Cold hardiness & minimum temperature

Is Chrysanthemum Greens (Glebionis coronaria)cold hardy? Hardiness zone & min temp

Also called chrysanthemum greens, shungiku, edible chrysanthemum, garland chrysanthemum.

More about chrysanthemum greens

About Chrysanthemum Greens

Glebionis coronaria · also called chrysanthemum greens, shungiku · edible

Chrysanthemum greens (Glebionis coronaria, shungiku) are an annual leafy herb in the daisy family grown for their aromatic, slightly bitter young leaves and shoots used in East Asian cooking. Fast and cool-season, they bolt readily in heat into daisy-like yellow flowers. Harvest tender tips young and often; flavour turns strong and resinous once plants begin to flower.

Cold limit: USDA 2-11 (grown as a cool-season annual) · RHS H3 (10-22°C)

What chrysanthemum greens's hardiness rating actually means

Hardiness works differently for chrysanthemum greens: it is grown as a seasonal crop, not overwintered. The question is not "what zone" but "how long is your frost-free growing window". Its RHS rating of H3 means: Half-hardy — comes through mild UK winters outside but is killed by a hard freeze. On the US scale that maps to USDA 2-11 (grown as a cool-season annual) — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

As an annual crop, its "minimum temperature" is the first hard frost — that is the end of the plant's life, not a survivable low. Many types are also damaged by light frost (around 0 °C).

Concretely, for chrysanthemum greens as it gets too cold:

Light frost (around 0 to −2 °C) damages or kills tender summer crops outright; cold-hardy types take a few degrees of frost.
The plant does not "survive winter" — its life cycle simply ends, by design, when frost arrives or it finishes cropping.
A surprise late spring frost can also kill young transplants set out too early, before the season even starts.

Can chrysanthemum greens go outside or overwinter — and where?

Time it to your frost dates: sow or plant out after the last spring frost, and aim to harvest before the first autumn frost.
In short-season zones, start it indoors or under cover to stretch the effective growing window.
Hardier crops in this group can be sown for an autumn or overwintered harvest in mild zones — check the specific crop.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when chrysanthemum greens can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H3 figure above.

Frost protection for borderline chrysanthemum greens

Chrysanthemum Greens is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Use fleece, cloches or a cold frame at each end of the season to dodge a borderline frost and add growing weeks.
Have row cover ready for an unexpected late spring or early autumn frost.
Know your local last- and first-frost dates and count back the crop’s days-to-maturity to schedule the sowing.

Chrysanthemum Greens hardiness — frequently asked questions

Is chrysanthemum greens cold hardy?

Hardiness works differently for chrysanthemum greens: it is grown as a seasonal crop, not overwintered. The question is not "what zone" but "how long is your frost-free growing window". A seasonal crop, not a perennial. Chrysanthemum Greens is grown 2-11 (grown as a cool-season annual); you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature chrysanthemum greens can survive?

As an annual crop, its "minimum temperature" is the first hard frost — that is the end of the plant's life, not a survivable low. Many types are also damaged by light frost (around 0 °C).

What hardiness zone is chrysanthemum greens?

Chrysanthemum Greens is rated USDA 2-11 (grown as a cool-season annual) and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can chrysanthemum greens survive winter outside?

Time it to your frost dates: sow or plant out after the last spring frost, and aim to harvest before the first autumn frost. In short-season zones, start it indoors or under cover to stretch the effective growing window. Hardier crops in this group can be sown for an autumn or overwintered harvest in mild zones — check the specific crop.

How do I protect chrysanthemum greens from frost?

Use fleece, cloches or a cold frame at each end of the season to dodge a borderline frost and add growing weeks. Have row cover ready for an unexpected late spring or early autumn frost. Know your local last- and first-frost dates and count back the crop’s days-to-maturity to schedule the sowing.