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PJM Rhododendron

Rhododendron (roh-do-DEN-dron)

Family: Ericaceae Unknown Shrub (3-15 ft)

PJM rhododendrons are a group of hybrid, broadleaf evergreen shrubs in the Ericaceae (blueberry) family that were developed by Peter J. Mezitt and his son in the 1930s to be exceptionally winter hardy. Growing 3 to 6 feet tall and wide, these rhododendrons prefer partial shade and protection from strong winds. They grow well in moist, acidic soils but do not like wet feet. If you have clay soil, amend it with organic material and plant the root ball high in the soil to help with drainage issues. Avoid overwatering and over-fertilizing. Pruning, if desired, may be done after flowering. This plant is resistant to browsing by rabbits. As with all members of the genus, PJM rhododendrons are perfect as mass plantings in woodland or natural areas and specimens in pollinator gardens. Their green foliage acquires purple tones in winter, making them a wonderful addition to a winter garden. They also make a great informal hedge plant. 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. Full sun can scorch the leaves, and the roots rot if soil does not drain well. 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 developed in partnership with Longwood Gardens. More information on Rhododendron .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 59 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.

Often confused with Edgeworthia chrysantha
Similar, less problematic Abelia x grandiflora Camellia sasanqua Ilex cornuta Rhaphiolepis indica Rhaphiolepis x delacourii

Full plant profile

Growing Conditions
Plant type
Poisonous; Shrub
Life cycle
Woody
USDA zones
4a, 4b, 5a, 5b, 6a, 6b, 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
Available space
3 feet-6 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 3 ft. 0 in. - 6 ft. 0 in. | Width: 3 ft. 0 in. - 7 ft. 0 in.
Growth rate
Medium
Maintenance
Medium
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Rounded
Texture
Coarse
Foliage
Broadleaf Evergreen
Leaf color
Green
Leaf arrangement
Alternate
Leaf shape
Elliptical
Leaf margin
Entire
Leaf feel
Leathery
Leaf size
1-3 inches long
Hairs present
No
Leaf detail
Elliptic, hairless, leathery, dark green leaves (to 2.5” long); foliage acquires purple tones in winter.
Fall color
Purple/Lavender
Flower color
Pink; Purple/Lavender
Flower value
Showy
Flower form
Raceme
Flower shape
Funnel
Flower detail
Showy clusters of lavender, pink or rose flowers
Bloom time
Spring
Fruit type
Capsule
Wildlife & Ecology
Native status
Unknown
Wildlife value
Tolerates damage by rabbits. Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli.
Attracts
Specialized Bees
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Naturalized Area; Woodland
Landscape theme
Pollinator Garden; Winter Garden
Design feature
Hedge; Mass Planting; Specimen
Garden tags
#hardy #dappled shade #specialized bees #winter interest #native bees #evergreen #rabbit resistant #problem for dogs #problem for horses #problem for cats #bee friendly #shade garden #flowers mid-spring #winter hardy #wet soils intolerant #winter garden #mass planting #purple leaves #leathery leaves #poisonous #understory shrub #buncombe county sun and shade garden #hedge #wildlife friendly
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
Resistant to
Rabbits
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.