Lactuca sativa – Lac, latin for ‘milk’ referring to the white sap, and sativa for ‘cultivated’.
The origin of cultivation dates from early days in the temperate parts of Caucasus (Azerbaijan and Georgia), in Kurdistan, Kashmir and Siberia. The Romans grew a pointed, narrow-leafed Cos just like the Rabbit’s Ear lettuce that we know today. It was only in the 16th century that the head lettuce was described for the first time.
Lettuces need to grow fast with adequate water in hot Australian summers. They’ll do better and are more tender grown under a shade cloth or a bush than in full sun. To ensure that Romaine lettuces heart up, it’s best to grow them close to each other. Tender hearts can also be obtained by binding the leaves together as they grow.
For cool areas with a short growing season, crisped types will need to be started in a hothouse to become mature enough to produce seed.
Saving The Seed
Saving the seeds of lettuces is simple, and a great place for beginners to start. If you leave a lettuce unattended for long enough, it will elongate, go to seed and self seed within a short time. Lettuces are self pollinating, but all the same, a very small amount of cross-pollination can occur – from one to six percent when two varieties are grown side by side. A two- to three-metre barrier or a tall crop between different varieties flowering at the same time is sufficient to reduce the crossing to zero.
From the edible stage when you’d normally harvest for the table, it takes two months to bring the crop to the ripe seed stage. The yellow-flowered seed stalks often need staking and the seeds can easily be dislodged. They ripen progressively and when two thirds of the flowers are turning fluffy white, like thistles, the plant can be cut and put out to dry on a large sheet of paper.
The first seeds to ripen on the plant are said to be the best fed and most suitable for seed stock. In wet climates, seeds need to be harvested between rains. The whole plant can be harvested early by hanging it upside down and the seeds will ripen, as the thick stem continues to supply the necessary nutrients.
Once completely dry, seed heads are rubbed between the hands until the thousands of little capsules pop open. Three quarters of the mass will be chaff and fluff which can be separated using a sieve or by restrained winnowing – but don’t be afraid to lose a few during this process, a good plant will yield up to 60,000 seeds. The seeds are a flat, long oval shape with pointed ends; they are black, brown or white depending on the variety.
When stored in the best conditions – dry, cool and dark – lettuce seeds will remain viable for up to five years. Otherwise they will lose up to 50 percent of their viability in just two years, and 90 percent in three years, especially in the tropics. There’s about 1000 seeds to the gram.
Delicious mixed lettuce salads are made with torn pieces of leaves that are tossed in vinaigrette before serving. Mesclun is a southern French salad of young seedlings of mixed lettuces, rocket, sorrel, fennel, parley, chicory, endive and so on, that are planted and harvested together.
On The Lookout
Lettuce can be divided into four types: heading crisphead lettuce, heading butterhead lettuce, Romaine lettuce and looseleaf lettuce. Because of their popularity and wide distribution, lettuces have been brought to Australia by many cultures. Greeks introduced Cos, Italians brought Romaine, while Chinese brought numerous varieties including a large, spreading, looseleaf type with red tinges. These came in 1860 to Victoria’s Ballarat region, today aptly called Gold Rush lettuce.
This is an edited extract from Michel and Jude Fanton’s book The Seed Savers’ Handbook: A Permaculture Seed (Seed Savers Network 2020) www.seedsavers.net