Oats · Hamhŭng, South Hamgyong, North Korea
When to plant oats in Hamhŭng
Main outdoor window
23 Mar - 13 Apr
The window this page is built around.
Timed from last spring frost
20 April
In Hamhŭng, on your chosen risk.
Ready to pick
1-31 Jul
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 Hamhŭng
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 direct
23 Mar - 13 Apr
Four weeks before your last frost.
Harvest
1-31 Jul
Oats through the year
Against the frost risk in Hamhŭng
Why these dates
Sow very early in spring for grain. Sown in late summer instead, oats make excellent ground cover that winter-kills cleanly and leaves an easy seedbed in spring.
Seedlings take -7C. Oats sown as a cover crop are deliberately killed by frost around -8C, which is the point - the residue mulches the bed without needing removal.
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. Oats are timed for direct sowing 4 weeks before it, and this page simply resolves those offsets against the frost date computed for Hamhŭng.
The median frost-free season here is 185 days, against 100 to 130 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Hamhŭng
Other grains to time
Growing oats in Hamhŭng
When should I plant oats in Hamhŭng?
Aim for 23 Mar - 13 Apr in an average year. If you would rather not gamble on the weather, wait until 29 Mar - 19 Apr - by then frost has finished in nine years out of ten.
When will oats be ready to harvest in Hamhŭng?
Expect to start picking around 1-31 Jul, based on 100 to 130 days to maturity from the planting date calculated for this location.
How much frost will oats tolerate?
Seedlings take -7C. Oats sown as a cover crop are deliberately killed by frost around -8C, which is the point - the residue mulches the bed without needing removal.