Cold hardiness & minimum temperature

Is Greater Spearwort (Ranunculus lingua)cold hardy? Hardiness zone & min temp

Also called Greater Spearwort, Spearwort.

More about greater spearwort

About Greater Spearwort

Ranunculus lingua · also called Greater Spearwort, Spearwort · flowering

Greater Spearwort is a tall, stately native European aquatic perennial with bold lance-shaped leaves and large, bright yellow buttercup flowers from late spring to midsummer. Ideal for deeper pond margins and wildlife ponds, where its vigour provides good cover for aquatic fauna. All Ranunculus contain acrid compounds irritating to skin and toxic if ingested.

Cold limit: USDA 4–9 · RHS H7 (-20–28°C)

What greater spearwort's hardiness rating actually means

Yes — greater spearwort is genuinely cold hardy. Rated RHS H7 and USDA 4–9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H7 means: Hardy in the severest European continental winters. On the US scale that maps to USDA 4–9 — 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 below about −20 °C. Greater Spearwort is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for greater spearwort as it gets too cold:

It tolerates winter lows to about −20 °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 greater spearwort go outside or overwinter — and where?

Plant it out within USDA 4–9 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 greater spearwort can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Greater Spearwort hardiness — frequently asked questions

Is greater spearwort cold hardy?

Yes — greater spearwort is genuinely cold hardy. Rated RHS H7 and USDA 4–9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Greater Spearwort is hardy across USDA 4–9; 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 greater spearwort can survive?

Minimum survivable temperature is roughly below about −20 °C. Greater Spearwort is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is greater spearwort?

Greater Spearwort is rated USDA 4–9 and RHS H7 — Hardy in the severest European continental winters.

Can greater spearwort survive winter outside?

Plant it out within USDA 4–9 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.

What happens to greater spearwort below its minimum temperature?

It tolerates winter lows to about −20 °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.