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Southern Indian Azalea

Rhododendron indicum (roh-do-DEN-dron IN-dih-kum)

Family: Ericaceae Non-native Shrub (3-15 ft)

Southern Indian azalea is a small, semi-evergreen shrub in the Ericaceae (blueberry) family that is native to Japan. This compact azalea has a mature size of about 2 to 3 feet in both height and width. While it has a dense canopy it can spread. The genus name, Rhododendron, derives from the Greek words rhodo , which means rose, and dendron , meaning tree. This plant prefers partial shade and acicic well drained soil that is moist and high in organic material. It is intolerant of heavy and wet soils, drought, and excessive fertilization. It has a slow growth rate and requires a high level of maintenance including removing spent flower clusters immediately after flowering. Southern Indian azalea has showy, hot pink to burgundy flowers that bloom in mid to late spring and occasionally again in the fall. It works well in the landscape as an understory shrub mass planted or in small groups in woodland or naturalized areas, or as specimens in pollinator gardens where the flowers will attract bees. It can also be used as a low hedge or in a winter garden where its leaves turn attractive shades of red. Quick ID Hints: Small shrub, sympodial growth, with crowded evergreen leaves in tiers Twigs & leaves covered with reddish-brown hairs Flowers axillary, single in spring with funnel-form corolla Calyx 5-lobed, elongated & pointed 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. 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 listed in the left-hand sidebar. 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 developed in partnership with Longwood Gardens. More information on Rhododendron .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 62 attributes.

How it fits the guild

Guild layer 3 - Shrub (3-15 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.

Fills a similar niche Rhododendron 'Dr. A. Blok' Rhododendron 'Girard' s Crimson' Rhododendron indicum 'Coral Bells'

Full plant profile

Growing Conditions
Plant type
Poisonous; Shrub
Life cycle
Woody
USDA zones
7a, 7b, 8a, 8b
Light
Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter; Loam (Silt)
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist
Available space
12 inches-3 feet
NC region
Coastal; Piedmont
Mature size
Height: 2 ft. 0 in. - 3 ft. 0 in. | Width: 2 ft. 0 in. - 3 ft. 0 in.
Growth rate
Slow
Maintenance
High
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Dense; Spreading
Foliage
Broadleaf Evergreen
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Lanceolate; Oblanceolate
Leaf margin
Crenate; Serrate
Hairs present
Yes
Leaf detail
Leaves are alternate, simple, crowded, and consist of evergreen (winter) leaves and deciduous (seasonal) leaves. Blades are narrowly lanceolate to oblanceolate, crenate-serrulate (slightly toothed), with scattered reddish-brown hairs on veins below. Petiole is pubescent with stiff reddish-brown hairs. Leaves turn reddish in the winter.
Fall color
Red/Burgundy
Flower color
Pink; Red/Burgundy
Flower value
Showy
Flower form
Raceme
Flower shape
Funnel
Flower detail
Flowers are axillary, single to rarely double, non hose-in-hose, bright red to scarlet to pinkish-red or white. There are 5 calyx lobes that are elongated, narrow, and acutely pointed. Corolla is funnel-form, 1-2" in size, have 5 lobes with the upper central lobe and sometimes the lateral pair bearing conspicuous maculation. They bloom in mid to late spring and sometimes again in the fall.
Bloom time
Fall; Spring
Fruit type
Capsule
Fruit detail
Fruits are a dehiscent 5-valved capsule.
Stem detail
Twigs are pubescent with stiff reddish-brown trichomes and has sympodial growth.
Wildlife & Ecology
Native status
Non-native
Origin
Japan
Wildlife value
Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli. Deer browse this plant.
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Woodland
Landscape theme
Shade Garden; Winter Garden
Design feature
Border; Foundation Planting; Hedge; Mass Planting; Small groups
Garden tags
#rabbit resistant #evergreen shrub #showy flowers #spring flowers #pink flowers #evergreen #winter interest #fantz #problem for cats #problem for dogs #problem for horses #shade garden #disease problems #winter color red #flowers late spring #foundation planting #slow growing #specimen #low hedge #flowers early fall #flowers mid-spring #wet soils intolerant #mass planting #high maintenance #poisonous #hot pink flowers #hedge #woodland #shrub border #small groups
Problems & Resistance
Insect problems
Arthropod Pests of Azalea; Azalea Pest Management Calendar; Pests of Azalea; Azalea Lace Bug; Azalea Plant Bug; Azalea Leafminer; Azalea Caterpillar; Azalea Stem Borer
Disease problems
Southern Blight of Herbaceous Ornamentals
Problems
Frequent Disease Problems; Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Rabbits
Poison severity
Low
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Sap/Juice
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; Sap/Juice

Planted at Hunnicutt

Nobody’s planted this one yet.