Cold hardiness & minimum temperature

Is Bitter Melon (Bitter Gourd) (Momordica charantia)cold hardy? Hardiness zone & min temp

Also called bitter melon, bitter gourd, karela, goya.

More about bitter melon (bitter gourd)

About Bitter Melon (Bitter Gourd)

Momordica charantia · also called bitter melon, bitter gourd · edible

Bitter melon is a fast, frost-tender climbing cucurbit grown across Asia for its warty, intensely bitter fruit. Given heat, sun, and a sturdy trellis, vines sprawl quickly and fruit within a couple of months. A staple of stir-fries, curries, and stuffed dishes, it tolerates humidity well and is among the more vigorous warm-season vegetables once established.

Cold limit: USDA 10-12 (grown as a warm-season annual elsewhere) · RHS H1c (24-31°C)

Watch for — Cold damage: Vines stall below about 15°C and are killed by frost. Sow after all frost has passed and provide warmth early; transplant only into warm soil.

What bitter melon (bitter gourd)'s hardiness rating actually means

Hardiness works differently for bitter melon (bitter gourd): 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 H1c means: Warm-temperate — can summer outdoors but must come in well before the first frost. On the US scale that maps to USDA 10-12 (grown as a warm-season annual elsewhere) — 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 bitter melon (bitter gourd) 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 bitter melon (bitter gourd) 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 bitter melon (bitter gourd) can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Frost protection for borderline bitter melon (bitter gourd)

Bitter Melon (Bitter Gourd) 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.

Bitter Melon (Bitter Gourd) hardiness — frequently asked questions

Is bitter melon (bitter gourd) cold hardy?

Hardiness works differently for bitter melon (bitter gourd): 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. Bitter Melon (Bitter Gourd) is grown 10-12 (grown as a warm-season annual elsewhere); you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature bitter melon (bitter gourd) 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 bitter melon (bitter gourd)?

Bitter Melon (Bitter Gourd) is rated USDA 10-12 (grown as a warm-season annual elsewhere) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can bitter melon (bitter gourd) 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 bitter melon (bitter gourd) 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.