Cold hardiness & minimum temperature

Is Pink Surprise calendula (Calendula officinalis 'Pink Surprise')cold hardy? Hardiness zone & min temp

Also called Pink Surprise calendula, Pink Surprise pot marigold, Pink Surprise marigold.

More about pink surprise calendula

About Pink Surprise calendula

Calendula officinalis 'Pink Surprise' · also called Pink Surprise calendula, Pink Surprise pot marigold · flowering

A distinctive Calendula officinalis cultivar producing fully double, salmon-pink to apricot blooms with a touch of orange on bushy, aromatic plants. A cool-season annual that thrives in full sun with poor to moderately fertile, free-draining soil. Long flowering season from spring to autumn with regular deadheading; excellent for cutting and pollinator gardens.

Cold limit: USDA 8–11 as short-lived perennial; annual in zones 2–7 · RHS H4 (7–20 °C optimal; tolerates light frost to −5 °C)

What pink surprise calendula's hardiness rating actually means

Hardiness works differently for pink surprise calendula: 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 H4 means: Hardy in an average winter across much of the temperate world. On the US scale that maps to USDA 8–11 as short-lived perennial; annual in zones 2–7 — 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 pink surprise calendula 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 pink surprise calendula 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 pink surprise calendula can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H4 figure above.

Frost protection for borderline pink surprise calendula

Pink Surprise calendula 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.

Pink Surprise calendula hardiness — frequently asked questions

Is pink surprise calendula cold hardy?

Hardiness works differently for pink surprise calendula: 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. Pink Surprise calendula is grown 8–11 as short-lived perennial; annual in zones 2–7; you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature pink surprise calendula 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 pink surprise calendula?

Pink Surprise calendula is rated USDA 8–11 as short-lived perennial; annual in zones 2–7 and RHS H4 — Hardy in an average winter across much of the temperate world.

Can pink surprise calendula 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 pink surprise calendula 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.