Native to Asia Minor and once eaten by the kings of Persia, lettuce crossed the Atlantic with Christopher Columbus when he arrived in Haiti. Despite the early arrival, lettuce didn’t become a popular vegetable in North America until the 20th century when its high water content and low caloric density made it a staple diet food. However, lettuce is more than just low-calorie fibre and the tossed salad your mom served with every dinner.
Types
There are two main types of lettuce: head lettuces like iceberg, romaine and butterhead varieties (Boston and Bibb), and leaf lettuce that comes in red, green and oak.
- Iceberg – the most widely grown and eaten lettuce, known for its semi-sharp flavour and crunchiness. It makes excellent salads and often comes wrapped in plastic to prevent leaf damage.
- Romaine – a sturdier lettuce with a long oval-shaped head and layers of dark green leaves. It is commonly used in Caesar and Greek salads as it holds up well to heavier dressings.
- Butter lettuce (Boston and Bibb) – Butterhead or buttercrunch lettuces have a subtle, sweet flavour and soft, velvety round leaves that make the perfect base for lettuce wraps and low-carb “taco’ shells. These are specialty lettuces and are often more expensive.
- Leaf lettuce (red,green,oak) – These kinds of lettuce have tender leaves that are torn from a simple stalk at harvest, often purchased as ‘baby lettuce’ and in spring mixes. It comes in three main types: green, red and oak. Red leaf lettuce is a burgundy shade and has a mild flavor like its green counterpart, while oak leaf is spicier and nuttier in flavour.
Despite being green and leafy, kale is not a lettuce. It belongs to the crucifer family and is more closely related to cabbage and cauliflower than Romaine. Kale is packed with fibre, iron, calcium and vitamins K, A and C and adds a nutrient boost to any salad.
How to Buy
Lettuces are cool weather crops and are at their best in the spring and early summer.
Look for firm dense heads with crisp leaves that are free from brown or soft spots, have a bright colour and fresh smell. Look for lettuce that has been picked as recently as possible by inspecting the ends and avoiding any that looks rusty, dried out or wilted. However, you likely can’t avoid all damage, and some spotting, holes and minor damage is common. If this is confined to the outer leaves they can be discarded.
If buying packaged lettuce mixes or pre-chopped salads, check the expiry date and inspect to ensure the leaves are rust free and there are no soft or spoiled leaves in the bag. Take the time to give it a rinse when you get home.
To save money, you can make your own salad mixes by buying bulk head or leaf lettuces, rinsing and draining them well, tearing into salad sized pieces, mixing them together and refrigerating in a sealed container for up to 5 days.
How to Store
Store your lettuce in the refrigerator’s crisper drawer to maintain the proper temperature and moisture level.
Wash and wrap loose leaf lettuce in a towel or paper towel and place it in a plastic bag or storage container, or leave it in the original packaging if it came prewashed.
Do not wash head lettuce until you are ready to prepare and eat it.
Iceberg heads can keep in your fridge for up to two weeks when unwashed and stored in their original plastic. It will last twice as long as other varieties.
Butter lettuce, particularly Bibb, is often sold as ‘living lettuce’ and comes in clamshell packs with the root still attached. Add a couple of ounces of water around the root to extend the shelf-life of butter lettuce in your refrigerator.
How to Wash Lettuce:
Whether buying it from the grocery store, hand selecting it from your favourite farmers market stall or picking it from your back yard, don’t wash your lettuce until you’re ready to eat it – to extend the storage life.
This method of washing works best for head lettuce, loose leaf and bagged lettuce:
- For head lettuce and Romaine, remove any damaged leaves. Break the rest of the leaves off the stem and tear them into smaller pieces. Avoid cutting with knives as this causes oxidation and browning along the cut edges.
- Fill a bowl or sink with cool water and swish the torn leaves gently to dislodge dirt and debris. This will sink to the bottom while your leaves float.
- Lift the greens and move them to a clean towel or colander to drain and then thoroughly pat dry with paper towel. Or if you have a salad spinner, now is the time to use it.
- Lay your leaves out on a few layers of dry paper towel or a clean kitchen towel and then roll them up with the lettuce inside for storage. The towel will absorb remaining moisture but keep them damp enough to prevent wilting and significantly extend the storage life.
How to Prepare
Iceberg – The classic salad base, iceberg lettuce can be chopped, shredded or cut into wedges, mixed or topped with your choice of accoutrements and drizzled or tossed in your favourite dressing or a Simple Vinaigrette.
Romaine – Although there is nothing wrong with a good old fashioned Caesar salad, romaine’s sweet and bitter crunch lends itself well as a fresh ingredient in shawarma, wraps, pitas and these Mediterranean Beef and Barley Koftas. If Caesar is still your favourite, mix it up with this Anyday Potato Caesar Salad from Dairy Farmers of Canada.
Butterhead – The tender leaves of butter lettuce work best in delicate salads, but their broad, flexible leaves can also be used as a wrap like these Roast Beef Salad Rolls or our Lettuce Wrapped Swiss & Bacon Burger.
Leaf – Leaf lettuces come in beautiful green and red/purple colours, have delicate leaves and a subtle flavour. They are excellent in sandwiches, burgers and wraps. They also add a colourful, textural component to salads, but avoid dressing leaf lettuces until just before serving to avoid wilting. If you need some inspiration, here are some ideas to make healthy, meal-sized salads.
Nutrition Facts
Lettuce is low in calories, and a good source of Vitamin A, Vitamin C and folacin.
As a general rule of thumb, the darker green the lettuce variety is, the more Vitamin A it contains.
How They Are Grown
Lettuce is a cool-hardy vegetable that is well suited to Canada’s climate and soil zones. It is frost resistant and is planted early in the spring in fields in Quebec (50%), Ontario (40%) and British Columbia’s Lower Mainland and Vancouver Island (10%), as well as backyards across the country.
Of the almost 80,000 MT of lettuce produced in Canada in 2020, 60% of it was head lettuce, while the remaining 40% of production was leaf lettuce varieties.
Lettuce can be grown in fields or in greenhouses.
Field lettuce is seeded in a greenhouse in early spring and then transplanted outside in fields of rich black dirt as soon as the ground can be prepared. Some producers seed the lettuce directly into the field.
Leaf lettuce is harvested about 50 days after planting, while head lettuce takes closer to 75 days. Lettuce is planted in consecutive plantings so that there is a supply available throughout the growing season. That is, as soon as the first planting has emerged, the second planting is seeded.
Head lettuce is harvested with the help of a mechanical harvester and workers who remove damaged leaves and pack them into boxes in the field. Leaf lettuces are usually harvested by hand and packed into cartons in the field as well. The lettuce is then shipped in refrigerated trucks to retain its freshness and stored in a carefully temperature controlled environment to maintain maximum quality for a short time before being shipped to the store.
There is also a small amount of lettuce being produces in greenhouses year round in Quebec and Ontario. In greenhouses, lettuce is seeded in peat blocks and transplanted to the final media in 2 to 3 weeks in the summer or 4 to 6 weeks in the winter. The most common kind of lettuce grown in greenhouses is butterhead lettuce. The full cycle takes 6 to 7 weeks in summer and 10 to 12 weeks in winter. The time difference is due to the shorter days and amount of available sunlight.
Although the majority of Canada’s 650 greenhouses operate on natural gas, some have made tremendous advancements in the area of solar power, water and heat recapture. This means that they recycle their waste water and are able to capture waste heat and C02 to reduce carbon emissions. When combined with solar power, the greenhouses can make themselves self sufficient for electricity and heating. Vertical farming, hydroponic growing systems and controlled environment agriculture (CME) are also on the rise.
Canadian Field Crop is Available:
Leaf – May – End Oct
Head – Mid June – Mid Oct
Canadian Greenhouse Crop is Available: Year round
Grown in: Quebec (50%), Ontario (40%), British Columbia (10%)
Industry Websites
- Ontario Greenhouse Vegetable Growers – https://www.ogvg.com/
- Ontario Fruit & Vegetable Growers Association – https://www.ofvga.org/
- Quebec Produce Growers Association – https://apmquebec.com/
- Eat Quebec – https://mangezquebec.com/en/