Canterbury bells · Hŭngnam, South Hamgyong, North Korea
When to sow canterbury bells in Hŭngnam
Main outdoor window
1-29 Jun
The window this page is built around.
Timed from last spring frost
20 April
In Hŭngnam, on your chosen risk.
Ready to pick
1 Jun - 31 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 Hŭngnam
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
1-29 Jun
Six weeks after your last frost.
Move to final position
7 Sep - 5 Oct
20 weeks after your last frost.
In flower
1 Jun - 31 Jul
Canterbury bells through the year
Against the frost risk in Hŭngnam
Why these dates
Sow on the surface in early summer, six weeks after the last frost, and move the rosettes to their final position in autumn. Flowers the following June for about five weeks. Deadheading the main spike brings a lighter second flush from the side shoots.
Hardy to about -18C as a rosette, though it dislikes a wet winter and is safer on free-draining ground or with a mulch of grit around the crown.
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. Canterbury bells are timed with planting out 20 weeks after it, and this page simply resolves those offsets against the frost date computed for Hŭngnam.
Hardiness is not the obstacle here. Hŭngnam is zone 6a, comfortably inside the range this crop is rated for, so an established plant should come through an average winter without protection.
This is a two-season crop, so the dates above describe a sowing in one year and a flowering in the next. The plant spends the winter in the ground as a small rosette, which is why the frost-free season in Hŭngnam does not limit it the way it would limit a tomato: it is not trying to finish before the cold arrives, it is trying to be well enough rooted to sit through it. Sowing too late is the real risk, because a plant that goes into winter undersized often fails to flower at all the following year.
Also in Hŭngnam
Other flowers to time
Growing canterbury bells in Hŭngnam
When should I plant canterbury bells in Hŭngnam?
Aim for 1-29 Jun in an average year. If you would rather not gamble on the weather, wait until 7 Jun - 5 Jul - by then frost has finished in nine years out of ten.
When will canterbury bells be ready to harvest in Hŭngnam?
Expect to start picking around 1 Jun - 31 Jul, based on 335 to 385 days to maturity from the planting date calculated for this location.
How much frost will canterbury bells tolerate?
Hardy to about -18C as a rosette, though it dislikes a wet winter and is safer on free-draining ground or with a mulch of grit around the crown.