Cowpea · Shangzhi, Heilongjiang, China
When to plant cowpeas in Shangzhi
Main outdoor window
20 May - 10 Jun
The window this page is built around.
Timed from last spring frost
6 May
In Shangzhi, on your chosen risk.
Ready to pick
29 Jul - 28 Aug
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 Shangzhi
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
20 May - 10 Jun
Two weeks after your last frost.
Harvest
29 Jul - 28 Aug
Cowpeas through the year
Against the frost risk in Shangzhi
Why these dates
Sow two weeks after the last frost once soil is genuinely warm. Cowpeas grow fast enough in heat to be sown as a second crop after an early harvest.
Tender at 0C, with no useful frost tolerance at either end.
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. Cowpeas are timed for direct sowing 2 weeks after it, and this page simply resolves those offsets against the frost date computed for Shangzhi.
The median frost-free season here is 151 days, against 70 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 Shangzhi
Other grains to time
Growing cowpeas in Shangzhi
When should I plant cowpeas in Shangzhi?
Aim for 20 May - 10 Jun in an average year. If you would rather not gamble on the weather, wait until 24 May - 14 Jun - by then frost has finished in nine years out of ten.
When will cowpeas be ready to harvest in Shangzhi?
Expect to start picking around 29 Jul - 28 Aug, based on 70 to 100 days to maturity from the planting date calculated for this location.
How much frost will cowpeas tolerate?
Tender at 0C, with no useful frost tolerance at either end.