Trialing Lettuce Across Seasons: Varieties That Thrive in Cold and Heat

April 2, 2026

Head lettuce in our southern Victorian winters—cold, wet, and often frosty in July—can easily turn to mush. Many lettuce varieties perform beautifully in cool weather but struggle as days lengthen, while others tolerate summer heat yet lack vigour in the colder months.

In the 2020–2021 growing season, we trialed our entire lettuce collection to better understand which lettuce varieties could perform across seasons. We experimented with different sowing windows and grew crops in both protected and open field conditions. From these trials, a group of remarkable lettuces emerged—varieties with the rare ability to thrive in both cold-season, short-day conditions and the heat and long days of summer.

When to Sow Winter Lettuce

For winter lettuce production, our final sowing was in the first week of April. We sowed enough plants then to carry us through the entire winter.

Direct sowing while the soil was still warm worked very well. We also sowed trays in the glasshouse, where seedlings were ready for transplanting in just 21 days—much quicker than late winter sowings.

We planted them closely, four heads across a 75 cm bed with 15 cm between rows. By the time our day length dropped below 10 hours, we had a bed full of mini heads.

We farm in a frost hollow, so the heads that survived winter had some protection. Those exposed to frost were still edible but showed visible damage.

Each week we harvested the mini heads and mixed them with other frost-hardy greens to create a vibrant winter salad mix. They can also be sold individually as mini heads.

As daylight hours increased past 10 hours, the remaining plants began actively growing again—gaining mass and carrying us through late winter. These plants provided growth far quicker than lettuces sown in early winter.

Lettuce Varieties That Thrived in Winter

The varieties pictured throughout this post performed particularly well for us in winter:

Our trial spanned the entire planting season. Gem lettuces proved especially adaptable, performing well across all of the following sowing and harvest windows:

Early spring sown → early summer harvest
Late spring sown → summer harvest
Early summer sown → late summer harvest
Late summer sown → autumn harvest
Autumn sown → winter harvest (with frost protection)
Winter sown → spring harvest (with frost protection)

These lettuces also share a similar growth habit and mature size, meaning the packets can be mixed and sown together as a cut-and-come-again lettuce mix. Harvest at the perfect fork-sized stage with scissors and add edible calendula petals for colour—calendula also thrives in winter.

Although gem lettuces performed well across all planting windows, the time from transplant to maturity varies significantly by season. For example, a late autumn–sown gem lettuce should not be expected to reach harvest size in 35 days.

Grower Takeaway

Across our seasonal trials, gem lettuces consistently proved to be some of the most adaptable head lettuces we grow. Their compact habit, cold tolerance, and ability to restart growth as day length increases make them particularly useful for extending harvests through winter and into early spring.

For growers, this means one group of lettuce varieties can be used across multiple sowing windows—from spring right through to autumn plantings—simplifying crop planning while still producing high-quality heads.

Because these varieties share a similar growth habit and mature size, they can also be mixed and sown together as a cut-and-come-again lettuce mix, harvested young for salad blends or grown to full size as mini heads.