Cold hardiness & minimum temperature

Is Snow Pea (Pisum sativum var. macrocarpon)cold hardy? Hardiness zone & min temp

Also called Snow Pea, Mangetout, Chinese Pea Pod.

More about snow pea

About Snow Pea

Pisum sativum var. macrocarpon · also called Snow Pea, Mangetout · edible

Snow peas are cool-season climbers grown for their flat, edible pods harvested before the peas mature. Sow direct outdoors in early spring or autumn, provide a trellis, and keep well-watered. They prefer cool temperatures and will bolt in summer heat. Pods are ready 60–70 days from sowing and taste best picked young.

Cold limit: USDA 2–11 (cool-season annual) · RHS H4 (7–18°C (optimum); tolerates light frost to −2°C)

Watch for — Poor pod set / bolting: Temperatures above 21°C trigger bolting and poor pod fill. Sow at the correct season (early spring or autumn), mulch to keep roots cool, and harvest daily to extend cropping.

What snow pea's hardiness rating actually means

Hardiness works differently for snow pea: 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 2–11 (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 snow pea 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 snow pea 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 snow pea 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 snow pea

Snow Pea 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.

Snow Pea hardiness — frequently asked questions

Is snow pea cold hardy?

Hardiness works differently for snow pea: 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. Snow Pea is grown 2–11 (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 snow pea 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 snow pea?

Snow Pea is rated USDA 2–11 (cool-season annual) and RHS H4 — Hardy in an average winter across much of the temperate world.

Can snow pea 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 snow pea 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.