Good King Henry · Philadelphia, Pennsylvania, United States
When to plant good king henry in Philadelphia
Main outdoor window
24 Mar - 14 Apr
The window this page is built around.
Timed from last spring frost
14 April
In Philadelphia, 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 Philadelphia
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
24 Mar - 14 Apr
Three weeks before your last frost.
Harvest
1 Apr - 30 Jun
Good King Henry through the year
Against the frost risk in Philadelphia
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 Philadelphia.
Hardiness is not the obstacle here. Philadelphia is zone 7a, comfortably inside the range this crop is rated for, so an established plant should come through an average winter without protection.
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 Philadelphia
Other vegetables to time
Growing good king henry in Philadelphia
When should I plant good king henry in Philadelphia?
Aim for 24 Mar - 14 Apr in an average year. If you would rather not gamble on the weather, wait until 2-23 Apr - by then frost has finished in nine years out of ten.
When will good king henry be ready to harvest in Philadelphia?
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.