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 45 ecoregions — 45 climate-resilient through 2070. 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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Atlantic coastal pine barrens

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Blue Mountains forests

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California coastal sage and chaparral

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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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What it needs

Conditions

Light

Full sun / Part shade

Water

Moderate water

Spacing

12"

Habit

Upright bushy cool-season annual herb

Care tips

•

Treat it as a cool-season annual: it blooms longest in cool weather and may stall in midsummer heat.

•

Deadhead spent flowers, and cut plants back hard if they languish in hot weather to push a fresh flush of fall bloom.

•

Pinch young plants to keep them compact and bushy; give some afternoon shade in hot-summer climates.

Lifecycle

Planting

An annual easily grown in average, moderately fertile, well-drained soil in full sun. Start seed indoors 6-8 weeks before the last frost date or sow directly in the garden just before the last frost date; set out seedlings or purchased starts after the last frost date. In hot-summer climates such as St. Louis, plants appreciate some afternoon shade but become leggy in too much shade (Missouri Botanical Garden).

Transplanting

Set hardened-off seedlings or purchased starter plants out after the last frost date; avoid burying the crown.

Early growth

Keep soil at medium moisture while plants establish. Pinch young plants back to encourage compact bushy growth, and watch for slugs, snails, aphids, and whiteflies, particularly on young plants (NC State Extension).

Maturity

Mature plants reach 1-2 feet tall and wide and bloom over a long summer-to-fall window in cool climates. Deadhead spent flowers to promote additional bloom. If plants begin to languish in prolonged hot weather, cut them back to promote fall flowering; in hot St. Louis summers they often will not last the whole growing season (Missouri Botanical Garden).

Propagation

Grown from seed; sow indoors 6-8 weeks before last frost or direct-sow just before the last frost date. Frequently reseeds in the garden.

Pollination

Self-fertile

An open-pollinated insect-attracting composite — Missouri Botanical Garden and NC State Extension both document Calendula officinalis as attracting butterflies and pollinators. It is grown easily from seed and frequently reseeds in the garden.

Plants don't grow alone

Nectar forage

Fly

Hover flies (flower flies) (Syrphidae)

Nectar forage

Butterfly

Black swallowtail (Papilio polyxenes)

Missouri Botanical Garden and NC State Extension both list Calendula officinalis as attracting butterflies; the showy open composite flowerheads offer accessible nectar to butterflies such as swallowtails, though the sources name only the butterfly category rather than this species.

Nectar forage

Bee

European honeybee (Apis mellifera)

NC State Extension lists Calendula as attracting pollinators generally; its open, abundant flowerheads are readily worked by honey bees and other generalist bees, though the sources do not name a specific bee species.

Pollen forage

Bee

Leafcutter bees (Megachile spp.)

Shelter / habitat

Beetle

Lady beetles (Coccinellidae)

For people

Edible

The somewhat bitter flowers and lance-shaped leaves are edible and may be added fresh or dried to soups, salads, or rice dishes for color and flavor (Missouri Botanical Garden). NC State Extension notes the flower petals give color to soups, custards, and rice and are also used in cookies and vinegars, and the flowers yield a yellow dye. NC State also rates Calendula non-toxic to dogs and cats.

Edible parts

flowers, petals, leaves

Pet toxicity

NC State Extension lists Calendula officinalis as non-toxic for dogs and non-toxic for cats.

Native range

AHS heat range

1-9

Climate notes

•

Missouri Botanical Garden PlantFinder lists Calendula officinalis as an annual for USDA zones 2-11, full sun to part shade, medium water, blooming bright yellow to deep orange.

•

NC State Extension lists it across USDA zones 2a-11b in full sun to partial shade, with good-drainage-to-moist soils, and rates it resistant to black walnut, deer, heat, humidity, and rabbits.

•

A cool-season annual: it blooms longest in cool climates and tends to languish in prolonged hot summer weather, where Missouri Botanical Garden recommends afternoon shade and a midseason cutback to recover fall bloom. Grown as an annual everywhere — the zone range reflects annual culture, not winter hardiness.

In the designer

Growth over time

5-11" tall · 5-10" spread

Seedling-to-young-plant stage; pinch back to encourage compact bushy growth.

Design roles: Border · Edible · Pollinator · Container

Seasonal interest

Spring

Summer

Fall

Winter

Filled = the plant has seasonal interest · ▾ now = your current season

Calendula (pot marigold)

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

Native range

Climate notes

In the designer

Seasonal interest

Sources & citations