Cold hardiness & minimum temperature

Is Dionaea muscipula 'Akai Ryu' (Dionaea muscipula 'Akai Ryu')cold hardy? Hardiness zone & min temp

Also called Red Dragon flytrap.

More about dionaea muscipula 'akai ryu'

About Dionaea muscipula 'Akai Ryu'

Dionaea muscipula 'Akai Ryu' · also called Red Dragon flytrap · tropical

Dionaea muscipula 'Akai Ryu' (Red Dragon) is a striking all-red Venus flytrap cultivar, deep maroon throughout leaves and traps rather than just the trap interior. It is a temperate bog plant requiring intense sun to hold its colour, pure water, permanently wet acidic peat, and a real winter dormancy. Slightly slower than green forms but exceptionally ornamental.

Cold limit: USDA 7-10 (requires a cold winter dormancy near 2-10°C) · RHS H4 (-5-35°C)

Watch for — No winter dormancy: Like all flytraps it needs 3-4 months of cold rest near 2-10°C; skipping it leads to decline and death.

What dionaea muscipula 'akai ryu''s hardiness rating actually means

Yes — dionaea muscipula 'akai ryu' is genuinely cold hardy. Rated RHS H4 and USDA 7-10 (requires a cold winter dormancy near 2-10°C), it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H4 means: Hardy in an average winter across much of the temperate world. On the US scale that maps to USDA 7-10 (requires a cold winter dormancy near 2-10°C) — 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 −10 to −5 °C. Dionaea muscipula 'Akai Ryu' is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for dionaea muscipula 'akai ryu' as it gets too cold:

It tolerates winter lows to about −10 to −5 °C once established.
Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root.
First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.

Can dionaea muscipula 'akai ryu' go outside or overwinter — and where?

Plant it out within USDA 7-10 (requires a cold winter dormancy near 2-10°C) and it overwinters with little or no help.
It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy.
The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

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 'akai ryu' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H4 figure above.

Frost protection for borderline dionaea muscipula 'akai ryu'

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

At the cold edge of its range, mulch the root zone in late autumn to buffer the deepest freezes.
Protect container specimens — pots freeze through far faster than open ground, costing roughly a zone of hardiness.
Shelter new growth from late spring frosts with fleece if a hard night is forecast.

Dionaea muscipula 'Akai Ryu' hardiness — frequently asked questions

Is dionaea muscipula 'akai ryu' cold hardy?

Yes — dionaea muscipula 'akai ryu' is genuinely cold hardy. Rated RHS H4 and USDA 7-10 (requires a cold winter dormancy near 2-10°C), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Dionaea muscipula 'Akai Ryu' is hardy across USDA 7-10 (requires a cold winter dormancy near 2-10°C); it belongs in the ground or a frost-proof container, not on a windowsill, and many types actively need a cold winter to perform.

What is the minimum temperature dionaea muscipula 'akai ryu' can survive?

Minimum survivable temperature is roughly about −10 to −5 °C. Dionaea muscipula 'Akai Ryu' is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is dionaea muscipula 'akai ryu'?

Dionaea muscipula 'Akai Ryu' is rated USDA 7-10 (requires a cold winter dormancy near 2-10°C) and RHS H4 — Hardy in an average winter across much of the temperate world.

Can dionaea muscipula 'akai ryu' survive winter outside?

Plant it out within USDA 7-10 (requires a cold winter dormancy near 2-10°C) and it overwinters with little or no help. It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy. The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

How do I protect dionaea muscipula 'akai ryu' from frost?

At the cold edge of its range, mulch the root zone in late autumn to buffer the deepest freezes. Protect container specimens — pots freeze through far faster than open ground, costing roughly a zone of hardiness. Shelter new growth from late spring frosts with fleece if a hard night is forecast.