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Dwarf Purple Rhododendron

Rhododendron impeditum (roh-do-DEN-dron im-ped-EYE-tum)

Family: Ericaceae Non-native Herbaceous (1-3 ft)

Dwarf purple rhododendron is a woody, compact, slow-growing, broadleaf evergreen shrub or groundcover in the Ericaceae (blueberry) family. It is native to China. This rhododendron grows to a height of 1 foot and width of 1 to 2 feet. The genus name derives from the Greek words rhodo , which means rose, and dendron , meaning tree. This plant prefers moist, well-drained, acidic soil in dappled shade and protection from afternoon sun which can scorch the leaves. It does not tolerate dense clay, so if you have clay soil, amend with organic material. The roots may rot if soil does not drain well. Plant the root ball high in the soil to help with drainage issues. Avoid overwatering and over-fertilizing. Dwarf purple rhododendron blooms in the spring with spectacular purple flowers that completely cover the plant. It has fragrant, tiny, leathery, gray-green leaves that provide year-round interest. Plant it in small groups in border fronts, rock, or woodland gardens. Plant it at about 15 inches apart and the plants will grow together to form a dense groundcover. This plant is often chosen for bonsai. It is resistant to damage by deer. 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. 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 rhododendrons 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. 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, 63 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (1-3 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.

Native alternatives Clethra alnifolia Itea virginica
Similar, less problematic Camellia sasanqua Ilex vomitoria 'Dwarf' Rhaphiolepis indica

Full plant profile

Growing Conditions
Plant type
Ground Cover; Poisonous; Shrub
Life cycle
Woody
USDA zones
4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
Light
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
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage
Available space
Less than 12 inches; 12 inches-3 feet
NC region
Coastal; Piedmont
Mature size
Height: 1 ft. 0 in. - 1 ft. 0 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Growth rate
Slow
Maintenance
Low
Canopy layer
4 - Herbaceous (1-3 ft)
Form & Appearance
Habit / form
Dense; Mounding
Foliage
Broadleaf Evergreen
Leaf color
Gray/Silver; Green
Leaf type
Simple
Leaf shape
Ovate
Leaf margin
Entire
Leaf feel
Leathery
Leaf value
Fragrant
Leaf size
< 1 inch long, < 1 inch wide
Hairs present
No
Leaf detail
Fragrant, simple leathery gray-green leaves withe entire margins.
Flower color
Blue; Purple/Lavender
Flower value
Showy
Flower form
Raceme
Flower shape
Funnel
Flower size
1-3 inches
Flower detail
1" blue-purple flowers completely cover the shrub in the mid to late spring
Bloom time
Spring
Fruit color
Brown/Copper
Fruit type
Capsule
Wildlife & Ecology
Native status
Non-native
Origin
China
Wildlife value
Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli.
Attracts
Specialized Bees
Food & Medicine
Harvest time
Fall
Fruit type
Capsule
Landscape Use
Landscape location
Container; Patio; Woodland
Landscape theme
Asian Garden; Rock Garden
Design feature
Border; Mass Planting; Small groups
Garden tags
#showy flowers #dwarf #purple flowers #leathery leaves #tiny leaves #rock garden #border planting #slow growing #border front #fragrant leaves #bonsai #spring flowers #edging #year-round interest #problem for dogs #problem for horses #problem for cats #easy to grow #courtyard garden #flowers late spring #Asian garden #flowers mid-spring #container plant #specialized bees #bee friendly #mass planting #cottage garden #deer resistant #small spaces #gray-green leaves #winter interest #patio #woodland #compact #small groups
Problems & Resistance
Insect problems
Rhododendron Borer; Rhododendron Gall Midge; Arthropod Pests of Rhododendron; Rhododendron Pest Management Calendar; Rhododendron Lace Bug
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Deer
Propagation
Grafting; Layering; Seed
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.