Broccoli · Wŏnsan, Kangwŏn-do, North Korea
When to plant broccoli in Wŏnsan
Main outdoor window
26 Mar - 16 Apr
The window this page is built around.
Timed from last spring frost
9 April
In Wŏnsan, on your chosen risk.
Ready to pick
25 May - 24 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 Wŏnsan
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
19 Feb - 12 Mar
Seven weeks before your last frost, under cover or on a windowsill.
Sow for autumn
30 Jun - 21 Jul
Counting back 104 days from your first frost so the crop matures in time.
Plant out
26 Mar - 16 Apr
Two weeks before your last frost.
Harvest
25 May - 24 Jun
Broccoli through the year
Against the frost risk in Wŏnsan
Why these dates
Aim to have heads maturing before summer heat or after it. A midsummer maturity date produces small, loose, bitter heads no matter how well you grow the plant.
Transplants take -6C. Purple sprouting types are far hardier and are grown deliberately through winter for a spring crop.
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. Broccoli are timed from 7 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 Wŏnsan.
The median frost-free season here is 207 days, against 60 to 90 days to maturity for this crop counted from planting out. That margin is what decides whether a late sowing is worth attempting.
Also in Wŏnsan
Other vegetables to time
Growing broccoli in Wŏnsan
When should I plant broccoli in Wŏnsan?
Aim for 26 Mar - 16 Apr in an average year. If you would rather not gamble on the weather, wait until 2-23 Apr - by then frost has finished in nine years out of ten.
When will broccoli be ready to harvest in Wŏnsan?
Expect to start picking around 25 May - 24 Jun, based on 60 to 90 days to maturity from the planting date calculated for this location.
How much frost will broccoli tolerate?
Transplants take -6C. Purple sprouting types are far hardier and are grown deliberately through winter for a spring crop.