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

Won't grow here

2050

Zone 7a

Plotwright

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

Won't grow here

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.

✕

Out of range today and still out of range 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 17 ecoregions — 11 climate-resilient through 2070 · 6 newly possible by 2070. Best matches first.

Atlantic coastal pine barrens

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California coastal sage and chaparral

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Central Pacific Northwest coastal forests

Eastern Australian temperate forests

New Zealand North Island temperate forests

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Northern Pacific Alaskan coastal forests

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What it needs

Conditions

Light

Full sun / Part shade

Water

Consistent moisture

Spacing

14"

Habit

Mounding tender perennial grown as a warm-season annual

Care tips

•

Choose New Guinea impatiens specifically where impatiens downy mildew has ruined common impatiens — it is resistant to the disease and keeps blooming.

•

Give it part shade to morning sun with consistently moist, rich soil; it takes more sun than common impatiens but still scorches and wilts in dry, hot full sun.

•

Set out nursery starts only after the last frost and warm soil, and pinch young plants to keep them branching and compact.

Lifecycle

Planting

Grow in moist, organically rich, well-drained soil in part shade to full sun — it takes more sun than common impatiens but still wants afternoon shade and steady moisture in hot climates. Buy nursery starts in spring (it is rarely grown from seed) and set them out only after the last frost once soil has warmed. Space plants about 14 inches apart.

Transplanting

Move hardened-off container starts out after frost danger passes, ideally on an overcast day or late afternoon, and water in well; keep moisture even while roots establish.

Early growth

Pinch young plants to keep them branching and compact. Keep the soil consistently moist — the succulent stems wilt quickly when dry, and even moisture produces the best flowering.

Maturity

Forms an 18-36 inch mound 6-24 inches tall, blooming continuously through the warm season. In USDA Zones 10-12 it persists as a tender perennial; elsewhere it is killed by frost and replanted each year.

Propagation

Almost always propagated from softwood stem cuttings (it sets little viable seed and most plants are vegetative cultivars); root cuttings in water or moist media, and overwinter stock plants indoors in cold climates.

Pollination

Self-fertile

Grown as a vegetatively propagated bedding annual that sets little viable seed; the spurred flowers hold nectar and are visited by long-tongued nectar feeders, so it functions as an ornamental nectar source rather than a keystone habitat plant. No pollination partner is required for its garden use.

Plants don't grow alone

Nectar forage

Bird

Ruby-throated hummingbird (Archilochus colubris)

The slender-spurred, nectar-bearing flowers plausibly attract long-billed, long-tongued nectar feeders such as the ruby-throated hummingbird, as the related common impatiens does; graded plausible because this is a non-native frost-tender bedding annual rather than a documented keystone nectar plant.

For people

Not eaten by humans

Grown purely as an ornamental part-shade-to-sun bedding, container, and hanging-basket annual; it is not a food crop and has no notable edible use.

Climate notes

•

NC State Extension lists Impatiens hawkeri for USDA hardiness zones 10a-12b; it is native to New Guinea and not native to the United States.

•

It is a tender perennial, hardy only in Zones 10-12, so across most of North America it is grown as a frost-killed warm-season bedding annual — say so before treating it as permanent.

•

Its defining advantage is resistance to impatiens downy mildew (Plasmopara obducens), the pathogen that devastated Impatiens walleriana plantings; this is the honest reason to choose it where that disease is established.

•

It tolerates more sun than common impatiens and real summer heat, but only with consistent moisture — in dry extreme heat or full afternoon sun without water it scorches and wilts, so it is not a low-water annual.

In the designer

Growth over time

3-12" tall · 7-14" spread

Set out transplants only after the last frost and once soil has warmed; pinch to encourage branching.

Design roles: Filler · Border · Container

Seasonal interest

Spring

Summer

Fall

Winter

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

New Guinea impatiens

At a glance

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

Seasonal interest

Sources & citations