Everyone in France is familiar with corn salad (also known as lamb’s lettuce or mâche in French), but in Canada, this little vegetable is still little-known and not easy to find in stores. It’s been grown since ancient times in Egypt and since the Renaissance in France, but it wasn’t until the 19th century that restaurateurs gave it its letters of nobility. France is currently the world’s leading producer of lamb’s lettuce.
Mostly eaten as a lettuce, it is nevertheless a member of the valerian family. It has many qualities, but for my part, I’m particularly interested in its resistance to cold, which makes it one of the rare vegetable plants that can be eaten at home until it snows. And what’s more, you can protect it with a floating row cover until the first real snowstorm discourages you from the garden for good. I’ve already harvested some at Christmas, when the snow was late in coming. Corn salad has a very mild flavor, unlike other late “lettuces” like escarole, which are quite bitter.
Growing Corn Salad
Here, in Quebec, it can be sown as early as the beginning of April for harvesting 6 to 8 weeks later, but as it does not tolerate heat well, it is safer to wait until the summer heatwaves have passed. Sowing can start in early August and continue until mid-September at the latest, for harvesting throughout the autumn. It will survive our harshest winters in the open ground, and can be eaten again in spring until it goes to seed.
With a little protection, it looks like it can be harvested throughout the winter: in unheated greenhouses or cold tunnels, but I leave that to professionals like Jean-Martin Fortier, who harvests it all winter under unheated cover, when the thermometer can drop to -30°C (-22°F)! This year, I’m still going to protect it with geotextile fabric before the first snowfall to prolong my harvest. In winter, I grow sprouts in pots and small shoots on potting soil.
Lamb’s lettuce prefers sandy soil, but will also grow well in good garden soil with added compost. Sow in rows about 4cm (2″) apart.
How to Eat It
Although lamb’s lettuce can be cooked, it’s better to eat it raw, as it contains a lot of beta-carotene: a source of vitamin A that has antioxidant properties and can improve certain immune system functions. Some studies even link the consumption of foods rich in beta-carotene to a reduced risk of certain cancers. Corn salad also contains vitamins C and B12, as well as iron, calcium, copper, manganese and potassium. Lamb’s lettuce also contains a small amount of omega-3 fatty acids, found mainly in oily fish and oils.
The leaves form rosettes that are harvested in their entirety. Back in the kitchen, I cut the base of the rosette to free all the leaves and discard those on the periphery, which are often less attractive. Lamb’s lettuce keeps well in the fridge in a plastic bag or box, but when it’s time to eat it, I add a mild vinaigrette at the last minute, as the leaves are fragile.
A real treat when there hasn’t been a single lettuce in your garden for ages, and we have to make do with imported produce!