Greenhouse vs Outdoor Cucumbers: Which to Grow

The short answer is simple: if you have a greenhouse or polytunnel, grow greenhouse cucumbers for long, smooth, heavy crops. If you don't — or you just want the easiest possible life — grow outdoor ridge cucumbers in a warm, sheltered spot. They're two genuinely different plants bred for different conditions, and picking the right one for your situation matters far more than the variety name on the packet.

This is a quick honest comparison to help you choose. For the full sowing-to-harvest method, see the main how to grow cucumbers guide.

The quick verdict

• Have a greenhouse, polytunnel or conservatory? Grow greenhouse cucumbers. Longer, smoother, almost seedless fruit and bigger overall yields.
• No greenhouse — just a garden, patio or grow bag outdoors? Grow outdoor (ridge) cucumbers. Tougher, more forgiving and perfectly tasty.
• Total beginner, want a near-guaranteed crop? Start with outdoor ridge types. They are the more relaxed plant by a clear margin.

Everything below explains why.

Greenhouse (indoor) cucumbers — the pros and cons

Greenhouse cucumbers are the classic supermarket-style fruit: long, dark green, smooth-skinned and almost seedless. Grown under cover, a healthy plant can produce a steady flush of cucumbers from midsummer well into autumn, and a couple of plants will keep most households more than supplied.

The yield and quality are the real draw. With the warmth and shelter of a greenhouse, indoor types crop heavily and the fruit is long, thin-skinned and never bitter. If you already grow under glass — see our guide to greenhouse growing — cucumbers are one of the most rewarding things you can put in there alongside tomatoes.

The catch is the conditions they need. Greenhouse cucumbers want warmth (ideally 18–25°C), high humidity and shelter from wind. Outdoors in a typical UK summer they sulk, check growth in cold snaps and rarely thrive — which is exactly why they're a poor choice without cover. They also need a bit more attention: tying in to canes or strings, generous watering and regular feeding once fruiting.

Most are all-female — and that matters

Modern greenhouse varieties are usually all-female F1 hybrids such as 'Carmen', 'Bella' and 'Femspot'. All-female plants are bred to set fruit without pollination, which is the whole point indoors where bees are scarce.

Here's the bit beginners trip over: if an all-female plant is accidentally pollinated, the fruit turns bitter and fat with hard seeds. So with traditional greenhouse types you should pinch off any male flowers that appear. The easy way to tell them apart — female flowers have a tiny cucumber-shaped swelling behind the petals; males sit on a plain thin stalk with nothing behind them.

For the full method — sowing dates, training up strings, watering and feeding under glass — see our dedicated greenhouse cucumbers guide.

Greenhouse cucumbers in short:

• ✅ Long, smooth, almost seedless fruit
• ✅ Heavy, reliable crops over a long season
• ✅ No pollinators needed (all-female types)
• ❌ Need a greenhouse, polytunnel or similar warm shelter
• ❌ More watering, feeding and tying-in
• ❌ Must remove male flowers on some varieties to avoid bitterness

Outdoor (ridge) cucumbers — the pros and cons

Outdoor cucumbers are usually called ridge cucumbers, a nod to the old practice of growing them on raised ridges of warm soil. They tend to be shorter, stubbier and often a little knobbly or rough-skinned compared with their greenhouse cousins — but flavour-wise they're excellent, with a fresh, slightly sweeter crunch.

Their great virtue is toughness. Ridge cucumbers are bred to cope with British weather: cooler nights, the odd grey week and a bit of breeze. You can grow them in the open ground, in a raised bed, in a large pot or a grow bag on a sunny patio — no greenhouse required. That makes them the obvious starting point for anyone without cover, and the most forgiving choice for a first try.

They are also genuinely lower-maintenance. Many ridge varieties scramble happily along the ground or up a simple wigwam of canes with minimal training, and they shrug off neglect that would stop a greenhouse plant in its tracks.

These ones DO want pollinators

The key difference: most ridge cucumbers carry both male and female flowers and need insects to move pollen between them, so don't remove the males — you need them. A garden that welcomes bees and hoverflies will set fruit far better, so it's worth growing a few pollinator-friendly plants nearby. Good UK outdoor varieties to look for include 'Marketmore', 'Burpless Tasty Green' and the round, pale 'Crystal Apple'.

The trade-offs are real but modest. Crops are usually a little smaller and the season slightly shorter than under glass, and a genuinely cold, wet summer can hold them back. But for a garden-grown salad cucumber with no special kit, they're hard to beat — and you can grow them in containers too, as in our cucumbers in pots guide.

Outdoor ridge cucumbers in short:

• ✅ No greenhouse needed — garden, bed, pot or grow bag
• ✅ Tougher and far more beginner-friendly
• ✅ Less training, watering and fuss
• ✅ Great fresh flavour
• ❌ Shorter, sometimes knobbly fruit with more seeds
• ❌ Need bees and hoverflies to pollinate
• ❌ Smaller crops and a slightly shorter UK season

A quick chooser by situation

Not sure which way to go? Match your situation to the row below.

There's no shame in growing both if you have the room: a greenhouse plant for the long slicing cucumbers and a ridge plant outside as a tough backup. Many UK gardeners do exactly that.

What next

Whichever type you pick, the basics — warm sowing in spring, rich moisture-holding soil, steady watering and feeding once fruiting starts — are much the same. Get those right and cucumbers are one of the most generous crops you can grow.

Ready to sow? Head back to the full how to grow cucumbers guide for sowing dates, spacing and care, or browse more crops over on the grow vegetables hub. If bitter fruit ever crops up, our note on why cucumbers turn bitter explains the usual causes and how to avoid them.