How to grow lettuce from seed
The lettuce, usually the main ingredient of any number of salads, has been cultivated since Ancient Egyptian times, and was offered to their god of fertility.
It was also believed that the lettuce cured impotence and had aphrodisiacal properties.
It was also believed that the lettuce cured impotence and had aphrodisiacal properties.
Types of lettuce
There are 4 main types of lettuce that differ in shape, size of leaf, texture, colour and taste:
- Romaine or Cos that produces long crispy leaves
- Butterhead with varieties such as Bibb and Tom Thumb, where the leaves are loosely formed, softer and the head resembles a flower
- Crispheads or Iceberg. The leaves are pale and crunchy and the lettuce has a similar shape to the cabbage
- Looseleaf like Lollo Rosso and Oakleaf have vivacious green, tight and curly leaves
Soil conditions for growing lettuce
Lettuce plants thrive in any type of soil that retains moisture, drains well and has been prepared with lots of organic matter. The soil should be nutrient-rich and have a pH of 6.5. Lettuce can be planted in heavy or light soils including sandy and even loamy earth so long as moisture is present and can be obtained from below.
Climate conditions for growing lettuce
Cooler temperatures between 4 - 15°C (40 - 60°F) are ideal for growing lettuce. The lettuce will survive through frost but only frosts of a light nature. The seeds should be planted in a sunny spot, or a partially shaded area during the summer when temperatures are higher. The lettuce does not like extremes of temperature in either direction.
When to plant lettuce seeds
Check the seed packets of your chosen type of lettuce for when to plant outside as there are spring and summer varieties. Most types can be planted in the open air from March or the beginning of April; or sooner, in February if grown under a cloche, cold frame or started indoors or in a greenhouse.
Soil preparation
Prepare the area where you are going to sow your lettuce seeds several months prior to planting, in autumn or winter. Dig the soil to about 1ft deep, remove any stones and debris and add plenty of well-rotted compost or manure, which is essential for moisture-retention. A week before you are due to start planting, rake over the soil to form a fine tilth, and apply a light general fertiliser.
Sowing the lettuce seeds
Once your bed is ready, form several rows of drills with your hoe. The drills should be 30cm (12 inch) apart and 12mm (1/2 inch) deep.
The trick with lettuce is to sow a few seeds (3 - 4) every 2 weeks up until June or July. This will ensure a steady supply of lettuce throughout the spring and summer, rather than a big glut all at once. Leave a distance of 15cm (6 inch) between each plant. Cover the seeds loosely with soil and water.
The trick with lettuce is to sow a few seeds (3 - 4) every 2 weeks up until June or July. This will ensure a steady supply of lettuce throughout the spring and summer, rather than a big glut all at once. Leave a distance of 15cm (6 inch) between each plant. Cover the seeds loosely with soil and water.
Thinning out
The lettuce seeds will germinate fairly quickly, usually within 7 - 14 days and should be thinned out to avoid overcrowding. Remove the weaker seedlings once they reach approximately 5cm (2 inches) tall and leave 7 - 10cm (3 - 4 inches) between each plant. When they have grown a further inch, thin out again to 15cm (6 inches) and finally to 25cm (10 inches).
Caring for the lettuce plants
Lettuce plants require an abundance of water, although they should not be saturated as this could lead to disease in the same way that a lack of water will. Water in the morning for optimum results, and as the best quality lettuces are produced when grown at a fast pace, you may wish to apply a light general fertiliser. Ensure that weeds are removed and mulch around the plants once they have started to grow.
Protection against pests
To protect the lettuce plants against birds, you can cover them with a wire netting or mesh. Slugs can be kept at bay using a variety of methods, but always try to use the one that is most friendly to the environment and any other animals. Nowadays it is possible to buy eco-friendly pellets, or alternatively place sand or grit around the plants, which the slugs find difficult to slide over.
Greenfly and aphids can be a particular problem. You may have to use a spray to rid the lettuce of these pests and dig up any affected plants.
If any other signs of disease are observed, remove the affected leaves and spray the plants with eco-friendly chemicals. It is best to ask for advice on which to use from your local garden centre.
Greenfly and aphids can be a particular problem. You may have to use a spray to rid the lettuce of these pests and dig up any affected plants.
If any other signs of disease are observed, remove the affected leaves and spray the plants with eco-friendly chemicals. It is best to ask for advice on which to use from your local garden centre.
Harvesting the lettuce
Depending on the variety, the lettuce should be ready to harvest some time in between 6 - 15 weeks from sowing. The lettuce can be cut from the ground once the heart has formed and becomes firm. To test this, just press down gently on the heart with the back of your hand - squeezing an immature lettuce can lead to disease.
Use a trowel to loosen the roots and pull the lettuce out from the ground. There are some varieties that should be cut at the base, which is then left in the ground for a new plant to grow in its place.
Use a trowel to loosen the roots and pull the lettuce out from the ground. There are some varieties that should be cut at the base, which is then left in the ground for a new plant to grow in its place.
