Broad bean · Gunpo, Gyeonggi-do, South Korea
When to plant broad beans in Gunpo
Main outdoor window
6-27 Feb
The window this page is built around.
Timed from last spring frost
3 April
In Gunpo, on your chosen risk.
Ready to pick
27 Apr - 17 May
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 Gunpo
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 overwintering
30 Jun - 21 Jul
Counting back 114 days from your first frost so the crop matures in time.
Sow direct
6-27 Feb
Eight weeks before your last frost.
Harvest
27 Apr - 17 May
Broad beans through the year
Against the frost risk in Gunpo
Why these dates
Sow in autumn in zones 7 and warmer for an early summer crop, or eight weeks before last frost in colder regions. Autumn sowings also dodge the worst of blackfly.
Survives -10C once established, and light snow cover helps rather than harms. Very young seedlings going into deep cold are the only real risk.
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. Broad beans are timed for direct sowing 8 weeks before it, and this page simply resolves those offsets against the frost date computed for Gunpo.
The median frost-free season here is 223 days, against 80 to 100 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Gunpo
Other vegetables to time
Growing broad beans in Gunpo
When should I plant broad beans in Gunpo?
Aim for 6-27 Feb in an average year. If you would rather not gamble on the weather, wait until 15 Feb - 8 Mar - by then frost has finished in nine years out of ten.
When will broad beans be ready to harvest in Gunpo?
Expect to start picking around 27 Apr - 17 May, based on 80 to 100 days to maturity from the planting date calculated for this location.
How much frost will broad beans tolerate?
Survives -10C once established, and light snow cover helps rather than harms. Very young seedlings going into deep cold are the only real risk.