Growing Lettuce: Cool-Season Crops for Continuous Salad Harvests

Lettuce is a cool-season crop thriving in spring and fall. Seedlings tolerate light frost. Ideal temps: 45–65°F. Garden lettuce surpasses supermarket in taste and Vitamin A.

Because lettuce grows fast, plant small amounts staggered for continuous harvest.

Planting Lettuce

Prepare soil: loose, well-drained, moist not soggy. Add organic matter 1 week before seeding/transplanting. Well-tilled seedbed essential—large clods reduce germination.

• Direct sow as soon as ground workable. Seeds ½ inch deep. Snow OK; desiccating cold wind harms.
• Earlier crop: start indoors 4–6 weeks before last frost. Harden off ~1 week, transplant 2 weeks before to 2 weeks after last frost.
• Sow single rows or broadcast for wide rows. Broadcast requires thinning for spacing:
  • Leaf lettuce: 4 inches apart.
  • Cos/loose-headed: 8 inches apart.
  • Firm-headed: 16 inches apart.
• Rows 12–15 inches across.
• Cover seeds ¼–½ inch soil.
• Water thoroughly at transplant.
• Plant chives/garlic between lettuce as “barrier plants” for aphid control.
• Indoor growing? See blog.
• Fall/winter planting possible. See second crop tips.

Care

• Sow additional seeds every 2 weeks for continuous harvest.
• Fertilize 3 weeks after transplanting. Lettuce likes high humus, compost, steady nitrogen. Use organic alfalfa meal or slow-release fertilizer.
• Fall crop: cool soil in August by moistening ground, covering with straw bale. Week later, soil under bale ~10°F cooler. Sow 3-ft row every couple weeks, rotate bale.
• Keep soil moist, well-drained.
• Organic mulch conserves moisture, suppresses weeds, keeps soil cool.
• Lettuce signals water need: wilting leaves → sprinkle anytime, even midday, to cool and slow transpiration.
• Hand-weed carefully—shallow roots.
• Plan garden so lettuce shaded by taller plants (tomatoes, corn) in summer heat to reduce bolting.

Pests and Diseases

• Aphids
• Earwigs
• Cutworms
• White Mold
• Woodchucks
• Rabbits

Harvest and Storage

• Harvest full size but just before maturity—young and tender.
• Pre-maturity: leaf lettuce—remove outer leaves, center grows. Butterhead/romaine—remove outer leaves, dig whole plant, or cut 1 inch above soil. Second harvest often possible. Crisphead—pick when center firm.
• Mature lettuce = bitter, woody, spoils fast. Check daily.
• Eventually cut whole plant at ground.
• Best: morning harvest before sun exposure.
• Refrigerate in loose plastic bag up to 10 days.

Recommended Varieties

• Crisphead: ‘King Crown’, ‘Mission’
• Cos (Romaine): ‘Wallop’, ‘Paris White Cos’
• Loose Heads: ‘Burpee Bibb’
• Red Leaf: ‘Red Sail’ (not for hot weather—red pigment absorbs heat).
• Container varieties: watch video for urban garden options.

Wit & Wisdom

• Lettuce is in the sunflower family.
• Wilted? Soak in ice water 15 minutes.
• Lettuce dinner = calming, stress-reducing.
• Embrace leafy greens! Health benefits of going green.

Recipes

• Lettuce Soup
• Peas Steamed in Lettuce
• Sunshine Salad

Cooking Notes

Lettuce = perfect salad base. Try eight great salad recipes for your harvest.