Zone 3

Zone 3 is one of the coldest zones where perennial gardens thrive, with winter nights that fall to -30°F or below in a typical year. The perennials that succeed here are tough, fully dormant plants that come back reliably each spring.

Average coldest winter temperature
-40 to -30 °F
In Celsius
-40 to -34.4 °C

How Cold Does Zone 3 Get?

Zone 3’s coldest winter night averages -40 to -30°F (-40 to -34.4°C) in a typical year, based on 1991 to 2020 weather data. Zone 3a covers -40 to -35°F and zone 3b covers -35 to -30°F. Any perennial whose zone range starts at 3 or lower will survive its winters reliably.

Reliable Perennials for Zone 3

Every plant below is rated hardy in zone 3. Open a profile for planting, care and variety advice.

Astilbe

Astilbe spp.
Zones 3–8Part shadeDeer resistant
Golden black-eyed Susan flowers with dark brown centers blooming in a perennial garden bed.

Black-Eyed Susan

Rudbeckia spp.
Zones 3–9Full sunDeer resistant
A wide, soft mound of 'Walker's Low' catmint covered in lavender-blue flower spikes in a sunny garden bed

Catmint

Nepeta × faassenii, Nepeta racemosa and hybrids
Zones 3–8Full sunDeer resistant
Pink-purple coneflowers with orange-brown centers blooming in a sunny perennial garden bed.

Coneflower

Echinacea spp.
Zones 3–9Full sunDeer resistant
Long bands of magenta and white creeping phlox in full bloom covering the sloped bank of a narrow river in spring

Creeping Phlox

Phlox subulata
Zones 3–9Full sunSometimes browsed
A cluster of garden phlox with pink-and-white striped flowers surrounded by violet-purple phlox blooms

Garden Phlox

Phlox paniculata
Zones 3–8Full sunSometimes browsed
Blue-green hosta leaves with pale lavender flower spikes growing in a shaded garden bed.

Hosta

Hosta spp.
Zones 3–9Part shadeDeer favored
Pink peony blooms and buds growing on a leafy clump in a perennial garden bed.

Peony

Paeonia spp.
Zones 3–8Full sunDeer resistant
A dense mat of 'Angelina' sedum with bright chartreuse, needle-like leaves on trailing stems

Sedum

Sedum and Hylotelephium spp.
Zones 3–9Full sunDeer resistant

USDA Hardiness Zones at a Glance

Each zone is 10°F warmer than the one before it. Use the table to compare zone 3 with its neighbors.

Average Annual Extreme Minimum Temperature by Zone
ZoneFahrenheitCelsiusPlants
Zone 3-40 to -30 °F-40 to -34.4 °C9
Zone 4-30 to -20 °F-34.4 to -28.9 °C13
Zone 5-20 to -10 °F-28.9 to -23.3 °C14
Zone 6-10 to 0 °F-23.3 to -17.8 °C14
Zone 70 to 10 °F-17.8 to -12.2 °C14
Zone 810 to 20 °F-12.2 to -6.7 °C14
Zone 920 to 30 °F-6.7 to -1.1 °C9