Cold hardiness & minimum temperature

Is Dionaea muscipula 'Cupped Trap' (Dionaea muscipula 'Cupped Trap')cold hardy? Hardiness zone & min temp

Also called Cupped Trap Venus Flytrap, Bowl Flytrap.

More about dionaea muscipula 'cupped trap'

About Dionaea muscipula 'Cupped Trap'

Dionaea muscipula 'Cupped Trap' · also called Cupped Trap Venus Flytrap, Bowl Flytrap · houseplant

'Cupped Trap' is a Venus flytrap cultivar whose trap lobes fuse into a deep bowl or goblet shape rather than the usual jaw. It needs blazing direct sun, permanently wet mineral-free media, and a cold winter dormancy. Feed it insects, never fertiliser, and water only with rain, distilled or RO water.

Cold limit: USDA 6-8 outdoors with protection; commonly grown as a windowsill/cold-frame plant elsewhere · RHS H3 (21-35°C summer; 2-10°C winter dormancy)

Watch for — No winter dormancy: Kept warm and lit year-round, the plant exhausts itself and weakens or dies. Give a cool 2-10°C rest for 3-4 months each winter.

What dionaea muscipula 'cupped trap''s hardiness rating actually means

Dionaea muscipula 'Cupped Trap' is half-hardy (RHS H3). 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 H3 means: Half-hardy — comes through mild UK winters outside but is killed by a hard freeze. On the US scale that maps to USDA 6-8 outdoors with protection; commonly grown as a windowsill/cold-frame plant 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

Minimum survivable temperature is roughly about −5 to 1 °C — a light, short frost only. Dionaea muscipula 'Cupped Trap' shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for dionaea muscipula 'cupped trap' as it gets too cold:

Down to roughly about −5 to 1 °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 dionaea muscipula 'cupped trap' go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 6-8 outdoors with protection; commonly grown as a windowsill/cold-frame plant elsewhere 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 dionaea muscipula 'cupped trap' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H3 figure above.

Frost protection for borderline dionaea muscipula 'cupped trap'

Dionaea muscipula 'Cupped Trap' 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.

Dionaea muscipula 'Cupped Trap' hardiness — frequently asked questions

Is dionaea muscipula 'cupped trap' cold hardy?

Dionaea muscipula 'Cupped Trap' is half-hardy (RHS H3). 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 6-8 outdoors with protection; commonly grown as a windowsill/cold-frame plant elsewhere (and sheltered UK gardens) dionaea muscipula 'cupped trap' can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature dionaea muscipula 'cupped trap' can survive?

Minimum survivable temperature is roughly about −5 to 1 °C — a light, short frost only. Dionaea muscipula 'Cupped Trap' shrugs off cold nights but a real, sustained freeze will kill it.

What hardiness zone is dionaea muscipula 'cupped trap'?

Dionaea muscipula 'Cupped Trap' is rated USDA 6-8 outdoors with protection; commonly grown as a windowsill/cold-frame plant elsewhere and RHS H3 — Half-hardy — comes through mild UK winters outside but is killed by a hard freeze.

Can dionaea muscipula 'cupped trap' survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 6-8 outdoors with protection; commonly grown as a windowsill/cold-frame plant elsewhere 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 dionaea muscipula 'cupped trap' 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.