Scientifically called Lactuva sativa, lettuce is an annual plant that belongs to the family Asteraceae. Lettuce is one the salad crops grown commercially across the world. The demand for lettuce is increasing day by day due to the health benefits and the ease of use. In the early 21st century, bagged salad products increased in the lettuce market, especially in the US where innovative packaging and shipping methods prolonged freshness.
Traditionally, lettuce can be cultivated in rich soils, and although this is the most common way of growing, it does come with the risk of pests and insects.
Though lettuce looks like cabbage, one difference between the two is the water content – cabbage has less water and is also tougher than lettuce. Lettuce is crunchier.
Amazing health benefits of lettuce.
- High in Fiber and Cellulose
A reason it is good for weight loss.
This fiber also helps remove bile salts from the body. When the body replaces these salts it breaks down cholesterol to do so. This is why lettuce is also good for your heart!
- Anti-inflammatory Agent
Lettuce possesses anti-inflammatory properties that help in controlling inflammation. In experimental models, lettuce extracts have shown significant controlling power over inflammation induced by biocatalysts like lipoxygenase and carrageenan.
- Promotes Brain Health
Extreme cases of brain harm can lead to the death of neuronal cells, leading to severe brain diseases like Alzheimer’s. The lettuce extracts, as per numerous studies, had controlled this neuronal cell death due to its role in GSD or glucose/serum deprivation.
As per another study, lettuce is also rich in dietary nitrate. This compound is converted to nitric oxide in the body, which is a cellular signaling molecule that promotes endothelial function. The reduction of endothelial function contributes to cognitive decline and other neurological disorders related to aging .Intake of lettuce stops this.
- Reduces Diabetes Risk
Studies have shown that greens, especially those like lettuce, reduced the risk of type 2 diabetes. This can be attributed to the low glycemic index (the effect of a particular food on your blood sugar levels) of lettuce, which means it doesn’t cause much of a rise in blood sugar levels.
Also, one cup of lettuce contains just about 5 calories and 2 grams of carbs. This fact also makes it a healthy addition to a diabetes-friendly diet. Reports recommend romaine lettuce over any other variety as it contains essential micronutrients (which is why it is darker).
Lettuce also contains lactucaxanthin, an anti-diabetic carotenoid that lowers blood glucose levels and can be a potential treatment for diabetes
- Helps with Insomnia
The white fluid that you see when you break or cut lettuce leaves is called lactucarium.
Lactucarium has relaxing and sleep inducing properties similar to opium but without the strong side effects. Simply eat a few leaves or drink some lettuce juice.
Lettuce should be spaced to accommodate light mechanical tillage. The spacing will vary according to the size required and the type of lettuce grown. For heading types, a good starting point is about 60 000 plants/ha. If you are not planting on beds, use closer spacing within the row and leave a gap between rows to accommodate a cultivating implement, if required.
As this is a transplanted crop, there is no need for fine land preparation and small clods are acceptable and often beneficial. The more we cultivate, the more we destroy the soil structure.
Climatic and cultural requirements
Lettuce thrives at relatively cool temperatures and requires ample sunlight, uniformly cool nights, and plenty of moisture in the soil for well developed, solid heads.
Optimum temperatures for growth are 18.8– 22.70C during the day and 7.2–110C at night. High temperatures generally above 290C are conducive to early flowering resulting in low quality and bitter flavour.
At temperatures above 23.80C, firm heads are difficult to obtain, and stems tend to elongate. Plants will withstand freezing, but below 7.20C, growth is extremely slow.
As plants approach maturity, they are more easily injured by freezing than when they are young and injured tissues become more susceptible to soft rot.
Lettuce can be grown on a wide range of soil types, depending on irrigation, drainage, and local climatic conditions. The soil pH should be 6.5-7.2.
when seedlings sprout to about 2-3 inches, they should be thinned to 3-4 inches apart. This helps in reducing competition as well as ensuring sufficient air circulation within the crops.
Mulching helps to keep the soil moist and to suppress weeds. Decomposed mulch releases nutrients into the soil, which are absorbed by the crop. It also helps prevent soil erosion.
Lettuce is propagated from seed.
Seedlings are transplanted about five weeks after sowing.
They should be watered about an hour before uprooting them from the nursery, in order to prevent root damages.
Transplanting should be done on a cloudy day or late in the evening when the sun is cool.
It takes 1.5–3 months from planting to harvesting, which continues for about four weeks. The leaves taste best when they’re still young and tender. Before maturity, you can harvest leaf lettuce by simply removing outer leaves so that the center leaves can continue to grow.
- Butterhead types can be harvested by removing the outer leaves, digging up the whole plant, or cutting the plant about an inch above the soil surface. A second harvest is often possible when using the first or third methods.
- Crisphead lettuce is picked when the center is firm.