Good King Henry · Shanghai, Shanghai, China
When to plant good king henry in Shanghai
Main outdoor window
9 Feb - 2 Mar
The window this page is built around.
Timed from last spring frost
2 March
In Shanghai, on your chosen risk.
Ready to pick
1 Apr - 30 Jun
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 Shanghai
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
9 Feb - 2 Mar
Three weeks before your last frost.
Harvest
1 Apr - 30 Jun
Good King Henry through the year
Against the frost risk in Shanghai
Why these dates
Extremely hardy and among the earliest greens available.
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. Good King Henry are timed for direct sowing 3 weeks before it, and this page simply resolves those offsets against the frost date computed for Shanghai.
Shanghai sits in zone 9a, which is milder than this crop wants, and a winter that never really arrives is its own problem. The dates below still describe the right time of year; the open question is survival rather than timing.
Do not expect a crop in the first year. A plant set out now should give its first worthwhile pick around year 2, and will then produce every year after that, which is what makes the planting decision worth getting right the first time.
Also in Shanghai
Other vegetables to time
Growing good king henry in Shanghai
When should I plant good king henry in Shanghai?
Aim for 9 Feb - 2 Mar in an average year. If you would rather not gamble on the weather, wait until 21 Feb - 14 Mar - by then frost has finished in nine years out of ten.
When will good king henry be ready to harvest in Shanghai?
Expect to start picking around 1 Apr - 30 Jun, based on 90 to 120 days to maturity from the planting date calculated for this location.
How much frost will good king henry tolerate?
Extremely hardy and among the earliest greens available.