Cold hardiness & minimum temperature

Is Popcorn (Zea mays var. everta 'Strawberry Popcorn')cold hardy? Hardiness zone & min temp

Also called strawberry popcorn, ornamental popcorn.

More about popcorn

About Popcorn

Zea mays var. everta 'Strawberry Popcorn' · also called strawberry popcorn, ornamental popcorn · edible

Popcorn is a flint-type maize whose hard kernels burst when heated. 'Strawberry Popcorn' is a compact, ornamental variety with squat ruby-red cobs that double as decoration and snack. Grow like sweetcorn but leave cobs on the plant until fully ripe and dry, then cure further indoors before the kernels will pop reliably.

Cold limit: USDA 3-11 (frost-tender summer annual; needs a long season) · RHS H2 (16-32°C)

Watch for — Short-season failure to ripen: Popcorn needs a long warm season. In cooler regions start early under cover so cobs mature and dry before frost.

What popcorn's hardiness rating actually means

Hardiness works differently for popcorn: 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 H2 means: Tender — survives a frost-free greenhouse or a very mild, sheltered spot. On the US scale that maps to USDA 3-11 (frost-tender summer annual; needs a long season) — 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 popcorn 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 popcorn 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 popcorn can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H2 figure above.

Frost protection for borderline popcorn

Popcorn 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.

Popcorn hardiness — frequently asked questions

Is popcorn cold hardy?

Hardiness works differently for popcorn: 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. Popcorn is grown 3-11 (frost-tender summer annual; needs a long season); you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature popcorn 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 popcorn?

Popcorn is rated USDA 3-11 (frost-tender summer annual; needs a long season) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can popcorn 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 popcorn 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.