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Hoary Azalea

Rhododendron canescens (rho-doh-DEN-dron kan-ESS-senz)

Family: Ericaceae Native Understory (15-40 ft)

Southern pinxter azalea is a large woody, deciduous shrub in the Ericaceae (blueberry) family. This native shrub is found growing in moist woods, swamp margins, and along streams from North Carolina to Florida and west to Tennessee, Arkansas, and Texas. The genus name derives from the Greek words rhodo , which means rose, and dendron , meaning tree. The specific epithet canescens means gray or off-white hairs refering to the hairs found on the undersides of the leaves. Plant this azalea in moist, well-drained, acidic soil that is high in organic matter. It will not tolerate dense clay or poorly drained soil so those soils will need to be amended before planting. Ideal light requirements are dappled sunlight to partial shade. It will grow in full sun if protected from afternoon sun, which can scorch the leaves. This plant propagates slowly by root suckers and its shallow roots appreciate a yearly application of mulch. Rabbit browsing is tolerated well. It typically grows to 6 to 8 feet tall and less frequently may grow to 15 feet tall. It will be 6 to 10 feet wide at maturity. The leaves are thick and velvety and appear after the showy light pink flowers with very prominent stamens in the spring. Flowers should be deadheaded after bloom. The bark is an interesting gray to reddish/brown and finely shredded. In the fall, leaves turn a burgundy red. Prune rhododendrons and azaleas after they bloom to preserve the current season's bloom, and allow time for the plant to produce flower buds for next year's bloom. Rhododendrons and azaleas set next year's flower buds by mid to late summer. Southern pinxter azalea is ideal for a mass planting in woodland or naturalized area. Add it to a pollinator garden where its showy, fragrant flowers will attract butterflies, bees, and hummingbirds. Or use it in a shrub border or as an attractive hedge to line a walkway. Insects, Diseases, and Other Plant Problems: Insect problems include aphids, borers, lace bugs, leafhoppers, mealybugs, mites, nematodes, scale, thrips, and whitefly. Diseases include canker, crown rot, root rot, leaf spot, rust, and powdery mildew. This plant is frequently damaged by deer. While these shrubs remain very popular for landscape use, many cultivars are susceptible to Phytophthora root rot—this leads to leaf loss, reduced vigor, branch dieback, and wilting. Implement good cultural practices first, such as improving drainage with organic matter or berms and avoiding overwatering or overfertilization. However, if you have a site with a history of this disease, consider planting one of the root rot-resistant alternative species. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common diseases of rhododendron. For suitable alternatives, see this video created by Charlotte Glen as part of the Plants, Pests, and Pathogens series. VIDEO Created by Elizabeth Meyer for " Trees, Shrubs and Conifers " a plant identification course offered in partnership with Longwood Gardens. More information on Rhododendron .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 67 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Full plant profile

Growing Conditions
Plant type
Native Plant; Perennial; Poisonous; Shrub
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Dappled Sunlight (Shade through upper canopy all day) | Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist | Occasionally Wet
Available space
6-feet-12 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 6 ft. 0 in. - 15 ft. 0 in. | Width: 6 ft. 0 in. - 10 ft. 0 in.
Maintenance
Medium
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Multi-trunked
Texture
Medium
Foliage
Deciduous
Leaf color
Green; Red/Burgundy
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Elliptical; Obovate
Leaf margin
Serrate
Leaf feel
Leathery; Velvety
Leaf size
3-6 inches long, < 1 inch wide
Hairs present
Yes
Leaf detail
Obovate to elliptic, dull velvety and thick dark green leaves (to 3” long and 3/4" wide) which are gray-pubescent (canescent) beneath. The leaves, which are alternate and simple with a finely toothed margin, have rusty red fall color.
Fall color
Red/Burgundy
Flower color
Pink; White
Flower value
Fragrant; Showy
Flower form
Raceme
Flower shape
Funnel
Flower size
1-3 inches
Flower detail
Clusters (5-9 flowers per cluster) of fragrant, funnel-shaped, pink (infrequently white) flowers (1-2” long) in early spring as the foliage begins to emerge. Pistil and stamens of each flower protrude well beyond the corolla in an upward arch. It has a delicate sweet fragrance and sticky feel. Blooms from March to May.
Bloom time
Spring
Fruit type
Capsule
Fruit size
< 1 inch long
Fruit detail
Woody, elongated capsules 1/2" long. Displays from September to October.
Bark color
Light Brown; Light Gray; Red/Burgundy
Wildlife & Ecology
Native status
Native
Distribution
North Carolina to Florida west to Tennessee, Arkansas and Texas
Wildlife value
Hummingbirds and swallowtail butterflies are attracted to the blooms.
Attracts
Bees; Butterflies; Hummingbirds; Pollinators; Small Mammals; Specialized Bees
Food & Medicine
Harvest time
Fall
Fruit type
Capsule
Landscape Use
Landscape location
Naturalized Area; Walkways; Woodland
Landscape theme
Butterfly Garden; Native Garden; Pollinator Garden; Shade Garden
Design feature
Border; Foundation Planting; Hedge; Mass Planting; Specimen
Garden tags
#specialized bees #deciduous #hummingbird friendly #native bees #drought tolerant #nectar plant #poisonous #multitrunked #pollinator plant #NC native #native shrub #butterfly friendly #Piedmont Mountains FACW #food source herbage #larval host plant #food source nectar #food source pollen #mammals #Coastal FACW #food source fall #problem for cats #problem for dogs #problem for horses #Audubon #bee friendly #rabbit resistant #leathery leaves #flowers late spring #flowers early spring #NC Native Pollinator Plant #flowers mid-spring #velvety #fall interest #fragrant flowers #fall color red #deciduous shrub #wet soils intolerant #mass planting #large shrub #hedge #wildlife friendly #shrub border #walkway #bat friendly #moth friendly
Problems & Resistance
Insect problems
Azalea Lace Bug; Azalea Plant Bug; Azalea Caterpillar; Azalea Stem Borer; Azalea Leafminer; Azalea Bark Scale; Azalea Whitefly; Azalea Pest Management Calendar; Arthropod Pests of Azalea; Pests of Azalea
Disease problems
Southern Blight of Herbaceous Ornamentals
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Rabbits
Propagation
Root Cutting
Poison severity
Low
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Seeds; Stems
Poison symptoms
While the plants are known to contain toxins, ingestion of moderate amounts of azalea (nectar or leaves) poses little toxic hazard.
Toxic principle
Grayanotoxins
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Bark; Flowers; Fruits; Leaves; Roots; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.