Growli

Cold hardiness & minimum temperature

Is Bacopa 'Snowtopia' (Sutera cordata 'Snowtopia')cold hardy? Hardiness zone & min temp

Also called Snowtopia Bacopa, White Trailing Bacopa.

More about bacopa 'snowtopia'

About Bacopa 'Snowtopia'

Sutera cordata 'Snowtopia' · also called Snowtopia Bacopa, White Trailing Bacopa · flowering

'Snowtopia' is a trailing Sutera (garden bacopa) producing a continuous haze of small five-petalled white flowers over small green leaves from spring to frost. A go-to spiller for hanging baskets and mixed containers, it likes sun to part shade, even moisture and is self-cleaning, dropping spent blooms without deadheading.

Cold limit: USDA 9-11 (grown as a frost-tender annual in most US zones) · RHS H2 (10-26°C)

What bacopa 'snowtopia''s hardiness rating actually means

Bacopa 'Snowtopia' 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 9-11 (grown as a frost-tender annual in most US zones) — 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. Bacopa 'Snowtopia' shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for bacopa 'snowtopia' as it gets too cold:

Can bacopa 'snowtopia' go outside or overwinter — and where?

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 bacopa 'snowtopia' 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 bacopa 'snowtopia'

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

Bacopa 'Snowtopia' hardiness — frequently asked questions

Is bacopa 'snowtopia' cold hardy?

Bacopa 'Snowtopia' 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 9-11 (grown as a frost-tender annual in most US zones) (and sheltered UK gardens) bacopa 'snowtopia' can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature bacopa 'snowtopia' can survive?

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

What hardiness zone is bacopa 'snowtopia'?

Bacopa 'Snowtopia' is rated USDA 9-11 (grown as a frost-tender annual in most US zones) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can bacopa 'snowtopia' survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (grown as a frost-tender annual in most US zones) 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 bacopa 'snowtopia' 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.

Keep reading