Cold hardiness

Future

2050

2100

These values are location-based: this location's current hardiness is the baseline, and the 2050 value is a projected future climate for this same location.

Now

Zone 6b

USDA

Published baseline for this location from 1991-2020.

Source: USDA Plant Hardiness Zone Map 2023 (1991-2020 climatology) via ArcGIS FeatureServer

Well-suited

2050

Zone 7a

Plotwright

Projected zone for this same location in 2050 (2041-2070) using SSP3-7.0 (regional rivalry).

Well-suited

In plain terms: This location is in Zone 6b today. Its hardiness profile is cold winters, and coldest nights are typically around -3°F. By 2050, the projected hardiness zone is Zone 7a based on SSP3-7.0 (regional rivalry). That is a +0.5-zone shift from Zone 6b to Zone 7a by 2050.

✓

Well-suited today and still thriving in 2050.

Heat tolerance

Future

2050

2100

Heat tolerance values are location-based too: heat days today are observed at this site, and the 2050 value projects this same location under a future climate.

Loading AHS heat-zone data for this location...

Where this plant fits

Suitable across 40 ecoregions — 35 climate-resilient through 2070 · 5 suited today. Best matches first.

Appalachian mixed mesophytic forests

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Appalachian-Blue Ridge forests

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Arizona Mountains forests

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Blue Mountains forests

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Canadian Aspen forests and parklands

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Central Pacific Northwest coastal forests

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Central Tallgrass prairie

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Central-Southern Cascades Forests

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Colorado Rockies forests

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Cross-Timbers savanna-woodland

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What it needs

Conditions

Light

Full sun / Part shade

Water

Moderate water

Spacing

18"

Habit

Upright biennial or short-lived perennial forming a basal rosette the first year and a tall flowering spike the second

Care tips

•

Give it cool, moist, rich soil in part shade — it sulks in hot, dry, or soggy sites.

•

Let a few spikes set and drop seed so new rosettes replace the plants that die after blooming.

•

Site it away from where children or pets might nibble it; every part is poisonous.

Lifecycle

Planting

Plant in moist, organically rich, well-drained, acidic soil in part shade (tolerates full sun where summers stay cool); Missouri Botanical Garden PlantFinder rates it for USDA zones 4 to 8. As a biennial or short-lived perennial, set out first-year rosettes in spring or fall for bloom the following year.

Transplanting

Move young rosettes or self-sown seedlings while small and the weather is mild, keeping roots moist; established flowering plants resent disturbance.

Early growth

Keep the soil evenly moist while the rosette establishes; rich, cool, well-drained ground gives the strongest second-year spikes.

Maturity

In its second year the plant reaches 2-5 feet tall and 1-2.5 feet wide, blooming May to June. Missouri Botanical Garden PlantFinder notes that removing flower spikes after bloom can encourage a secondary flush; dense crowns may rot in soggy, poorly drained winter soils.

Propagation

Grows readily from seed and self-sows freely; let a few spikes ripen and scatter seed to keep a colony going. Missouri Botanical Garden PlantFinder lists powdery mildew and leaf spot, plus aphids, mealybugs, slugs, and Japanese beetles, as occasional problems.

Pollination

Self-fertile

Bumblebees are the principal pollinators, working up the one-sided spike of pendulous tubular flowers; the flowers favor cross-pollination but plants set seed readily and self-sow. Missouri Botanical Garden PlantFinder also lists the flowers as attractive to hummingbirds. No separate pollinizer plant is required.

Plants don't grow alone

Pollinates

Bee

Common eastern bumblebee (Bombus impatiens)

Bumble bees are the classic pollinators of foxglove, climbing up into the pendulous tubular flowers for nectar and transferring pollen as they work the spike.

Nectar forage

Bee

American bumblebee (Bombus pensylvanicus)

Long-tongued bumble bees of the genus Bombus are well suited to the deep tubular corollas.

Nectar forage

Bird

Ruby-throated hummingbird (Archilochus colubris)

Missouri Botanical Garden PlantFinder lists the tubular flowers as attractive to hummingbirds.

For people

Toxic — do not consume

Highly poisonous — all parts contain cardiac glycosides, and Missouri Botanical Garden PlantFinder notes the leaves are the source of the heart drug digitalis. Not for culinary use; site away from areas where children or pets might browse it.

Climate notes

•

Missouri Botanical Garden PlantFinder lists Digitalis purpurea for USDA zones 4 to 8, 2-5 ft tall by 1-2.5 ft wide, blooming May to June in full sun to part shade with medium moisture in organically rich, acidic, well-drained soil.

•

Native to western, southern, and central Europe; widely grown as a biennial or short-lived perennial and naturalized in parts of North America. It performs best where summers are cool and resents hot, humid conditions.

•

Missouri Botanical Garden PlantFinder records the flowers as attractive to hummingbirds and the plant as tolerant of rabbits and deer, while cautioning that crowns rot in poorly drained winter soils and that powdery mildew, leaf spot, aphids, mealybugs, slugs, and Japanese beetles can occur.

In the designer

Growth over time

24-60" tall · 12-30" spread

Second year: sends up the tall 2-5 ft flowering spike in late spring, sets seed, then usually declines; self-sown seedlings carry the planting forward.

Design roles: Border · Pollinator · Focal point

Common foxglove

At a glance

Related products

Why it matters

Cold hardiness

Heat tolerance

Where this plant fits

What it needs

Lifecycle

Pollination

Plants don't grow alone

For people

Climate notes

In the designer

Sources & citations