Cold hardiness & minimum temperature

Is Lobed Tickseed (Coreopsis auriculata)cold hardy? Hardiness zone & min temp

Also called Lobed Tickseed, Eared Coreopsis, Mouse-ear Tickseed.

More about lobed tickseed

About Lobed Tickseed

Coreopsis auriculata · also called Lobed Tickseed, Eared Coreopsis · flowering

Lobed Tickseed is a low-growing, semi-evergreen perennial native to open woodlands of the southeastern US, prized for its early-season bright orange-yellow flowers appearing from spring to early summer. It forms spreading mats via stolons and tolerates partial shade better than most coreopsis, making it an excellent ground cover for lightly shaded, dry borders and woodland edges.

Cold limit: USDA 4-9 · RHS H6 (-20–38°C)

What lobed tickseed's hardiness rating actually means

Yes — lobed tickseed is genuinely cold hardy. Rated RHS H6 and USDA 4-9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H6 means: Hardy throughout the UK and northern Europe. 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 about −20 to −15 °C. Lobed Tickseed is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for lobed tickseed as it gets too cold:

It tolerates winter lows to about −20 to −15 °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 lobed tickseed 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 lobed tickseed can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Lobed Tickseed hardiness — frequently asked questions

Is lobed tickseed cold hardy?

Yes — lobed tickseed is genuinely cold hardy. Rated RHS H6 and USDA 4-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Lobed Tickseed 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 lobed tickseed can survive?

Minimum survivable temperature is roughly about −20 to −15 °C. Lobed Tickseed is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is lobed tickseed?

Lobed Tickseed is rated USDA 4-9 and RHS H6 — Hardy throughout the UK and northern Europe.

Can lobed tickseed 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 lobed tickseed below its minimum temperature?

It tolerates winter lows to about −20 to −15 °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.