Leek · Springfield, Missouri, United States
When to plant leeks in Springfield
Main outdoor window
11 Apr - 2 May
The window this page is built around.
Timed from last spring frost
11 April
In Springfield, on your chosen risk.
Ready to pick
20 Jul - 9 Aug
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 Springfield
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
14 Feb - 7 Mar
Eight weeks before your last frost, under cover or on a windowsill.
Plant out
11 Apr - 2 May
Around your last frost.
Harvest
20 Jul - 9 Aug
Leeks through the year
Against the frost risk in Springfield
Why these dates
Sow indoors eight weeks before last frost, transplant around the frost date into deep holes. Harvest from autumn right through to spring as needed.
Hardy to -15C and often the only fresh vegetable still standing in midwinter.
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. Leeks are timed from 8 weeks before that frost for an indoor start, with planting out 0 weeks after it, and this page simply resolves those offsets against the frost date computed for Springfield.
The median frost-free season here is 201 days, against 100 to 120 days to maturity for this crop counted from planting out. That margin is what decides whether a late sowing is worth attempting.
Also in Springfield
Other vegetables to time
Growing leeks in Springfield
When should I plant leeks in Springfield?
Aim for 11 Apr - 2 May in an average year. If you would rather not gamble on the weather, wait until 22 Apr - 13 May - by then frost has finished in nine years out of ten.
When will leeks be ready to harvest in Springfield?
Expect to start picking around 20 Jul - 9 Aug, based on 100 to 120 days to maturity from the planting date calculated for this location.
How much frost will leeks tolerate?
Hardy to -15C and often the only fresh vegetable still standing in midwinter.