Last Updated on: October 11, 2026

Growing Lettuce in December: How to Enjoy Fresh Salad Leaves Throughout Winter

December might not seem like the ideal month for growing lettuce, especially when temperatures are dropping, daylight hours are short and frost is becoming increasingly common across the UK. However, with the right varieties and a little protection, it is possible to continue growing and harvesting fresh lettuce throughout the colder months.

Growing lettuce in December is a brilliant way to keep your allotment, greenhouse or polytunnel productive when many other vegetables have finished for the season. Instead of leaving growing spaces empty until spring, you can make use of sheltered areas to produce fresh, homegrown salad leaves.

Here at Gardening with Ben, I always encourage gardeners to make the most of their growing spaces throughout the year. Winter gardening might be slower than summer gardening, but there is still plenty you can grow.

The important thing to remember is that lettuce grows much more slowly during December. Success often depends on sowing earlier in autumn, choosing suitable varieties and protecting established plants from harsh winter weather.

Can You Grow Lettuce in December in the UK?

Yes, you can grow lettuce in December in the UK, although growing conditions are very different from those in spring and summer.

Lettuce generally prefers cool conditions, which makes it suitable for autumn and winter growing. However, freezing temperatures, waterlogged compost and limited daylight can all affect its growth.

During December, the biggest challenge is often the lack of light rather than the cold alone.

When daylight levels become very low, lettuce growth can almost stop. This means that plants established during October or November are usually much more productive in December than seeds sown during the middle of winter.

For the best results, grow lettuce in:

• An unheated greenhouse
• A polytunnel
• A cold frame
• A sheltered raised bed with suitable protection
• Containers positioned somewhere bright and protected

Outdoor lettuce can survive in mild conditions, but a greenhouse or polytunnel usually provides more reliable winter harvesting.

Best Lettuce Varieties to Grow in December

Choosing the right lettuce variety makes a significant difference to winter growing success.

Not every lettuce is suitable for cold conditions, so look for varieties described as winter-hardy or suitable for autumn sowing.

1. Winter Density

Winter Density is a popular choice for growing lettuce during colder months.

It produces compact, upright heads with crisp leaves and is valued for its ability to tolerate cooler growing conditions.

It is particularly useful in greenhouses, polytunnels and protected outdoor beds.

2. Arctic King

Arctic King is a traditional winter lettuce variety known for its relatively good cold tolerance.

It produces soft green leaves and rounded heads.

Although it is hardy compared with many summer varieties, protection is still beneficial during severe frosts.

3. Valdor

Valdor is another winter lettuce variety worth considering.

It produces attractive green heads and is traditionally grown for harvesting during the cooler months.

It performs best when established before the shortest days of winter.

4. Winter Marvel

Winter Marvel is a traditional winter butterhead lettuce suitable for autumn sowing and overwintering.

Its tender leaves are ideal for salads and sandwiches.

Like other winter lettuces, it benefits from sheltered growing conditions.

5. Loose-Leaf Lettuce Varieties

Loose-leaf lettuce can also be useful for winter growing, provided you choose varieties suited to cooler conditions.

Rather than waiting for a complete lettuce head to develop, you can harvest individual outer leaves.

This makes loose-leaf lettuce particularly useful when growth is slow.

My advice: Try growing several different winter varieties rather than relying on just one. You can then discover which performs best in your particular greenhouse, polytunnel or garden.

Can You Sow Lettuce Seeds in December?

You can sow lettuce seeds in December, but germination and growth may be very slow.

For most UK gardeners, December is not the most productive month to start lettuce from seed in an unheated growing space.

If you already have established plants from autumn sowings, concentrate on looking after those first.

However, if you want to experiment with December sowing, there are a few ways to improve your chances.

How to Sow Lettuce Seeds in December

1. Fill seed trays or small pots with fresh, free-draining seed compost.
2. Water the compost lightly before sowing.
3. Sow the lettuce seeds thinly on the surface.
4. Cover with approximately 3–5 mm of fine compost, following the seed packet instructions.
5. Place the tray somewhere bright with a suitable germination temperature.
6. Keep the compost lightly moist rather than soaking wet.
7. Once seedlings appear, give them plenty of light to prevent weak, stretched growth.

Lettuce generally germinates well in cool to moderate temperatures, often around 10–20°C, depending on the variety.

Very warm conditions can actually reduce germination in some lettuce varieties.

A heated propagator is not normally essential, although gentle warmth can help when conditions are particularly cold.

If you germinate seeds indoors, move the seedlings into bright, cooler conditions after germination. A warm room with insufficient winter light can quickly produce weak plants.

Remember that seeds sown in December are more likely to provide useful harvests later in winter or early spring than during December itself.

Growing Lettuce in a Polytunnel During December

A polytunnel is one of the best places to grow winter lettuce.

It offers protection from heavy rain, cold winds and some frost while allowing natural daylight to reach the plants.

However, a polytunnel is not frost-free. Temperatures inside can still drop below freezing during particularly cold nights.

Preparing the Growing Area

Before planting winter lettuce, remove weeds and any remains of previous crops.

Loosen the soil gently if necessary, but avoid working it when it is saturated.

If your soil needs improving, incorporate a modest amount of mature compost before planting.

Lettuce grows best in fertile, moisture-retentive but well-drained soil.

Avoid adding large quantities of strong fertiliser during December because plants will not be growing quickly enough to use it efficiently.

Spacing Winter Lettuce

Spacing depends on the variety.

As a general guide:

• Small loose-leaf lettuce: approximately 15–20 cm apart
• Compact lettuce varieties: approximately 20–25 cm apart
• Larger heading lettuce: approximately 25–30 cm apart

Check the seed packet for the recommended spacing.

Good airflow between plants is especially important during winter because damp, stagnant conditions can encourage fungal diseases.

Growing Lettuce in Containers During Winter

You do not need a large garden or allotment to grow lettuce in December.

Containers can work particularly well, especially if you have a greenhouse, sheltered patio or bright cold frame.

Choose a container with drainage holes and fill it with good-quality multipurpose compost.

For loose-leaf lettuce, a container around 15–20 cm deep is generally sufficient.

Larger lettuce varieties benefit from additional space.

Position containers where they receive as much natural daylight as possible.

One advantage of container growing is that pots can be moved into a more sheltered position when particularly cold weather is forecast.

However, compost in containers can freeze more quickly than soil in the ground, so extra insulation may be needed during severe frost.

Avoid standing pots permanently in trays of water during winter.

Protecting Lettuce from Frost in December

Although winter lettuce varieties can tolerate cold conditions, prolonged freezing temperatures may damage their leaves.

Protection is particularly important for young plants.

Use Horticultural Fleece

Horticultural fleece provides an additional layer of protection during cold nights.

It can be placed over hoops to create a small tunnel above your lettuce.

Keeping the fleece slightly raised helps prevent it from resting directly on the leaves.

Remove or adjust coverings when conditions improve so plants receive sufficient light and ventilation.

Use a Cold Frame

Cold frames are excellent for growing winter salad crops.

They protect lettuce from wind and excessive rainfall while allowing natural daylight inside.

Remember to ventilate cold frames during mild, sunny weather to prevent condensation and overheating.

Add Extra Protection Inside a Polytunnel

During severe frost, you can create a smaller protected growing area inside your polytunnel using hoops and fleece.

This double layer of protection can help reduce exposure to freezing conditions.

However, fleece does not provide unlimited protection. Very severe or prolonged cold can still damage lettuce.

How Often Should You Water Lettuce in December?

One of the biggest mistakes gardeners make during winter is watering too frequently.

Lettuce requires moisture, but it uses much less water during December because growth is slow and evaporation is reduced.

Before watering, check the compost or soil beneath the surface.

If it still feels moist, there is usually no need to add more water.

When watering is necessary, apply water directly to the soil around the plants.

Try to water earlier in the day so excess moisture has time to drain away before temperatures fall overnight.

Avoid repeatedly soaking the leaves, particularly in enclosed greenhouses and polytunnels.

Waterlogged conditions can encourage root problems and increase the risk of rotting.

Common Problems When Growing Winter Lettuce

Even with protection, winter lettuce can experience a few difficulties.

Slugs and Snails

Slugs can remain active during mild winter weather, particularly inside protected growing spaces.

Inspect plants regularly and remove hiding places such as old pots, weeds and discarded plant material.

Grey Mould

Grey mould can develop in damp, poorly ventilated conditions.

Remove damaged or decaying leaves promptly and avoid overcrowding.

Ventilate your greenhouse or polytunnel whenever weather conditions allow.

Yellowing Leaves

Yellow leaves may be caused by natural ageing, excessive moisture, poor drainage or low light.

Remove badly damaged leaves and check that the soil is not constantly wet.

Slow Growth

Slow growth is normal during December.

The combination of low temperatures and short days means lettuce may produce very little new growth for several weeks.

Avoid trying to force growth with excessive feeding or watering.

Patience is often the most important part of successful winter lettuce growing.

How to Harvest Lettuce in December

Harvesting winter lettuce requires a slightly different approach from summer harvesting.

Because plants grow slowly, avoid removing too many leaves at once.

For loose-leaf varieties, pick a few mature outer leaves from each plant while leaving the central growing point intact.

This allows the plant to continue producing new leaves when conditions improve.

For heading varieties, harvest the entire head when it reaches a suitable size.

Always check leaves for frost damage, pests or signs of decay before bringing them indoors.

If lettuce leaves are frozen, allow them to thaw naturally before handling them. Frozen leaves are easily bruised and damaged.

Freshly harvested winter lettuce is ideal for sandwiches, salads and adding a little homegrown produce to meals during the colder months.

Planning Ahead for Better Winter Lettuce Harvests

If you want a reliable supply of lettuce during December, preparation should begin much earlier in the year.

For many UK gardeners, late summer and early autumn are the most useful times to sow winter lettuce.

Sowing in August, September or early October, depending on the variety and growing conditions, gives plants time to establish before winter.

The aim is to have healthy, reasonably mature plants ready when daylight levels begin to fall.

You can also make several small sowings rather than planting everything at once.

This spreads the harvest and reduces the risk of losing your entire crop to one spell of poor weather.

Keep notes about which varieties perform best in your growing space.

After a few seasons, you will have a much better idea of the best sowing dates for your own allotment or garden.

Frequently Asked Questions About Growing Lettuce in December

Will lettuce survive frost?

Some winter-hardy lettuce varieties can survive light frosts, particularly when established and protected. Severe or prolonged freezing weather can still cause damage.

Can I grow lettuce in an unheated greenhouse?

Yes. An unheated greenhouse is a useful place for winter lettuce, especially when plants were established during autumn. Extra frost protection may be necessary.

How long does lettuce take to grow in December?

Growth is highly dependent on temperature and daylight. Lettuce sown during December may take considerably longer to reach harvesting size than lettuce sown in spring.

Should I feed winter lettuce?

Established winter lettuce usually requires very little additional feeding. If the soil or compost is reasonably fertile, avoid unnecessary fertiliser during periods of slow growth.

Can I grow lettuce on a windowsill?

You can start lettuce seedlings on a bright windowsill, but winter light levels may be insufficient for strong growth. A suitable grow light can help if you are growing indoors.

Final Thoughts from Gardening with Ben

Growing lettuce in December is a great way to continue enjoying homegrown produce during the colder months.

Although growth is slower and plants need a little more protection, winter lettuce can be a worthwhile crop for gardeners with a greenhouse, polytunnel, cold frame or sheltered growing space.

The key is to choose suitable winter varieties, establish plants before the darkest weeks of the year, avoid overwatering and protect crops when severe frost is forecast.

Even a small harvest of fresh lettuce leaves during winter can be incredibly satisfying.

And remember, you do not need to stop gardening just because December has arrived. There are still plenty of opportunities to grow something throughout the winter.

Keep smiling, keep shining, keep gardening with Ben!