Rhododendron
Description
General: Rhododendron is a genus of over 1,000 species of trees and shrubs. Although we don’t have 1,000 we do have numerous varieties ranging from small to large, that are cold hardy and when in bloom, provide beautiful color. Through testing and trials, we have found at least 20 different beautiful Rhododendron that have done well in our climate. The information below is based on our experience.
Leaves: Dark green, eliptical in shape, (1-8″ long), can be glossy depending on the species. Certain species or cultivar will have heavy pubescence ranging from peach to white coloring on the underside of the leaf.
Flowers: Numerous flowers form in clusters on the entire shrub in a variety of colors (whites, pinks, oranges, yellows, reds, purples) depending on the species or cultivar.
Attributes: An evergreen shrub with a spectacular flower display, brings beauty to a landscape at a time when there isn’t much color going on. As we come out of winter, a Rhododendron in bloom helps us look forward to spring and forget about the cold. Use along wooded borders, along foundations, as hedges or solitary plants. We use different types of Rhodies together that have staggered bloom times to lengthen the amount of color in a certain area. Rhododendron are a great choice to add some early color to your landscape.
Culture
Hardiness: Zones 4- 8 for the Rhododenrons we have here at Great Hill.
Growing Conditions: Prefers a moist, well-drained acidic soil in a partially sunny to partially shady location. Best to protect from heavy drying winds.
Maintenance: The amount of pruning needed will depend on the location and purpose of the plant. Rhodies can be kept smaller with frequent pruning, large trees can also be reduced heavily to rejuvinate the shrub when they have become too large for their space. Fungal issues can be a problem for foliage causing leaves to fall off prematurely. Lacebug is probably the most common Rhodie pest and is usually seen when planted in full sun. Some scales and ahpids are common as well as Black Vine Weevil which will chew on leaves making them unsightly.
Transplanting: They can be trasplanted anytime, but if they are moved while putting on new growth, the new growth may die back. Maintain adaquate moisture during the plants establishment.
Propagation: Cutting
Our Experience
Experience at Great Hill: While we have numerous Rhododendrons that have done well, we have seen some types that have struggled. One of the biggest issues we have is exposure. Full, hot sun can be drying and stressful to the plant. While they can tolerate a good amour of sun, they do benefit from some protection. Also, a Rhododendron planted in full sun will be susceptible to lace-bug. When planted in an area that is exposed to strong winter winds, die back can be expected as the plant gets desiccated.
Historical Winter Data
Winter 2016-17: Some winter injury on recently transplanted shrubs, probably due to stress going into the winter, or exposure to the elements of the winter.
Winter 2017-18: Some broken branches due to heavy snow loads in March.
Rhododendron Bloom Data 2023
Rhododendron Bloom Data 2023
| Plant Name | Bud Break | Full Bloom | Bloom Drop |
|---|---|---|---|
| Anah Krusche | NO BLOOM | ||
| Goldflimmer | NO BLOOM | ||
| Holden | NO BLOOM | ||
| Wilson | NO BLOOM | ||
| Janet Blair | NO BLOOM | ||
| PJM Elite | April 15 | May 1 | May 11 |
| Roseum | May 18 | May 24 | June 11 |
| Olga Mezitt | April 22 | May 6 | May 17 |
| Vinecrest | NO BLOOM | ||
| Summer Rose | NO BLOOM | ||
| Catawbiense 'Boursault' | NO BLOOM | ||
| Pauline Bralit | NO BLOOM | ||
| Maximum 'Independence' | NO BLOOM | ||
| Lavender Queen | NO BLOOM | ||
| April Snow | April 16 | April 23 | May 10 |
| April Dawn | April 15 | April 28 | May 9 |
| catawbiense 'Album' | May 23 | May 31 | June 18 |
| yaku 'Princess' | May 12 | May 18 | May 25 |
| yaku 'Prince' | May 12 | May 20 | May 25 |
| Cunningham's White | NO BLOOM | ||
| Westons Pink Diamond | NO BLOOM | ||
| Boule De Neige | NO BLOOM | ||
| Delaware Valley White | NO BLOOM | ||
| Purple Gem | May 3 | May 10 | May 24 |
| x PJM compacta | April 14 | April 22 | April 29 |
| Molly Fordham | NO BLOOM | ||
| Renee Michelle | NO BLOOM | ||
| Hot Shot | NO BLOOM | ||
| Komo Kulshan | May 10 | May 18 | June 3 |
| Blaauws Pink | NO BLOOM | ||
| PJM Regal | April 14 | April 25 | May 11 |
| PJM Victor | April 14 | April 25 | May 6 |
| PJM Red Quest | NO BLOOM | ||
| Amoena | May 8 | May 18 | May 25 |
| Karen | NO BLOOM | ||
| Hebert | May 8 | May 16 | June 2 |
| Springtime | NO BLOOM | ||
| catawbiense 'Grandiflorum' | May 23 | May 27 | June 13 |
| Poukhanense | NO BLOOM |
Rhododendron Bloom Data 2022
Rhododendron Bloom Data 2022
| Plant Name | Bud Break | Full Bloom | Bloom Drop |
|---|---|---|---|
| Anah Krusche | May 21 | June 1 | June 12 |
| Goldflimmer | May 28 | June 6 | June 26 |
| Holden | May 12 | May 21 | June 1 |
| Wilson | June 3 | June 9 | June 22 |
| Janet Blair | May 19 | May 29 | June 9 |
| PJM Elite | April 22 | May 3 | May 12 |
| Roseum | May 16 | May 27 | June 5 |
| Olga Mezitt | April 25 | May 12 | May 20 |
| Vinecrest | May 1 | May 16 | June 3 |
| Summer Rose | June 18 | June 27 | July 12 |
| Catawbiense 'Boursault' | May 21 | June 1 | June 15 |
| Pauline Bralit | May 11 | May 19 | May 31 |
| Maximum 'Independence' | June 13 | June 21 | July 6 |
| Lavender Queen | May 9 | May 18 | May 30 |
| April Snow | April 10 | April 26 | May 14 |
| April Dawn | April 12 | May 1 | May 14 |
| catawbiense 'Album' | May 15 | May 25 | June 3 |
| yaku 'Princess' | May 16 | May 21 | June 5 |
| yaku 'Prince' | May 16 | May 21 | June 3 |
| Cunningham's White | April 25 | May 9 | May 18 |
| Westons Pink Diamond | April 7 | April 22 | May 8 |
| Boule De Neige | May 13 | May 21 | June 1 |
| Delaware Valley White | May 16 | May 25 | June 1 |
| Purple Gem | April 25 | May 10 | May 25 |
| x PJM compacta | April 18 | May 3 | May 13 |
| Molly Fordham | April 22 | May 1 | May 15 |
| Renee Michelle | May 16 | May 25 | June 3 |
| Fire Dancer | April 28 | May 20 | June 4 |
| Hot Shot | May 8 | May 18 | June 7 |
| Komo Kulshan | May 12 | May 25 | June 5 |
| Blaauws Pink | May 16 | May 30 | June 7 |
| PJM Regal | April 14 | April 28 | May 14 |
| PJM Victor | April 12 | April 24 | May 12 |
| PJM Red Quest | April 10 | April 24 | May 12 |
| Amoena | May 9 | May 18 | June 3 |
| Karen | April 26 | May 18 | June 3 |
| Hebert | May 8 | May 20 | June 3 |
| Springtime | April 23 | May 12 | May 21 |
| catawbiense 'Grandiflorum' | May 25 | June 1 | June 14 |
| Poukhanense | May 9 | May 18 | May 31 |
Rhododendron Bloom Data 2021
Rhododendron Bloom Data 2021
| Plant Name | Bud Break | Full Bloom | Bloom Drop |
|---|---|---|---|
| Anah Krusche | May 20 | June 3 | June 15 |
| Goldflimmer | May 21 | June 10 | June 16 |
| Holden | May 15 | May 24 | June 10 |
| Wilson | May 30 | June 11 | June 25 |
| Janet Blair | May 21 | June 3 | June 11 |
| PJM Elite | April 10 | April 26 | May 10 |
| Roseum | May 24 | June 8 | June20 |
| Olga Mezitt | April 24 | May 5 | May 21 |
| Vinecrest | April 29 | May 14 | April 29 |
| Summer Rose | June 12 | June 22 | July 9 |
| Catawbiense 'Boursault' | May 20 | May 31 | June 10 |
| Pauline Bralit | May 9 | May 20 | June 4 |
| Maximum 'Independence' | June11 | June16 | July 4 |
| Lavender Queen | May 11 | May 21 | June 5 |
| April Snow | April 16 | April 26 | May 10 |
| April Dawn | April 13 | April 28 | May 13 |
| catawbiense 'Album' | May 18 | May 28 | June 6 |
| yaku 'Princess' | May 13 | May 20 | June 8 |
| yaku 'Prince' | May 11 | May 24 | June 3 |
| Cunningham's White | April 19 | May 6 | May 26 |
Rhododendron Bloom Data 2020
Rhododendron Bloom Data 2020
| Plant Name | Bud Break | Full Bloom | Bloom Drop |
|---|---|---|---|
| Anah Krusche | May 26 | June 1 | June 17 |
| Goldflimmer | June 7 | June 13 | June 28 |
| Holden | May 17 | May 26 | June 9 |
| Desmitt | May 17 | June 1 | June 10 |
| Janet Blair | May 26 | June 3 | June 10 |
| PJM Elite | April 14 | May 5 | May 19 |
| Roseum | May 26 | June 2 | June 17 |
| Olga Mezitt | April 21 | May 8 | June 1 |
| Vinecrest | May 5 | May 19 | June 4 |
| Summer Rose | June 15 | June 26 | July 15 |
| Catawbiense 'Boursault' | May 18 | June 2 | June 12 |
| Pauline Bralit | May 18 | May 26 | June 2 |
| Maximum 'Independence' | June 15 | June 23 | July 3 |
| Lavender Queen | May 18 | May 26 | June 10 |
| April Snow | April 12 | April 21 | May 10 |
| April Dawn | April 20 | May 5 | May 19 |
| catawbiense 'Album' | May 26 | June 2 | June 15 |
| yaku 'Princess' | May 18 | May 26 | June 8 |
| yaku 'Prince' | May 20 | May 28 | June 8 |
| yaku 'Maiden Mist' | May 23 | June 2 | June 16 |
| Cunningham's White | May 1 | May 15 | May 3 |
| Wilson | June 8 | June 15 | June 25 |
Rhododendron Bloom Data 2019
Rhododendron Bloom Data 2019
| Plant Name | Bud Break | Full Bloom | Bloom Drop |
|---|---|---|---|
| Anah Krusche | May 21 | May 28 | June 10 |
| Goldflimmer | May 28 | June 8 | June 18 |
| Kimberly | April 29 | May 18 | June 2 |
| Desmitt | May 18 | May 28 | June 6 |
| Janet Blair | May 23 | June 4 | June 10 |
| PJM Elite | April 23 | April 30 | May 16 |
| Roseum | May 23 | May 28 | June 10 |
| Olga Mezitt | April 25 | May 16 | May 21 |
| Boule de Neige | May 18 | May 23 | June 4 |
| Summer Rose | June 20 | July 11 | July 18 |
| Catawbiense 'Boursault' | May 28 | June 6 | June 13 |
| Pauline Bralit | May 14 | May 21 | June 4 |
| Maximum 'Independence' | June 18 | June 27 | July 10 |
| Lavender Queen | May 18 | May 28 | June 4 |
| April Snow | April 23 | April 30 | May 9 |
| April Dawn | April 23 | April 30 | May 15 |
| catawbiense 'Album' | May 28 | June 1 | June 13 |
| yaku 'Princess' | May 23 | May 28 | June 13 |
| yaku 'Prince' | May 18 | May 28 | June 13 |
| yaku 'Maiden Mist' | May 23 | June 4 | June 13 |
| Cunningham's White | May 9 | May 21 | May 28 |
| Wilson | June 6 | June 13 | July 3 |
Rhododendron Bloom Data 2018
Rhododendron Bloom Data 2018
| Plant Name | Bud Break | Full Bloom | Bloom Drop |
|---|---|---|---|
| Anah Krusche | May 22 | June 2 | June 17 |
| Goldflimmer | May 18 | June 2 | June 17 |
| Kimberly | April 29 | May 18 | June 2 |
| Desmitt | May 18 | June 2 | June 17 |
| Janet Blair | May 20 | June 2 | June 17 |
| PJM Elite | April 20 | April 29 | June 2 |
| Roseum | May 18 | June 2 | June 17 |
| Olga Mezitt | April 29 | May 18 | June 2 |
| Boule de Neige | May 18 | June 2 | June 17 |
| Summer Rose | June 24 | July 11 | August 10 |
| Catawbiense 'Boursault' | May 18 | June 2 | June 17 |
| Pauline Bralit | May 18 | June 2 | June 17 |
| Maximum 'Independence' | June 17 | June 30 | July 11 |
| Lavender Queen | May 19 | June 2 | June 17 |
| April Snow | April 19 | April 29 | May 18 |
| April Dawn | April 19 | April 29 | May 18 |
| catawbiense 'Album' | May 20 | June 2 | June 17 |
| yaku 'Princess' | May 18 | June 2 | June 17 |
| yaku 'Prince' | June 2 | June 10 | June 17 |
| yaku 'Maiden Mist' | May 18 | June 2 | June 17 |
| Cunningham's White | May 18 | June 2 | June 17 |
| Wilson | June 2 | June 17 | July 11 |