Zone 9

Zone 9 has the mildest winters covered on this site, with the coldest nights in a typical year reaching only 20 to 30°F. Frost is light and brief, so the real test for perennials is long, hot summers and very little winter chill.

Average coldest winter temperature
20 to 30 °F
In Celsius
-6.7 to -1.1 °C

How Cold Does Zone 9 Get?

Zone 9’s coldest winter night averages 20 to 30°F (-6.7 to -1.1°C) in a typical year, based on 1991 to 2020 weather data. Zone 9a covers 20 to 25°F and zone 9b covers 25 to 30°F. Any perennial whose zone range starts at 9 or lower will survive its winters reliably.

Reliable Perennials for Zone 9

Every plant below is rated hardy in zone 9. Open a profile for planting, care and variety advice.

Close-up of a scarlet bee balm flower head with a ring of narrow, tubular red petals

Bee Balm

Monarda didyma, Monarda fistulosa and hybrids
Zones 4–9Full sunDeer 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
Pink-purple coneflowers with orange-brown centers blooming in a sunny perennial garden bed.

Coneflower

Echinacea spp.
Zones 3–9Full sunDeer resistant
Young coral bells with ruffled copper and amber leaves glowing in the sun, planted in a gravel-mulched bed

Coral Bells

Heuchera spp. and hybrids
Zones 4–9Part shadeDeer 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
Blue-green hosta leaves with pale lavender flower spikes growing in a shaded garden bed.

Hosta

Hosta spp.
Zones 3–9Part shadeDeer favored
Purple lavender flower spikes blooming above silvery-green foliage in a sunny garden bed.

Lavender

Lavandula spp.
Zones 5–9Full sunDeer resistant
Branching silver-white stems of Russian sage lined with small lavender-blue flowers, with a bee feeding on the blooms

Russian Sage

Salvia yangii, formerly Perovskia atriplicifolia
Zones 4–9Full 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 9 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