Iceberg lettuce · Washington, District of Columbia, United States
When to plant iceberg lettuce in Washington
Main outdoor window
13-27 Mar
The window this page is built around.
Timed from last spring frost
3 April
In Washington, on your chosen risk.
Ready to pick
1 Jun - 30 Sep
If you plant at the start of the window.
The average last frost. Half of all years are later than this.
Step by step in Washington
Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.
Start indoors
20 Feb - 6 Mar
Six weeks before your last frost, under cover or on a windowsill.
Sow direct
13-27 Mar
Three weeks before your last frost.
Transplant
20 Mar - 3 Apr
Two weeks before your last frost.
Harvest
1 Jun - 30 Sep
Iceberg lettuce through the year
Against the frost risk in Washington
Why these dates
Start indoors six weeks before the last frost and plant out two weeks before. A check to growth at any point gives you a loose head rather than a dense one.
Takes around -3C. The long season means a late sowing can be caught by the first autumn frost before it has hearted.
Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Iceberg lettuce are timed from 6 weeks before that frost for an indoor start, with planting out 2 weeks before it, and this page simply resolves those offsets against the frost date computed for Washington.
The median frost-free season here is 221 days, against 70 to 85 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Nearby
Iceberg lettuce in places close by
Also in Washington
Other vegetables to time
Growing iceberg lettuce in Washington
When should I plant iceberg lettuce in Washington?
Aim for 13-27 Mar in an average year. If you would rather not gamble on the weather, wait until 23 Mar - 6 Apr - by then frost has finished in nine years out of ten.
When will iceberg lettuce be ready to harvest in Washington?
Expect to start picking around 1 Jun - 30 Sep, based on 70 to 85 days to maturity from the planting date calculated for this location.
How much frost will iceberg lettuce tolerate?
Takes around -3C. The long season means a late sowing can be caught by the first autumn frost before it has hearted.