Botanical name: Lactuca sativa
Plant type: Vegetable
Sun exposure: Part Sun
Soil type: Loamy
This is a half-hardy vegetable that you can keep growing all season long by planting one small crop at a time. Days to maturity tend to be short. Garden lettuce is far superior, in both taste and vitamin A content, to supermarket brands.
- Lettuce is a cool-season crop. While you should avoid planting in the middle of summer, you can get multiple crops in spring and late summer.
- Take extra care if planting crisphead varieties; they will not survive a hot spell.
- Start seeds indoors 4 to 6 weeks before last spring frost date for earliest crop.
- Till in compost or organic fertilizer 1 week before transplanting.
- Harden off seedlings for about a week, and transplant outside between 1 week before and 2 weeks after last spring frost.
- Leaf lettuce: Plant 4 inches apart.
- Cos and loose-headed types: Plant 8 inches apart.
- Firm-headed types: Plant 16 inches apart.
- Water thoroughly at time of transplant.
- Fertilize 3 weeks after transplanting.
- Direct sowing is recommended as soon as the ground can be worked. Plant seeds ½ inch deep. Snow won’t hurt them, but a desiccating cold wind will.
- You should be able to sow additional seeds every two weeks.
- To plant a fall crop, create cool soil in August by moistening the ground and covering it with a bale of straw. A week later, the soil under the bale will be about 10 degrees F (6 degrees C) cooler than the rest of the garden. Sow a three foot row of lettuce seeds every couple of weeks—just rotate the straw bale around the garden.
- Consider planting rows of chives or garlic between your lettuce to control aphids. They act as "barrier plants" for the lettuce.
- Fertilize 3 weeks after transplanting. Lettuce prefers soil that is high in humus, with plenty of compost and a steady supply of nitrogen to keep if growing fast. Use organic alfalfa meal or a slow-release fertilizer.
- Make sure soil remains moist but is well-drained.
- Retain moisture with mulch throughout the summer months.
- Lettuce will tell you when it needs water. Just look at it. If the leaves are wilting, sprinkle them anytime—even in the heat of the day—to cool them off and slow down the transpiration rate.
- Some thinning may be required for directly sown seedlings; use the space guidelines above.
- Weed by hand if necessary, but be careful of plant roots: They are shallow.
- Lettuce should be harvested just before maturity. Pay attention to the leaf size. Before maturity, you can break leaves off. As time passes, you will want to cut the whole plant from the ground.
- Mature lettuce will go bad quickly, so check your garden everyday.
- It’s best to harvest in the morning before leaves have been exposed to sun.
- Keep lettuce in the refrigerator for up to 10 days in a loose plastic bag.
- Lettuce wilted? Put the leaves in a bowl of cold water with ice cubes and soak for about 15 minutes.
- Crisphead: 'King Crown', 'Mission'
- Cos (Romaine): 'Wallop', 'Paris White Cos'
- Loose Heads: 'Burpee Bibb'
- Red Leaf: 'Red Sail' (Not recommended for hot weather, their red pigment absorbs more heat.
Wit & Wisdom
Lettuce is a member of the sunflower family.