Cold hardiness & minimum temperature

Is Common Bird's-foot Trefoil (Lotus corniculatus)cold hardy? Hardiness zone & min temp

Also called Common Bird's-foot Trefoil, Bird's-foot Trefoil, Eggs and Bacon.

More about common bird's-foot trefoil

About Common Bird's-foot Trefoil

Lotus corniculatus · also called Common Bird's-foot Trefoil, Bird's-foot Trefoil · flowering

Lotus corniculatus is a low-growing perennial wildflower native to grasslands across Europe, Asia, and North Africa, widely naturalised in North America. It thrives in full sun on poor, well-drained, low-nitrogen soils — excessive fertility encourages leafy growth at the expense of flowers. As a legume it fixes atmospheric nitrogen through root nodal bacteria, so avoid enriching the soil. The plant contains cyanogenic glycosides (primarily lotaustralin) and is considered mildly toxic to pets if ingested in quantity.

Cold limit: USDA 4-9 · RHS H7 (-25 to 30°C)

What common bird's-foot trefoil's hardiness rating actually means

Yes — common bird's-foot trefoil 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. Common Bird's-foot Trefoil is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for common bird's-foot trefoil 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 common bird's-foot trefoil 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 common bird's-foot trefoil can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Common Bird's-foot Trefoil hardiness — frequently asked questions

Is common bird's-foot trefoil cold hardy?

Yes — common bird's-foot trefoil 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. Common Bird's-foot Trefoil 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 common bird's-foot trefoil can survive?

Minimum survivable temperature is roughly below about −20 °C. Common Bird's-foot Trefoil is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is common bird's-foot trefoil?

Common Bird's-foot Trefoil is rated USDA 4-9 and RHS H7 — Hardy in the severest European continental winters.

Can common bird's-foot trefoil 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 common bird's-foot trefoil 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.