Yam · Acheng, Heilongjiang, China
When to plant yams in Acheng
Main outdoor window
13 May - 10 Jun
The window this page is built around.
Timed from last spring frost
29 April
In Acheng, on your chosen risk.
Ready to pick
1 Oct - 31 Dec
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 Acheng
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.
Plant tubers
13 May - 10 Jun
Two weeks after your last frost.
Harvest
1 Oct - 31 Dec
Yams through the year
Against the frost risk in Acheng
Why these dates
No frost tolerance whatsoever.
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. Yams are timed with planting out 2 weeks after it, and this page simply resolves those offsets against the frost date computed for Acheng.
Acheng sits in zone 4a, which is colder than this crop is rated for, so it will need winter protection or a container that can be moved under cover. The dates below still describe the right time of year; the open question is survival rather than timing.
The median frost-free season here is 159 days, against 240 to 300 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Acheng
Other vegetables to time
Growing yams in Acheng
When should I plant yams in Acheng?
Aim for 13 May - 10 Jun in an average year. If you would rather not gamble on the weather, wait until 22 May - 19 Jun - by then frost has finished in nine years out of ten.
When will yams be ready to harvest in Acheng?
Expect to start picking around 1 Oct - 31 Dec, based on 240 to 300 days to maturity from the planting date calculated for this location.
How much frost will yams tolerate?
No frost tolerance whatsoever.