Cold hardiness & minimum temperature

Is Moon and Stars Watermelon (Citrullus lanatus 'Moon and Stars')cold hardy? Hardiness zone & min temp

Also called Moon and Stars watermelon, Cherokee Moon and Stars.

More about moon and stars watermelon

About Moon and Stars Watermelon

Citrullus lanatus 'Moon and Stars' · also called Moon and Stars watermelon, Cherokee Moon and Stars · edible

Moon and Stars is a striking heirloom watermelon (Citrullus lanatus) whose dark rind is dappled with one large yellow 'moon' and many small 'star' speckles, and whose leaves are flecked too. Once nearly lost, it was famously rediscovered in the 1980s. The large, sweet red-fleshed fruit needs full sun, warm soil and a long 90-100 day season.

Cold limit: USDA 3-11 (warm-season annual) · RHS H1c (21-35°C)

What moon and stars watermelon's hardiness rating actually means

Hardiness works differently for moon and stars watermelon: 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 3-11 (warm-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 moon and stars watermelon 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 moon and stars watermelon 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 moon and stars watermelon 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 moon and stars watermelon

Moon and Stars Watermelon 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.

Moon and Stars Watermelon hardiness — frequently asked questions

Is moon and stars watermelon cold hardy?

Hardiness works differently for moon and stars watermelon: 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. Moon and Stars Watermelon is grown 3-11 (warm-season annual); you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature moon and stars watermelon 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 moon and stars watermelon?

Moon and Stars Watermelon is rated USDA 3-11 (warm-season annual) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can moon and stars watermelon 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 moon and stars watermelon 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.