Cold hardiness & minimum temperature

Is Pacifica Vinca (Catharanthus roseus 'Pacifica')cold hardy? Hardiness zone & min temp

Also called Pacifica Vinca, Annual Vinca, Madagascar Periwinkle, Pacifica Periwinkle.

More about pacifica vinca

About Pacifica Vinca

Catharanthus roseus 'Pacifica' · also called Pacifica Vinca, Annual Vinca · flowering

The Pacifica series is a compact, heat-tolerant cultivar group of Madagascar periwinkle producing an abundance of large, flat flowers in white, pink, red, and bicolour from late spring until frost. It thrives in full sun, tolerates drought once established, and resists deadheading — spent blooms drop cleanly. Highly toxic to pets and humans; all parts contain vinca alkaloids.

Cold limit: USDA 10–11 (perennial); grown as annual in zones 3–9 · RHS H1b (18–35°C; minimum 10°C)

What pacifica vinca's hardiness rating actually means

Hardiness works differently for pacifica vinca: 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 H1b means: Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season. On the US scale that maps to USDA 10–11 (perennial); grown as annual in zones 3–9 — 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 pacifica vinca 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 pacifica vinca 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 pacifica vinca can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Frost protection for borderline pacifica vinca

Pacifica Vinca 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.

Pacifica Vinca hardiness — frequently asked questions

Is pacifica vinca cold hardy?

Hardiness works differently for pacifica vinca: 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. Pacifica Vinca is grown 10–11 (perennial); grown as annual in zones 3–9; you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature pacifica vinca 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 pacifica vinca?

Pacifica Vinca is rated USDA 10–11 (perennial); grown as annual in zones 3–9 and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can pacifica vinca 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 pacifica vinca 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.