Cold hardiness & minimum temperature

Is Purple Vygie (Drosanthemum hispidum)cold hardy? Hardiness zone & min temp

Also called Purple Vygie, Hairy Dewflower, Purple Ice Plant.

More about purple vygie

About Purple Vygie

Drosanthemum hispidum · also called Purple Vygie, Hairy Dewflower · flowering

A distinctive, mat-forming succulent from South Africa, covered in fine hair-like papillae that give leaves a dewy shimmer and stems a fuzzy appearance — hence 'hairy dewflower'. In summer it produces a vivid display of bright pink to reddish-purple, daisy-like flowers. Drought-hardy to -7°C when dry, it suits gravel gardens, sunny banks, and containers in frost-light climates.

Cold limit: USDA 8-11 · RHS H2 (-7 to 35°C (dry cold only))

Watch for — Rot in cold, wet conditions: Wet cold — not dry cold — is the main threat. In climates with cold, wet winters, grow in containers that can be brought under frost-free glass, or ensure planting sites have near-perfect drainage. Wet soggy crowns rot rapidly below 4°C.

What purple vygie's hardiness rating actually means

Purple Vygie is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. 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 8-11 — 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

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Purple Vygie shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for purple vygie as it gets too cold:

Down to roughly about 1 to 5 °C it copes, especially if dry and sheltered.
A sustained hard frost collapses the top growth; whether it returns depends on whether the roots, crown or tubers froze.
Wet cold is far more lethal than dry cold for this plant — soggy, frozen soil is the usual killer.

Can purple vygie go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 8-11 or a frost-free UK microclimate.
In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter.
A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

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 purple vygie 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 purple vygie

Purple Vygie is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost.
Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse.
Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones.
Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.

Purple Vygie hardiness — frequently asked questions

Is purple vygie cold hardy?

Purple Vygie is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Borderline outdoors. In its mild end of USDA 8-11 (and sheltered UK gardens) purple vygie can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature purple vygie can survive?

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Purple Vygie shrugs off cold nights but a real, sustained freeze will kill it.

What hardiness zone is purple vygie?

Purple Vygie is rated USDA 8-11 and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can purple vygie survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 8-11 or a frost-free UK microclimate. In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter. A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

How do I protect purple vygie from frost?

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost. Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse. Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones. Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.