Growing Lettuce in December: Tips and Advice for a Winter Harvest

As winter sets in, many gardeners start to wind down their gardening activities, assuming that the colder months mean a halt to productive growing. However, with the right strategies and a little preparation, you can keep your garden producing delicious crops even in the middle of winter. One versatile and resilient crop to consider during this season is lettuce.

Lettuce is a cool-weather crop that can thrive even in the colder months, making it an ideal choice for planting in December. With proper care and the right varieties, you can enjoy fresh, homegrown lettuce through winter and into early spring. In this guide, we’ll walk you through everything you need to know about planting and growing lettuce in December, including tips on soil preparation, protection from frost, and how to maintain your lettuce crop during winter.

Why Grow Lettuce in December?

Lettuce is a hardy, cool-season vegetable that can tolerate lower temperatures and is perfect for growing when many other crops can’t handle the cold. While winter can be a challenging time for many plants, lettuce thrives in cooler weather, making it an excellent option for winter gardens.

December offers a perfect opportunity to plant lettuce, either in a greenhouse, polytunnel, or using protective methods in the garden. By planting in December, you set the stage for a winter harvest and keep your garden productive during the colder months.

The Benefits of Growing Lettuce in December:

Cold Tolerance: Many lettuce varieties can withstand frost and even light snow, making them ideal for winter growing.
Quick Growth: Lettuce is a fast-growing crop, which means you can plant it in December and still enjoy fresh greens within weeks.
Continuous Harvest: By planting lettuce in succession, you can enjoy a continuous supply of fresh leaves throughout the winter.
Space Saver: Lettuce doesn’t require a lot of space, so it’s perfect for small garden beds, raised beds, or even containers indoors.

Choosing the Right Lettuce Varieties for December

While lettuce is generally cold-tolerant, some varieties are better suited for winter growing than others. When selecting lettuce varieties for December, look for those specifically bred for cold weather and frost resistance.

Here are some excellent options for growing lettuce in winter:

Winter Lettuce Varieties:

Winter Gem: This variety is a popular choice for winter gardening. Winter Gem is compact and produces crisp, sweet leaves even in colder temperatures.
Arctic King: As the name suggests, Arctic King is well-suited to winter conditions and can withstand frosty weather. It produces large, dark green heads with tender leaves.
Merveille des Quatre Saisons: A beautiful butterhead lettuce with red-tinged leaves that performs well in cooler weather, making it perfect for December sowing.
Valdor: A hardy lettuce variety that is ideal for growing under cloches or in cold frames, Valdor produces sweet, crunchy leaves even in the winter months.
Rouge d’Hiver: A cold-resistant romaine lettuce with reddish leaves that thrives in cooler temperatures.

If you’re growing in a greenhouse or polytunnel, you can also experiment with other lettuce varieties that might not tolerate frost as well but will still perform in protected environments.

Preparing the Soil for Growing Lettuce in Winter

Like all crops, lettuce benefits from well-prepared soil. Lettuce grows best in loose, fertile soil with good drainage. Because lettuce is a shallow-rooted plant, it doesn’t need very deep soil, but it does require a nutrient-rich environment to thrive.

Steps for Preparing the Soil:

Clear the Area: Remove any leftover plants, debris, or weeds from the area where you plan to plant your lettuce.
Amend the Soil: Lettuce thrives in slightly acidic to neutral soil (pH between 6.0 and 7.0). Add organic matter such as well-rotted compost or aged manure to boost soil fertility.
Improve Drainage: Ensure that the soil drains well, especially during the winter months when water can easily collect and lead to root rot. If necessary, raise the soil or use raised beds to improve drainage.
Fertilize: Lettuce is a light feeder, but adding a balanced fertilizer or slow-release nitrogen fertilizer can help support its quick growth. Avoid heavy feeding, as this can lead to bitter-tasting leaves.

How to Plant Lettuce in December

Once your soil is ready, it’s time to start planting your lettuce seeds or transplants. There are a few different methods for growing lettuce in winter, depending on your setup and location. You can plant lettuce directly in the garden with frost protection, or grow it in containers, a greenhouse, or a polytunnel.

Planting Lettuce Seeds

Direct Sowing Outdoors: If you’re planting outdoors, sow your lettuce seeds about 0.5cm (¼ inch) deep and space them about 20-30cm (8-12 inches) apart in rows. You can cover the rows with fleece, cloches, or plastic tunnels to protect them from frost.
Indoor Sowing: If you’re sowing seeds indoors, fill trays or small pots with seed compost. Sow seeds thinly and cover them lightly with compost. Keep the trays in a cool, bright location, such as a greenhouse or windowsill, where temperatures remain above freezing.

Planting Lettuce Transplants

If you’ve started your lettuce seeds indoors or bought young plants, transplant them outdoors once they have grown their first true leaves (about 4-6 weeks after germination). Space the plants about 20cm apart in rows. If you’re planting in a greenhouse or polytunnel, you can transplant directly into pots or grow bags.

Tip: If planting outdoors in December, always protect young lettuce plants with row covers, fleece, or cloches to shield them from frost.

Caring for Lettuce During Winter

Lettuce is relatively low-maintenance, but there are a few things you can do to ensure your lettuce crop thrives during the winter months.

Watering

Lettuce needs regular moisture to grow well, but be careful not to overwater, especially in winter when the soil may already be saturated from rain. Water your lettuce lightly, making sure the soil remains moist but not waterlogged. Be mindful of cold snaps, as frozen water in the soil can damage the roots.

Mulching

If you’re growing lettuce outdoors, consider applying a layer of mulch around the plants to help insulate the soil and regulate moisture. Mulching with straw or leaves can protect the soil from freezing and provide extra warmth for your lettuce.

Protecting Lettuce from Frost

While many winter lettuce varieties are frost-tolerant, extended periods of hard frost can still damage the plants. To prevent this, use cloches, row covers, or fleece to shield your lettuce from frost and cold winds.

If you’re growing lettuce in containers, you can move the pots indoors or to a sheltered area during particularly cold nights.

Pests and Diseases

Lettuce grown in winter is less likely to suffer from pests like aphids and slugs, but it’s still important to keep an eye out for any potential problems.

Common issues to watch for:

Slugs: Even in winter, slugs can damage your lettuce. Use slug traps or organic slug deterrents around your plants.
Fungal Diseases: Damp, cold conditions can lead to fungal diseases like downy mildew. Ensure good air circulation around your plants and avoid overhead watering to prevent fungal problems.

Harvesting Winter Lettuce

One of the best things about growing lettuce is that you can start harvesting relatively early, even during winter. Depending on the variety, lettuce can be ready for harvest within 6-8 weeks of planting.

Harvesting Tips:

Cut-and-Come-Again: Many types of lettuce can be harvested as “cut-and-come-again.” Simply snip the outer leaves when they are large enough to eat, and the plant will continue producing new leaves.
Full Heads: For varieties that form heads, wait until the head has matured and the leaves are firm before cutting the entire plant just above the soil line.
Frequent Harvesting: The more you harvest, the more your lettuce will grow. By regularly picking leaves, you encourage the plant to continue producing.

Once harvested, lettuce can be stored in the refrigerator for up to a week. However, for the freshest flavor, it’s best to pick lettuce just before you plan to use it.

Conclusion

Growing lettuce in December is a rewarding way to keep your garden productive throughout the winter months. Whether you’re sowing seeds directly outdoors or using the shelter of a greenhouse or polytunnel, lettuce is a resilient and easy-to-grow crop that will provide fresh, nutritious greens when few other plants are thriving.

By choosing the right varieties, preparing your soil properly, and providing protection from frost, you can enjoy a continuous supply of fresh lettuce throughout winter and well into spring.

Find out more things you can grow in December here