Cowpea · Yokosuka, Kanagawa, Japan
When to plant cowpeas in Yokosuka
Main outdoor window
15 Apr - 6 May
The window this page is built around.
Timed from last spring frost
1 April
In Yokosuka, on your chosen risk.
Ready to pick
24 Jun - 24 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 Yokosuka
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
15 Apr - 6 May
Two weeks after your last frost.
Harvest
24 Jun - 24 Jul
Cowpeas through the year
Against the frost risk in Yokosuka
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 Yokosuka.
The median frost-free season here is 247 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 Yokosuka
Other grains to time
Growing cowpeas in Yokosuka
When should I plant cowpeas in Yokosuka?
Aim for 15 Apr - 6 May in an average year. If you would rather not gamble on the weather, wait until 23 Apr - 14 May - by then frost has finished in nine years out of ten.
When will cowpeas be ready to harvest in Yokosuka?
Expect to start picking around 24 Jun - 24 Jul, 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.