With its soaring temperatures and long days, summer is a great time of year for fresh, light salads. No picnic or BBQ is complete without a big bowl of crisp greens tossed in a summery dressing, and it’s even better if the lettuce is homegrown.
Lettuce plants (Lactuca sativa cultivars) traditionally favour cooler climates, having a tendency to bolt in the heat. However, there are a number of heat tolerant varieties available, and these are perfect for growing in summer – simply add plenty of water and a bit of shade. Here are some of our favourites.
Top Lettuces for Summer Planting
Great Lakes is the summer lettuce. Remarkably heat tolerant, this is a large variety that produces crisp heads with great flavour – perfect for summer salads. The seeds can be sown in successive rounds, and the heads harvested at 8 weeks.
Sow in clumps of a few seeds each, 30cm apart and at a depth of 6mm. Cover lightly with soil or seed raising mix and water gently. As seedlings emerge, thin out to the strongest ones. Apply liquid fertiliser every 10-14 days, and provide plenty of water.
As the name suggests, All Year Round is suitable for planting at virtually any time. This variety produces tight, solid hearts on a very hardy plant able to tolerate a variety of temperatures. Plant seeds in succession at fortnightly intervals, and harvest at 8-12 weeks.
Sow thinly at a depth of 5mm, in rows spaced 25-30cm apart. Ensure the soil moist as they germinate, thinning to 20-25cm apart as seedlings develop. Keep plants well-watered and free of weeds as they grow. This variety is also available as seed tape.
This mixed blend of seeds is a great way to grow lettuces in a variety of colours, shapes and textures – perfect for gourmet salads. These tend to be loose leaf varieties, which can be harvested with a ‘cut and come again’ approach (individual leaves) or as a whole head.
Sow in clumps, each containing a few seeds at 6mm deep. Space clumps 10cm apart. Cover lightly with soil or seed raising mix and keep moist. Thin to the strongest seedlings as they develop. Apply liquid feed every 10-14 days and water well.
Our salad leaf mix has everything you need for the traditional green salad found in Mediterranean cuisine. Individual leaves are picked when very young before any hearts develop, and the plants simply produce more in their place. Sow as described above.
What not to plant
Can we plant cos lettuce in summer? What about iceberg?
This is a commonly asked question, perhaps because iceberg and cos are among the most well-known lettuce varieties. In most areas, however, these varieties are best planted in spring or autumn. They are simply not heat tolerant and will bolt rapidly.
Caring for your plants
Planting lettuce in summer means watering, and plenty of it. Lettuce plants have shallow root systems, which means they rely on water in the part of the soil that loses moisture most rapidly. Keep them topped up daily for happy plants.
Positioning is important when it comes to planting lettuce. Late summer is often the hottest time of year, and the afternoon sun can be extremely harsh, so ensure your lettuces are planted somewhere that can be shielded from UV rays at this time. A shade cloth is a good idea, or simply choose a position that is naturally shaded in the afternoon.