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PJM Rhododendron (group)

Common Name: PJM Rhododendron (group)
Scientific Name Genus: Rhododendron
Family Name: Ericaceae

Cultural Comments

PJM rhododendron are best grown in an acidic, moist, well-drained soil in part to full shade. Dappled shade is preferred; full sun may result in leaf scorch. Should be sited in areas protected from strong winter winds. PJM should not be planted in wet areas as root rot can be an issue, but also should not be allowed to dry out. Mulching helps to maintain soil moisture. Hardy to zone 4; good winter hardiness.

Native Habitat

The PJM group is a group of Rhododendron hybrids resulting from crosses between R. Carolinianum and R. dauricum var. sempervirens. The original breeding for this group of hybrids was done at Weston Nurseries by Edmund and Peter J. Mezitt.

Growth Habit

Compact, rounded growing 3-6' tall and wide.

Leaves

Dark green, hairless leaves are elliptical in shape growing 1-2.5" long.
Evergreen, stiff, leathery leaves with a rusty-orange, scaly underside.
Has a purple-green color in winter.
PJM Rhododendron winter leaf color

Flowers

Bright lavender pink flowers in clusters of 4-9.
PJM Rhododendron flowers

Bloom Time

Spring; April

Common Problems

Similar to other Rhododendrons PJM hybrids are susceptible to various issues including canker, crown rot, root rot, leaf spot, rust, powdering mildew, aphids, borers, lacebugs, mealybugs, mites, scale, thrips, and whitefly.
Properly sited plants have few problems.

Varieties or Cultivars

PJM Compact - similar to PJM but with larger flowers. Upright and spreading.
'PJM Compact Briggs' - lavender pink, smaller habit
'PJM Lavender' - lavender pink flowers; early flowering; winter leaves reddish-brown; semi-dwarf
'PJM White Form' - white flowered form

Landscape Uses

Good for shrub borders, woodland and shade gardens, or for foundation plantings. Can be used a s specimen or in groups. Effective in mass.
PJM Rhododendron

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