Tony O’Neill, gardener and author of the popular “Composting Masterclass” and “Your First Vegetable Garden,” combines lifelong passion and expert knowledge to simplify the art of gardening. His mission? Helping you cultivate a thriving garden. More on Tony O’Neill
Lettuce is an excellent season crop and can tolerate colder temperatures much better than it can temperatures above 85°F (29°C), which causes it to bolt.
Growing plants in the colder months can help reduce weed and insect pressures, and a mini hoop tunnel or cold frame can help safeguard crops when temperatures dip to the lower twenties (-5°C). Only needing 3 to 5 hours of sunlight, lettuce can be planted in warmer soil and mature in the cold.
What’s Not to Love About Winter Lettuce
Usually, spring comes, and a planting frenzy ensues, making every attempt to maximize the cooler spring months before the summer heat hits us. We seed plants indoors, ready to transplant after the last frost has passed.
Fall planting is just so different. Starting in warmer conditions, we’re looking to cheat the cold, and lettuce allows us to do so beautifully. Depending on where you live, several tried and tested lettuce cultivars will ensure you have fresh salads available most, if not all, of winter.
I’ve tried different cultivars across the five lettuce types, some with more success than others. Here I share my results from my trials using:
- Butterhead, Boston, or Bibb lettuce
- Crisphead or iceberg lettuce
- Romaine or cos lettuce
- Summer Crisp, French Crisp, or Batavian lettuce
- Leaf, cutting, or bunching lettuce.
Late-fall Lettuce Seeds
Just a point to note: Selecting only five is a challenge. I can name quite a few you can try, but the five I selected are top-notch winners. Below is a list of some of the varieties you should also consider.
|Solanova Green Butter
|New Red Fire
|Solanova Red Butter
Wide lettuce varieties, including butterhead, Romaine, and leaf, are ideal for winter production in mini hoop tunnels. It is critical to understand the growing requirements of winter lettuce, primarily the temperature and soil moisture needs, but also light levels.
Growing lettuce in a mini hoop tunnel allows you to extend the season, improve yields, and keep nutritious fresh salads a part of your diet throughout the winter. Your lettuce will grow successfully if you’re attuned to your region’s seasonal changes.
5 Lettuce Varieties to Grow in Winter
Below is my choice of hardy winter lettuces for winter salads. Note that some of these may be a challenge for the novice gardener. Although lettuce is one of the easiest crops to grow, growing them in cold temperatures may require cold frames or mini hoop tunnels.
1. Butterhead Lettuce (Winter Marvel and Salanova® Red Butter)
Butterhead lettuces are one of the most popular loose-leaf lettuce varieties. This loose-leaf lettuce has a sweet, mild flavor and a soft, buttery texture, making them perfect for a winter salad.
Its outer leaves are dark green and tightly packed, while the inner leaves are more delicate and pale green. When cut, butterhead lettuce has a round, rosette shape and is most often used in salads, sandwiches, and wraps.
If you live in warmer climates, consider one of the new Salanova® loose-leaf lettuces offering dense rosette heads with attractive, thin, supple leaves.
The Salanova® Red Butter loose-leaf lettuces offer good heads with a round base and emerald, loose leaves with a delicate, buttery flavor. Salanova lettuces (Green Butter and Red Butter) offer mini heads, and you can match the two for excellent outcomes.
2. Crisphead Lettuces (Nevada)
The Nevada crisphead lettuce is a variety of lettuce developed in Nevada. It is known for its green, sweet, crisp, crunchy texture and sweet flavor. The mild taste of lettuce is often used in salads and sandwiches.
The Nevada crisphead lettuce is very popular in the western United States and commonly found in grocery stores. It is an excellent source of vitamins and minerals, including vitamins A and K.
3. Iceberg Lettuce (Crispino)
Avoid growing crisphead and iceberg lettuces unless you have a cold frame to protect them from cold weather. Of course, you can give it a go if you have a hoop house.
Crispino lettuce is a hybrid created by crossing two popular varieties: the iceberg and Romaine. It is a crunchy, sweet-tasting lettuce with a mild flavor that works well in salads, sandwiches, or wraps.
It’s a great dietary fiber, vitamin C, and folic acid source. Crispino lettuce is also known for its high water content, which helps to keep you hydrated and helps to keep your hunger at bay.
4. Romaine Lettuce (Winter Density & Winter Wonderland)
Some lettuces stood the test of time for winter growing seasons that I could (should have included. The All-American Selection Rouge d’Hiver is one such plant that has been around for centuries and can be planted in late autumn.
The Winter Density is an heirloom plant offering sweet, crisp heads that grow between 8 and 10 inches (20 to 25 cm). It is highly cold tolerant, slow to bolt, and matures fast (55 days)
The Winter Wonderland Lettuce is an heirloom variety known for its large, green, frilly leaves with a mild, sweet taste.
It is often used in salads and adds a unique texture and flavor. This variety of lettuce is ideal for winter growing as it is slow to bolt and can withstand temperatures as low as 20°F/-6.7°C.
It is an excellent choice for adding texture and flavor to winter salad or as a garnish for winter dishes and can be planted as late as early November.
5. Leaf Lettuce (Black-Seeded Simpson)
Black-Seeded Simpson is a variety of lettuce known for its sweet, buttery flavor. It has a light green color, dark green veins, and a frilly texture.
The leaves have a crunchy texture, and the plant grows well in moist, well-drained soil. It is an excellent choice for salads, sandwiches, and stir-fries.
Black-Seeded Simpson lettuce is a fast-growing annual that is easy to grow and can be harvested in as little as 45 days. It is an excellent choice for gardeners who want a quick and easy harvest.
Winter Garden Requirements
Keep the pH between 6.0 and 6.5 and the soil well-drained to prevent root infections. Crop rotation is essential for reducing or eliminating soil-borne diseases such as Sclerotinia and Rhizoctonia.
Continuous soil moisture is required for seed germination during direct seeding and transplanting. The benefits of switching to drip irrigation are enormous, mainly for minimizing the spread of diseases.
During the cooler months, lettuce plants require significantly less water. Lettuce leaves should be kept as dry as possible to avoid foliar diseases such as gray mold and lettuce drops.
The length and intensity of daylight can affect the rate of lettuce growth. Lettuce plants can be kept in a mini hoop tunnel after growing and harvested as needed.
Lettuce needs at least three hours of sunlight but does well in low light.
Staggered planting from September to October (even early November) allows you to have a continuous supply of lettuce over an extended growing season. Start with shorter intervals of about three days, extending the gap to about two weeks as the season gets colder.
The desired maturity and the temperatures determine harvest dates during the growth period. If the crop proliferates, harvesting earlier than intended may be required to ensure optimal airflow around the plants, reducing risks of foliar infections.
Depending on the temperature, harvesting time might range from 50 to 80 days. Cooler soil temperatures will increase the amount of time between planting and harvesting.
How to Grow Lettuce
Growing Lettuce from Seed
Lettuce germinates about seven to fourteen days after planting in soil temperatures between 60 and 70°F (15.5 – 21°C). Depending on temperatures, plant lettuce seeds directly into the garden in growing transplants in flats.
Lettuce seeds are susceptible to soil-borne pathogens and will grow successfully if seeded in flat trays. An inert growing material will ensure good germination between 2 and 10 days after planting.
Germination is light-dependent, and seeds need to be kept moist throughout. Any interruption in moisture supply will kill the seed or baby lettuce.
The Importance of Thinning When Growing Lettuce
When the baby lettuce is a few inches tall, and the soil in your garden has been prepared, transplant them four to six inches apart. Water them regularly until the plants are established.
Thin them to a final spacing of ten to twelve inches when they are about six inches tall. Weeds can be controlled by mulching or periodic cultivation, and nitrogen-rich natural fertilizers such as kelp meal and fish emulsion can be used as needed during the growing cycle.
This thinning process is vital for heading lettuce cultivars as it ensures enough space for good air circulation and keeps lettuce disease-free until they reach maturity.
The two leading causes of foliar infections in your garden are wet leaves (overhead irrigation) and insufficient air circulation. If you don’t space your growing lettuce correctly, your heads may not form as they compete for water and nutrients.
Cold Frames and Hot Boxes
Plant early, transplant early, and aim to harvest before the ground freezes. If you grow lettuce in USDA Hardiness Zone 1 or 2 in winter, consider using a mini hoop tunnel or a cold frame.
A cold frame is a built environment with a slanted glass door or window that is South-facing, allowing heat-trapping UV rays to enter but not escape. This caused the inner chamber to heat up.
If you’re living in the colder North and want to garden, I strongly suggest you invest in building a cold frame of a hot box. A hot box is a cold frame that doesn’t only rely on the sun’s energy but has internal heating mechanisms as well.
Lettuce is quite happy in cool temperatures, and you can grow lettuce quite comfortably in temperatures around 40°F/4°C—the five listed cultivars above all cold hardy. The whole table listing lettuce plants is classified as cold-hardy and ideal for growing a winter salad.
The germination temperature must be between sixty and seventy (or as low as 45°F/7°C), but the colder it is, the longer the germination takes, extending the risks.
Plant hardier leaf lettuce varieties and other leafy greens for continued winter salad making. The initial gap should be about three days apart, planting only a few seeds.
These seeds will germinate fast, and you’ll harvest lettuce in about 55 days. As the soil temperatures cool, extend the gap between the plantings to extend your harvest season.
FAQs on Lettuce Varieties to Grow in Winter
What is the most heat-tolerant lettuce variety?
Among lettuce varieties, the most heat-tolerant option is Summer Crisp lettuce. This lettuce type is also known as Batavian lettuce and is a cross between crisphead and loose-leaf lettuces. Summer Crisp lettuce can tolerate higher temperatures than other lettuce types, making it a popular choice for gardeners in warmer climates. Its crunchy texture and slightly sweet flavor make it a great addition to salads and sandwiches. You can easily find more information about this variety by using relevant keywords such as “heat-tolerant lettuce” or “Summer Crisp lettuce” in your search.
What is the most frost-tolerant lettuce?
There are several frost-tolerant lettuce varieties, but some of the most popular ones include Winter Density, Arctic King, and Rouge d’Hiver. These varieties can withstand temperatures as low as 20°F (-6°C) and can be grown in mini hoop tunnels or cold frames to provide added protection. Winter lettuce is an excellent option for cold-season gardening and can be a reliable source of fresh produce during winter. When searching for the most frost-tolerant lettuce, consider these varieties and ensure you are attuned to your region’s seasonal changes for success.
What is the best variety of lettuce to grow?
The best variety of lettuce to grow depends on factors such as growing region, climate, and personal preference. However, some popular lettuce varieties for home gardeners include Butterhead, Romaine, Leaf, Crisphead, and Summer Crisp. Butterhead lettuce is sweet and mild with a soft, buttery texture, while Romaine lettuce is known for its crisp leaves and intense flavor. Leaf lettuce is easy to grow and comes in various colors and textures, while Crisphead lettuce, also known as an iceberg, has a crunchy texture and mild flavor. Summer Crisp lettuce is a newer variety with a crispy texture and sweet flavor. Ultimately, it’s recommended to try growing different lettuce varieties to find the ones that thrive in your growing conditions and suit your taste preferences.
Whether it’s cor salad you’re after or baby lettuce greens, these cold-hardy varieties will ensure a continued supply of winter salad. A row cover will help protect against pests early on before the winter months when pests are less of a problem.
Lamb’s quarter (purslane or Portulaca oleracea) isn’t a lettuce but is excellent with sweet corn relish in corn salad. It is also hardy and one of the richest sources of omega-3 fatty acids, lowering lipid levels in the blood.
I listed five varieties, but several others are not mentioned, like the red oakleaf and the minminer’sttuce (which isnisn’tttuce but is exceptionally hardy). I hope your winter garden will flourish, even in colder weather.