Winter squash · Kostroma, Kostroma Oblast, Russia
When to plant winter squashes in Kostroma
Main outdoor window
24 May - 7 Jun
The window this page is built around.
Timed from last spring frost
10 May
In Kostroma, on your chosen risk.
Ready to pick
12 Aug - 11 Sep
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 Kostroma
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.
Start indoors
19 Apr - 3 May
Three weeks before your last frost, under cover or on a windowsill.
Sow direct
24 May - 7 Jun
Two weeks after your last frost.
Plant out
24 May - 7 Jun
Two weeks after your last frost.
Harvest
12 Aug - 11 Sep
Winter squashes through the year
Against the frost risk in Kostroma
Why these dates
Work backwards: sow date plus days to maturity plus two weeks of curing must land before your first autumn frost. That constraint, not the spring date, is what rules this crop out in cold climates.
A light frost that kills the leaves will not ruin ripe fruit, but it stops any further ripening. Unripe squash does not store.
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. Winter squashes are timed from 3 weeks before that frost for an indoor start, with planting out 2 weeks after it, and this page simply resolves those offsets against the frost date computed for Kostroma.
The median frost-free season here is 149 days, against 80 to 110 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Kostroma
Other vegetables to time
Growing winter squashes in Kostroma
When should I plant winter squashes in Kostroma?
Aim for 24 May - 7 Jun in an average year. If you would rather not gamble on the weather, wait until 5-19 Jun - by then frost has finished in nine years out of ten.
When will winter squashes be ready to harvest in Kostroma?
Expect to start picking around 12 Aug - 11 Sep, based on 80 to 110 days to maturity from the planting date calculated for this location.
How much frost will winter squashes tolerate?
A light frost that kills the leaves will not ruin ripe fruit, but it stops any further ripening. Unripe squash does not store.