Coriander · Birmingham, England, United Kingdom
When to plant coriander in Birmingham
Main outdoor window
4-14 Apr
The window this page is built around.
Timed from last spring frost
18 April
In Birmingham, on your chosen risk.
Ready to pick
19 May - 13 Jun
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 Birmingham
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.
Sow for autumn
2-23 Aug
Counting back 84 days from your first frost so the crop matures in time.
Sow direct
4-14 Apr
Two weeks before your last frost.
Harvest
19 May - 13 Jun
Coriander through the year
Against the frost risk in Birmingham
Why these dates
Sow every two weeks from two weeks before last frost. The autumn sowing lasts far longer than any summer one, and in mild climates overwinters.
Takes -5C and grows happily in cool weather. Heat, not frost, is what ends a coriander plant.
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. Coriander are timed for direct sowing 2 weeks before it, and this page simply resolves those offsets against the frost date computed for Birmingham.
The median frost-free season here is 211 days, against 45 to 70 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Growing coriander in Birmingham
When should I plant coriander in Birmingham?
Aim for 4-14 Apr in an average year. If you would rather not gamble on the weather, wait until 29 Apr - 9 May - by then frost has finished in nine years out of ten.
When will coriander be ready to harvest in Birmingham?
Expect to start picking around 19 May - 13 Jun, based on 45 to 70 days to maturity from the planting date calculated for this location.
How much frost will coriander tolerate?
Takes -5C and grows happily in cool weather. Heat, not frost, is what ends a coriander plant.