Planting Romaine Lettuce
Romaine Lettuce is a cool season vegetable in the Asteraceae family. Getting the timing right is the difference between a strong stand and a disappointing one, so the windows below are given relative to your own last spring frost and first fall frost rather than a generic calendar date. Look up your local frost dates and count back or forward from there.
Romaine Lettuce is started indoors 4–6 weeks before your last spring frost date, giving seedlings a head start before they move outside.
Transplant young plants outdoors 1–3 weeks before your last frost — Romaine Lettuce tolerates cool conditions and benefits from an early start.
You can sow Romaine Lettuce directly into the garden 2–4 weeks before your last frost.
For a fall crop, sow 8–10 weeks before your first fall frost so plants mature as the weather cools.
Romaine Lettuce can be grown by direct sowing, starting indoors, and transplanting. Starting indoors gives the longest, most controlled season, while direct sowing is simplest where the season is long enough.
Spacing and Planting Depth
Give Romaine Lettuce room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 10 inches |
|---|---|
| Row spacing | 12 inches |
| Plants per sq ft | 1.2 |
| Planting depth | 0.125 inches |
| Sun requirement | Partial sun |
Days to Maturity
Romaine Lettuce reaches maturity in 55–70 days from transplant. Once ready, plants continue producing for approximately 14 days.
For a continuous harvest, sow a new batch every 14 days. Use the succession planting scheduler →
Romaine Lettuce is ready to harvest after about 63 days. Picking regularly over the roughly 14-day harvest window keeps plants productive and encourages a longer pick. Harvest before summer heat or, for fall crops, before a hard freeze, to keep quality high.
Conditions and Care
As a cool-season vegetable, Romaine Lettuce does its best growing in the cooler weather of spring and fall and tends to bolt or turn bitter in summer heat. It is half-hardy — it withstands light frost but should be protected from a hard freeze.
Romaine Lettuce grows well in partial sun and tolerates some afternoon shade, which can help slow bolting in warm weather. Sow seed about 0.125 inches deep — small seed is sown shallow and barely covered, then keep the soil evenly moist until seedlings establish.
Romaine Lettuce belongs to the Asteraceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Because it matures relatively quickly, Romaine Lettuce rewards succession sowing: small, repeated plantings keep a steady supply coming rather than one short glut.
Companion Plants
Pairing Romaine Lettuce with the right neighbors can improve growth and deter pests; a few combinations are best avoided.
Grows well with: Carrots, Radish, Strawberry
Keep away from: Celery