squash in the UK

Pumpkins and squash are some of the most satisfying crops you can grow. Each plant gives you a few big, impressive fruits by late summer. They come in all sorts of shapes, from flat discs to tall turbans, and colours from cream to orange to blue-grey.

UK gardens suit them well. All they need is a long, frost-free summer, rich soil and plenty of sun. Here’s everything from sowing seeds indoors in April to curing and storing squash well into the next spring. The method is the same for carving pumpkins and nutty roasting squash.

Understanding pumpkins, summer squash, and winter squash

Summer squash is eaten young, winter squash is left to ripen and stored, and pumpkins are a type of winter squash. They’re all part of the same family.

Summer squash has thin, edible skin and soft flesh. You pick it young and eat it within days. Courgettes, Patty Pan and Crookneck are all summer squash. They crop quickly, within a couple of months of planting out, and keep coming if you pick often.

Winter squash has a hard skin and dense flesh. You leave it on the plant until fully ripe, cure it in the sun and store it for months. Butternut, Crown Prince, Uchiki Kuri and spaghetti squash are all winter squash. They need a long, frost-free summer.

Pumpkins are really just winter squash with a familiar name. Jack O’Lantern, Rouge Vif d’Etampes and Atlantic Giant are grown, cured and stored the same way.

Choosing varieties for UK gardens

Pick varieties that ripen in about 100-120 days, such as Crown Prince, Uchiki Kuri and Jack O’Lantern. UK summers aren’t as long and hot as American ones, so quicker varieties are safer.

Pumpkin varieties

• Jack O’Lantern, the classic orange carving pumpkin. Grows well in southern and central England.
• Rouge Vif d’Etampes, a flat, deeply ribbed French heirloom with orange-red skin. Lovely for cooking and display.
• Small Sugar (also called New England Pie), a compact pumpkin grown for cooking rather than carving, with sweet, dense flesh. Reliable here.
• Baby Bear, with small pumpkins on a short season. Great for children and small spaces.

Winter squash varieties

• Crown Prince, with blue-grey skin, bright orange flesh and a wonderful flavour. One of the best all-round winter squash for UK gardens, and it keeps for months.
• Uchiki Kuri (red kuri), onion-shaped and bright orange, with a sweet, chestnut-like taste. It ripens early.
• Butternut (Waltham or Hunter), the classic pear-shaped squash. Needs a warm, sheltered spot here. Hunter suits shorter summers.
• Spaghetti squash, pale yellow and oval. The cooked flesh pulls apart into strands, which children love.

Summer squash varieties

• Patty Pan (Sunburst), scallop-shaped and bright yellow. Pick at 7-8cm across for the best taste. Crops heavily.
• Tromboncino, an Italian climber with long, curly fruits. It grows upwards, saving space. Pick young, or leave some to harden like a winter squash.

Variety comparison table

Gardener’s tip: Crown Prince and Uchiki Kuri are two of the most reliable winter squash for UK gardens. If you only grow two, make it these.

How to sow pumpkin and squash seeds indoors

Start seeds indoors in mid to late April, about 4 weeks before you plan to plant out. New to seed sowing? Our guide to sowing seeds indoors covers the basics.

Sowing method

1. Fill 9cm pots with seed compost. Water and let them drain.
2. Push each seed in on its edge, not flat, about 2cm deep. That stops water sitting on the seed and rotting it.
3. Cover with a thin layer of compost or vermiculite.
4. Keep in a propagator or on a warm windowsill at 18-20°C.
5. Seeds usually come up in about a week. Move them to a bright windowsill once they do.
6. Keep the compost moist but not soggy. Too much water kills more squash seedlings than too little.

Sow two seeds per pot and remove the weaker one once they’re up. Don’t sow outdoors in the UK. The soil is too cold in April, and May is too late for a good crop.

Pushing each seed in on its edge stops water sitting on it and rotting it. Cover with a thin layer of compost and keep it warm.

Hardening off

Start hardening off in mid-May. Put the plants outside during the day and bring them in at night for 10-14 days. By late May they should be ready to go out for good, once the last frost has passed.

Planting out and growing on

Plant out only after the last frost. In southern England that’s usually late May. In northern England and Scotland, wait until early June. Check the frost dates for your area.

Preparing the planting site

Pumpkins and squash are hungry and thirsty. Give them the richest soil you can.

1. Dig a hole about 30cm deep and wide for each plant.
2. Fill it with well-rotted manure or garden compost mixed with the soil you dug out. Our composting guide shows how to make your own.
3. Pile it into a mound 10-15cm higher than the soil around it. This helps drainage and warms the roots.
4. Space trailing varieties 1.5-2m apart and bush types 1m apart.

A rich mound feeds these hungry plants and warms the roots. Space trailing types 1.5-2m apart so they have room to roam.

Planting technique

Water the plant well first. Dig a hole in the middle of the mound just big enough for the root ball and plant at the same depth as in the pot. Water in well. If nights are still chilly, cover with a cloche or fleece for the first couple of weeks.

Watering and feeding

Water deeply twice a week in dry weather. Water the base of the plant, not the leaves, as wet leaves encourage powdery mildew.

Feed weekly with a high-potash feed such as tomato food once the first flowers appear. It boosts flowers and fruit. A high-nitrogen feed gives big leaves but fewer fruits.

Hand pollination for a reliable fruit set

Squash have separate male and female flowers on the same plant. Males appear first, on long thin stalks. Females follow a week or two later. You can spot a female by the little round swelling, the baby fruit, just behind the petals.

In a warm garden full of bees, pollination happens on its own. In a cool, wet summer, bees are less busy and fewer fruits set. Hand pollinating is easy and really helps.

The female flower on the left has a baby fruit behind the petals, while the male sits on a long thin stalk. Dab pollen from the male into the female’s centre in the morning.

How to hand pollinate

1. Do it in the morning, when the flowers are freshly open.
2. Pick a male flower and peel back the petals to show the pollen-covered centre.
3. Dab the pollen gently onto the centre of a female flower. A soft paintbrush works too.
4. One male flower can pollinate 2-3 females.

If a young fruit starts to swell, then shrivels and drops, poor pollination is almost always why. Hand pollinate every female flower you see in June and July.

Why does my squash plant only have male flowers?

Male flowers always come first, often a week or two before any females. A young plant full of male flowers is perfectly normal, so give it time.

If there are still no females by mid-July, the usual causes are cold nights, too little sun or too much nitrogen. A rich manure mound plus a general feed can push leaves instead of flowers, so switch to tomato feed. Many trailing varieties carry more female flowers on side shoots, so pinch out the main tip once it reaches about 1m. Dry roots also mean fewer flowers, so keep watering steady.

Month-by-month growing calendar

This calendar suits central England. In the south, move everything a week earlier. In Scotland and northern England, move it a week or two later.

Gardener’s tip: For bigger pumpkins, keep just 2-3 fruits per plant. Once they’re golf-ball sized, remove any new female flowers so the plant puts its energy into the ones you’ve chosen.

Common problems and how to fix them

Powdery mildew

White, dusty patches on the leaves are almost certain by late summer. It’s the most common squash problem in the UK. It weakens the plant but rarely kills it.

Prevention: Space plants well so air can move. Water the soil, never the leaves. The RHS powdery mildew guide notes that plants short of water are more likely to get it, so water regularly in dry spells. Choose resistant varieties where you can.

Treatment: Remove the worst leaves to slow it down. Home-made milk sprays aren’t approved for use in the UK, so don’t use them. If you want to spray, use only a product approved for home use on edible crops, exactly as the label says.

Some mildew is almost certain by late summer. Water the soil rather than the leaves, and plants short of water get it worse.

Fruit rot

Fruits sitting on damp soil rot underneath. Put a roof tile, slate or thick pad of straw under every developing fruit to lift it off the wet ground.

Poor fruit set

If flowers drop without forming fruit, the usual reason is poor pollination. Hand pollinate every female flower. Cold, wet weather in June and July means fewer bees. Growing bee-friendly plants nearby helps bring them in.

Slugs and snails

Young plants are at risk. Protect them for the first few weeks with copper tape, beer traps or ferric phosphate slug pellets used as the label directs. Once plants are established, the stems toughen up and slugs do less damage.

Small or few fruits

This usually means too little food or water. Squash are among the hungriest crops in the garden. They need a rich compost base, weekly feeding and steady moisture. Crowding cuts the crop too, so stick to 1.5-2m spacing.

Common mistakes to avoid

Pumpkins and squash are easy, but these slip-ups cost people their harvest every year.

1. Sowing too early. Seeds sown in March are leggy and overgrown by late May. Mid-April is soon enough.
2. Planting out before the last frost. One frost kills squash outright. Wait until late May in the south and early June in the north. Keep fleece handy.
3. Sowing seeds flat. Seeds rot if water sits on them. Always sow on their edge.
4. Not feeding enough. These are greedy plants. Without weekly tomato feed from first flowering, crops drop.
5. Watering the leaves. Wet leaves invite mildew. Always water at the base.
6. Picking too early. Winter squash must be fully ripe. The skin should be too hard to dent with a thumbnail, and the stalk dry and corky.
7. Skipping curing. Uncured squash rots within weeks. Curing in the sun for 10-14 days makes it last much longer.
8. Leaving fruit on bare soil. Heavy fruit on the ground rots, and unsupported fruit on a trellis snaps off. Use straw, tiles or slings.

Curing and storing winter squash

Cure winter squash in the sun for 10-14 days, then store it in a dry room at 10-15°C. Curing turns a squash that would keep for weeks into one that keeps for months.

How do you know when a pumpkin is ready to harvest?

A pumpkin is ripe when the skin is hard and the colour is deep and even. The stalk will also start to dry and crack. A ripe fruit sounds hollow when you tap it.

Press a thumbnail into the skin away from the stalk. If it leaves no mark, the fruit is ripe. The leaves often die back at the same time. In most of the UK this happens from mid-September into October.

Leave fruit on the plant as long as you can, but bring it in before the first frost. The RHS pumpkin guide points out that frosted pumpkins won’t store. If a cold night is forecast before they’re ripe, cover them with fleece or straw.

Leave about 10cm of stalk when you cut, and never carry a pumpkin by it. A ripe skin won’t dent when you press it with a thumbnail.

How to cure

1. Harvest in September, before the first frost. Cut with a sharp knife, leaving 10cm of stalk. Never carry pumpkins by the stalk.
2. Set them in full sun for 10-14 days. A south-facing patio or greenhouse bench is perfect.
3. If rain is forecast, move them under cover somewhere airy. A cold frame with the lid propped open works well.
4. They’re cured when the skin is hard, the colour has deepened and the stalk is dry and corky.

Ten to fourteen days in the sun hardens the skin so squash keeps for months. They’re done when the stalk is dry and corky.

Storage conditions

Store cured squash in a cool, dry room at 10-15°C. A spare bedroom, utility room or unheated porch is ideal. A cold garage or shed is too chilly, and damp cellars cause rot.

Lay them on slatted shelves or in single layers on newspaper, without stacking. Check them every month and use any with soft spots first.

Expected storage times

Well-cured Crown Prince kept in a cool, dry room can last into March. That’s months of home-grown dinners from a seed sown in April.

When should you sow pumpkins for Halloween?

For carving on 31 October, sow indoors in late April or early May and plant out in late May or early June. Carving varieties such as Jack O’Lantern need around 100-110 days to colour up.

Pumpkins sown then usually ripen from late September. Harvest before the first frost, cure for 10-14 days and keep them whole somewhere cool and dry until Halloween. A cured, uncut pumpkin keeps for several weeks.

Don’t carve too early. Once cut, a pumpkin goes soft and mouldy within days, faster in a warm house. Carve no more than two or three days before Halloween. Carving pumpkins are edible but watery and stringy, so use a squash like Crown Prince for soup.

Growing pumpkins and squash in small spaces

You don’t need a big plot. You can grow squash in small gardens, raised beds and even on a patio.

Bush varieties like Table Gold, Honey Bear and Patty Pan need only about 1m per plant and don’t send out long trailing stems.

Growing up works for lighter varieties. Train Tromboncino, Small Sugar or Uchiki Kuri up a strong trellis, arch or fence. Hold the fruits in mesh bags or old tights tied to the frame.

Pots work for bush types. Use a pot or grow bag of at least 45 litres with drainage holes, filled with half multipurpose compost and half well-rotted manure. Water daily in hot weather and feed twice a week with tomato food.

If you’re planning a new growing area, our guide to starting a vegetable garden covers choosing a spot, preparing the soil and laying it out. Late May is also a busy planting time for lots of other crops in our what to plant in May guide.

Now you know how to grow pumpkins and squash, read our guide on starting a vegetable garden in the UK to plan where these space-hungry plants fit on your plot.

Lighter squash like Tromboncino can go up instead of out. Hold heavier fruits in mesh slings tied to the frame so they don’t snap off.

Frequently asked questions

When should I sow pumpkin seeds in the UK?

Sow pumpkin seeds indoors in mid to late April. Push them in on their edge in 9cm pots of seed compost, somewhere warm at 18-20°C. They come up in about a week. Plant out after the last frost, usually late May in the south and early June in the north.

How much space do pumpkins need?

Give each plant 1.5-2m of space all round. Giant trailing types like Atlantic Giant need 3m or more. Bush varieties such as Table Gold need only about 1m. Plant on a mound of compost to help drainage and warmth.

What is the difference between summer and winter squash?

Summer squash is picked young and eaten fresh. It has soft, edible skin and crops within weeks of planting. Winter squash has a hard skin, ripens on the plant over a long summer and stores for months. Courgettes are summer squash, while butternut and Crown Prince are winter squash.

Do I need to hand pollinate pumpkins?

It helps, especially in cool or wet summers. Bees are less busy then, so fewer fruits set. In the morning, pick a male flower, peel back the petals and dab the pollen onto the centre of a female flower. Female flowers have a small swelling behind the petals.

How do I cure pumpkins for storage?

Leave them in full sun for 10-14 days to harden the skin. If rain is forecast, move them under cover somewhere airy. They’re ready when your thumbnail can’t dent the skin. Cured squash keeps for months.

Why are my pumpkin fruits rotting before they ripen?

Usually because they’re sitting on damp soil. Slip a tile, slate or pad of straw under each fruit to lift it up. Poor pollination also makes small fruits shrivel and drop. Too much water in late summer adds to the risk.

Can I grow pumpkins in a small garden?

Yes, choose a compact bush variety like Table Gold or Honey Bear. These need only about 1m of space. Train trailing types up a strong trellis or arch, with heavy fruit held in mesh slings. A pot of at least 45 litres suits one bush plant.