Potato · Xinyang, Henan, China
When to plant potatoes in Xinyang
Main outdoor window
28 Feb - 14 Mar
The window this page is built around.
Timed from last spring frost
14 March
In Xinyang, on your chosen risk.
Ready to pick
9 May - 28 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 Xinyang
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
28 Feb - 14 Mar
Two weeks before your last frost.
Harvest
9 May - 28 Jun
Potatoes through the year
Against the frost risk in Xinyang
Why these dates
Plant two weeks before last frost so shoots emerge around the frost date. Earthing up buries vulnerable shoots and buys you a week of frost protection at a time.
Emerged foliage is blackened at -2C, though the plant usually regrows from the tuber with a yield penalty. Frost after emergence is the classic potato setback.
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. Potatoes are timed for direct sowing 2 weeks before it, and this page simply resolves those offsets against the frost date computed for Xinyang.
The median frost-free season here is 254 days, against 70 to 120 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Xinyang
Other vegetables to time
Growing potatoes in Xinyang
When should I plant potatoes in Xinyang?
Aim for 28 Feb - 14 Mar in an average year. If you would rather not gamble on the weather, wait until 12-26 Mar - by then frost has finished in nine years out of ten.
When will potatoes be ready to harvest in Xinyang?
Expect to start picking around 9 May - 28 Jun, based on 70 to 120 days to maturity from the planting date calculated for this location.
How much frost will potatoes tolerate?
Emerged foliage is blackened at -2C, though the plant usually regrows from the tuber with a yield penalty. Frost after emergence is the classic potato setback.