Notes:
Henning’s Rhododendron & Azalea Pages: rhodyman.net/rhodyn.php
American Rhododendron Society:rhododendron.org
ARS On-line Store: ARSStore.org
Azalea Society of America: azaleas.org
Custom Propagation: vanveennursery.com
Rhododendron Basics by Harold Greer:
Don Hyatt on native azaleas: donaldhyatt.com/natives.html
Hirsutum Archive of Rhododendron & Azaleas Photos:
hirsutum.info/
Tree & Shrub Planting Guide:
rarefindnursery.com/index.php/tree-and-shrub-planting-guide
Mailorder or retail:
Rarefind Nursery in Jackson, NJ: rarefindnursery.com
Greer Gardens in Eugene, OR: greergardens.com
WW Nursery in Indiana, PA: (724) 349-5653
Valley Forge Chapter, ARS, meets at Jenkins Arboretum
valleyforgears.org or
Lehigh Valley Chapter, ARS, meets at Bethlehem VoTech
(Linda Bandala)
Philadelphia Chapter, ARS, meets at Morris Arboretum:
gpchapterars.org or
Rhododendron & Azalea Basics, Steve Henning rhodyman.net
Genus Rhododendron:
Elepidotes: large leaf rhododendrons (Nova Zembla)
Lepidotes: small leaf rhododendrons (PJM)
Evergreen Azaleas (Delaware Valley White)
Deciduous Azaleas (Gibraltar), some very cold hardy
Vireya: tropical from Malaysia, Borneo New Guinea
Some good varieties of rhododendrons:
Boule de Neige, white, 5’, -25F, sun or shade
Catawbiense Album, pinkish-white, 6’. -25F, partial shade
Catawbiense Boursault,-lilac-purple, 6’, -20F, partial shade
English Roseum, lilac-rose, 6’, -25F, partial shade to sun
Lees Dark Purple, purple, 6’, -25F, partial shade
Nova Zembla, red, 5’, -25F, sun or shade
PJM, lavender-pink, 4’, -25F, sun or shade
Roseum Elegans, rosy-lilac, 6’, -25, partial shade
Some good varieties of evergreen azaleas:
Elsie Lee (Shamarello) – 4’, -15F;
Girard’s Fuchsia (Girard) – 3’, -15F;
Girard’s Hot Shot (Girard) – 3’, -15F;
Girard’s Rose (Girard)) – 3’,-10F;
Koromo Shikibu – 5’,-15F; Fragrant
Martha Hitchcock (Glenn Dale)) – 5’, -15F;
Purple Splendor (Gable)) – 3’, -20F;
Stewartsonian (Gable)) – 4’, -20F;
Some good varieties of deciduous azaleas:
Candy Lights (Northern Lights) – 5', -25F, Frag., Mildew. Res.
Gibraltar - (Exbury) – 5’, -25F, Mildew Resistant
Klondyke - (Exbury) – 5', -20F,
Millennium - (Weston) 4', -20F, Frag., Mildew. Res.
Narcissiflora (Ghent) – 6', -15F, Frag., Mildew. Res.
Tri-Lights Lights (Northern Lights) – 5’, -25F, Mildew Res.
Weston's Innocence – (Weston) 3', -25F, Frag., Mildew. Res.
Weston’s Lemon Drop – (Weston) 4’, -35F, Frag., Mildew. Res.
Size: low or dwarf varieties:
Tow Head, greenish-yellow, 1’, -15F, partial shade
R. fastigiatum, lavender-rose, 2’, -15F, partial shade
Purple Gem, lavender to purple, 2’, -25F, partial shade
Dora Amateis, white, 3’, -15F, partial shade to sun
Spreading to Upright
Spreading: Gomer Waterer 5’ -15F, also Yaks.
Upright: PJM 4’, -25F, also deciduous azaleas
Indumentum & Tomentum: natural covering of hairs on leaves.
Ken Janeck – 3’,-25°F, yakushimanum seedling.
Mist Maiden – 3’, -25°F, yakushimanum seedling.
R. degronianum ssp. yakushimanum ‘Exbury' form – 2’, -25°F
R. degronianum ssp. yakushimanum ‘Kiochiro Wada’– 2’, -25°F
Soil: well drained, low pH of 4.5 to 6.
Good drainage: hole drains of water the 2nd time in 1 hour.
For poor drainage or alkaline soil, use a raised bed 8-12” hi.
Chlorotic leaves: yellow with green veins indicate hi pH.
Lower pH with 1 tablespoon of sulfur per square foot.
Planting:Always plant higher in the soil than it was in the pot.
Balled and burlapped (B&B) is best but not very common.
B&B: open up burlap and any wire and spread out in hole.
Containers: make X cut to root ball and spread roots.
Partial Shade is best, but some tolerate full sun or dense shade.
Full Sun:
Rhod: Boule de Neige, English Roseum, Nova Zembla, PJM
Evrgrn Az: hardy Encore Azaleas, Stewarsonian
Dec. Az: Klondyke, Weston’s Innocence
Full Shade (no deciduous azaleas):
Rhod: Boule de Neige, Nova Zembla, PJM, Ramapo
Evrgrn Az: Camilla’s Blush, Lavender Girl, My Mary
Protection: from full sun, deer, drought, winter wind, winter sun
Mulch with pine bark or needles 1.5 to 3 inches deep.
Problems:
Temporary leafcurling is normal in cold and hot.
Curling at other times can be drought or root rot.
Chewed leaf edges is usually weevils which live in ground.
Burned leaf edges is drought, winter damage or fertilizer burn.
Uniform yellow leaves is nitrogen deficiency. Use cotton meal.
Leaf Problems: check backside of leaf for Lace Bug.
White specks on black stems is bark scale & sooty mold.
Stem diebackcan be borers or drought or prolonged winter freeze.
Pruning:
Remove dead branches anytime
Otherwise, pruning is usually not necessary
Prune immediately after blooming to avoid loosing bloom.
Severe pruning: remove up to1/3 each year, not all at once.
Deadheading is removing spent flowers. Not necessary
Native Rhododendrons & Azaleas:
Rhod.: Rs. catawbiense, maximum, minus
Dec. Az.: Rs. canescens, periclymenoides, prinophyllum, viscosum
Fragrant
Azaleas: Evergreen*: Koromo Shikibu; Deciduous: Candy
Lights*, Klondyke, Millennium, Narcissiflora*, Weston’s
Innocence* * indicates mildew resistant.
Rhododendrons:Species.: R. mucronulatum; Hybrids:
Caroline, Janet Blair, Rhona Pink, Tom Everitt, Wheatley
Toxicity: All parts are toxic to some degree.
Companion Trees: Black Gum, Dawn Redwood, Ginkgo,
Japanese Maple, Magnolia, Red Bud, Red Oak, Sweet Gum
Companion Shrubs: Hydrangea, Mountain Laurel, Oregon Grape, Pieris japonica, Viburnum, Witch Hazel
Companion Perennials: Astilbe, Bleeding heart, Fall-blooming crocus, Fall-blooming cyclamen, Fern, Gentian (Gentiana), Heuchera, Hosta, Japanese iris, Ligularia, Primrose, Trillium