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Yak Rhododendron

Rhododendron yakushimanum (rho-do-DEN-dron ya-koo-shee-MAH-num)

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

Yaku rhododendron is a woody, evergreen shrub in the Ericaceae (blueberry) family and native to Japan. This compact plant grows slowly into a dense, rounded mound or dome 2 to 3 feet tall and wide, sometimes reaching a height and width of 9 feet. The genus name derives from the Greek words rhodo , which means rose, and dendron , meaning tree. The species name yakushimanu m comes from the island of Yakushima where it is native. Rhododendrons as a whole tend to do better in higher elevations with cooler temperatures. Plant in a location with partial to dappled shade and moist, acidic, well-drained, organically rich soils. It will suffer in hot southern summers and needs protection from afternoon sun though it tolerates sun better than other rhododendrons. This shrub provides year-round interest with its thick, glossy and leathery, curled leaves with velvety brown hairs on the undersurface. New growth is covered in dense white hairs. Attractive dark-pink buds open to light-pink flowers that fade to white in mid-spring. This plant tolerates browsing by rabbits. Use this plant in a container on a patio or in the landscape at the back of a border as an understory, woody shrub in a woodland or natural area. It works well as a low hedge or planted in an Asian or pollinator garden where its flowers will attract bees and other pollinators. 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 but tolerates browsing by rabbits. Early flowering makes it susceptible to spring freezes, especially if planted in sunny locations where leaves and flowers emerge early. 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 offered in partnership with Longwood Gardens. More information on Rhododendron .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 61 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 Rhododendron 'Dr. A. Blok' Rhododendron minus var. chapmanii
Similar, less problematic Abelia x grandiflora Camellia sasanqua Ilex cornuta Rhaphiolepis indica Rhaphiolepis x delacourii

Full plant profile

Growing Conditions
Plant type
Perennial; Poisonous; Shrub
Life cycle
Woody
USDA zones
5b, 6a, 6b, 7a, 7b, 8a, 8b
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
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 9 ft. 0 in. | Width: 2 ft. 0 in. - 3 ft. 0 in.
Maintenance
Low
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Dense; Spreading
Texture
Coarse
Foliage
Broadleaf Evergreen
Leaf color
Brown/Copper; Gray/Silver; Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Lanceolate; Oblanceolate
Leaf margin
Entire
Leaf feel
Glossy; Leathery; Velvety
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
Alternate, simple, glossy gray-green lanceolate to oblanceolate leaves curve downward; abundant brown hairs on underside of leaf; 3 to 3.5 in. long. New growth is covered in velvety white hairs.
Flower color
Pink; White
Flower value
Showy
Flower form
Raceme
Flower shape
Bell
Flower size
1-3 inches
Flower detail
Bright dark rose buds; opening to lighter pink to almost white bell-shaped flowers with 5 petals in late spring to early summer
Bloom time
Spring; Summer
Fruit type
Capsule
Fruit detail
Dry capsule apear in summer and matures in fall and have 5 valves
Wildlife & Ecology
Native status
Non-native
Origin
Japan
Wildlife value
Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli. This plant tolerates damage by rabbits
Attracts
Pollinators; Specialized Bees
Food & Medicine
Harvest time
Fall; Summer
Fruit type
Capsule
Landscape Use
Landscape location
Container; Naturalized Area; Woodland
Landscape theme
Asian Garden; Pollinator Garden
Design feature
Border; Hedge
Garden tags
#showy flowers #deciduous #specialized bees #fall interest #nectar plant #pollinator plant #problem for dogs #problem for horses #problem for cats #bee friendly #evergreen shrub #border planting #slow growing #Asian garden #naturalized area #low maintenance #deer browsing plant #container plant #velvety #hairy leaves #pink flowers #leathery leaves #low hedge #understory planting #understory shrub #flowers late spring #year-round interest #flowers early summer #poisonous #hedge #wildlife friendly #woodland #shrub border #compact
Problems & Resistance
Insect problems
Rhododendron Gall Midge; Rhododendron Borer; Arthropod Pests of Rhododendron; Rhododendron Pest Management Calendar; Rhododendron Lace Bug; Pests of Rhododendron
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Poison severity
Low
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Sap/Juice; 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; Sap/Juice; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.