Fruit and Vegetable Gardening A-Z: Lettuces

Lettuce, one of the easiest vegetables to grow, comes in enough colors (from green to scarlet and purple), forms (heads or loose leaf) and flavors (buttery to tangy) to suit any palate. Microgreens, iceberg, crisphead and Romaine lettuces are the most popular types in the United States.

Hardiness Zones:
4-12 (Find your hardiness zone.)

When to Plant:
Sow seeds in late spring with successive sowings every three weeks (for a continuous harvest). Germination must take place in temperatures below 58 degrees. Sow the seeds 1/4 inch deep in the soil.

Soil must contain a lot of compost to feed the plants and help retain moisture. Make sure the soil pH is neutral.

Space Needed:
Spacing varies with each lettuce variety, so consult your packet of seeds.

Lettuce is intolerant to heat and will "bolt" (turn bitter) quickly unless you protect it from high heat. If you live in an area prone to hot summers, try planting Romaine lettuce, which is less likely to bolt under a light shade cloth. When the plants are about half-grown, apply a nitrogen-rich fertilizer to boost productivity. Water and weed diligently. Rabbits, deer, slugs, and snails are known pests that love to nibble on lettuces.

When to Harvest:
Harvest loose-leaf lettuces anytime after germination, though they are fully ready in 45-55 days. Pick the outer leaves only. Crisphead lettuces will eventually form a firm head that you can cut off at the soil level after 70-100 days; remove the roots and place in a compost bin. Romaine lettuce is ready between 75-85 days.

Average Yield:
One packet of seeds will produce roughly 30-40 pounds of lettuce.

Continuous Yield:
Looseleaf, yes; crisphead, no.

Life Cycle:

Difficulty Rating (1-5):