Courgette · Xuhui, Shanghai, China
When to plant courgettes in Xuhui
Main outdoor window
16-30 Mar
The window this page is built around.
Timed from last spring frost
2 March
In Xuhui, on your chosen risk.
Ready to pick
30 Apr - 15 May
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 Xuhui
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
9-23 Feb
Three weeks before your last frost, under cover or on a windowsill.
Sow direct
16-30 Mar
Two weeks after your last frost.
Plant out
16-30 Mar
Two weeks after your last frost.
Harvest
30 Apr - 15 May
Courgettes through the year
Against the frost risk in Xuhui
Why these dates
Two plants feed most households. A single sowing two weeks after last frost is usually enough; a July sowing gives cleaner, mildew-free fruit in long-season climates.
One light frost ends the plant. Because it crops so quickly, a courgette sown after all frost risk has passed still produces for months.
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. Courgettes 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 Xuhui.
The median frost-free season here is 287 days, against 45 to 60 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.
Also in Xuhui
Other vegetables to time
Growing courgettes in Xuhui
When should I plant courgettes in Xuhui?
Aim for 16-30 Mar in an average year. If you would rather not gamble on the weather, wait until 28 Mar - 11 Apr - by then frost has finished in nine years out of ten.
When will courgettes be ready to harvest in Xuhui?
Expect to start picking around 30 Apr - 15 May, based on 45 to 60 days to maturity from the planting date calculated for this location.
How much frost will courgettes tolerate?
One light frost ends the plant. Because it crops so quickly, a courgette sown after all frost risk has passed still produces for months.