IN THIS ISSUE
Rhododendron degronianum ssp. yakushimanum
April Web Specials
One species from Japan that has made a very big impact on the rhododendron world

 

Greetings!
 
In this newsletter I will be discussing the rhododendron degronianum ssp yakushimanum, or commonly called "Yak". This unique species has transformed the rhododendron world, offering plants of smaller stature with hardy qualities for colder climates. Learn about the many hybrids that have come from this species and which ones you might want.

R. degronianum ssp. yakushimanum
 
Native to one small area on the northern part of  Yakushima Island, Japan, this unique rhododendron species grows on rocky slopes among Cryptomeria and other small trees. It is quite hardy, with reports that it can take -20 deg. F. The plant is considered to be a dwarf, and will form a dense mound 2 ft tall and 3-4 feet wide in 10 years, but over time it can become 6 ft tall, but this will take 50 years. Yearly selective pruning could keep the plant smaller if desired. This rhododendron used to be its own species, R. yakushimanum, but now it is been designated a subspecies of R. degronianum. It was first described by Nakai in 1921, and named for the island it is found on. 



 
 
  


This 15 year old specimen is only 18 inches tall and 30 inches wide.
Foliage Characteristics

The leaves of R. degronianum ssp. yakushimanum have down curving edges, are somewhat shiny and have a nice coating of wooly, tan indumentum on the undersides. No, this is not a disease...it is a prized feature! This is a trait that should be admired and not something to 'get rid of'. Once you accept that this indumentum is prized by collectors, you will begin to like it.  
When the new leaves emerge, it often looks like a bunch of rabbit ears...silvery and fuzzy. How adorable! You will want to pet them. As they open, they will have a white dusting on top and on the stems as well. If you can rub it off, then it is the prized indumentum. If you cannot rub the silvery coating off, then it may be damage to the leaves caused by thrips. This is a problem. 
Once the new leaves have opened fully, the dusting will be at its peak, and as the weeks go by, some of it will disappear. By the time most of it is gone, you should see flower buds the size of marbles forming. This species will often make a flower bud on each stem resulting in a real show the following spring, covering all of the leaves with lovely light pink flowers that fade to white.
R. degronianum ssp. yakushimanum Hybrids
 

There are many hybrids of R. degronianum ssp. yakushimanum, so we will shorten the the name to 'yak'. Hybridizers realized early on that the qualities of this species could be useful to create other, more colorful hybrids. So they have used the strong colors like red and purple to try to end up with some cultivars with more color in the flowers.  Most lack the intensity desired, but are still quite nice. 

 

'Yak Hybrids'
 
 
R. 'Aloha' has light pink flowers and makes a dense mound 4-5 ft. wide and 2 ft tall. Created by Dr. Carl Phetteplace of Leaburg, Oregon, USA, and registered in 1973. It is a cross of Vulcan, a rich dark red with yak. As you can see, the yak genes are dominant resulting in a light pink.  
 
 
 
R. 'Amity' has darker pink flowers and will be a mound 3 ft. tall and 2 ft tall. Hybridized by James Elliott of Astoria, Oregon, USA, and registered in 1970, this was a cross of a dark red with  yak.  
 
 
 
 
 
 
 
  
 
R. 'Anne Cree' has larger flowers with ruffles and a strawberry red blotch in the upper lobe of each flower. This plant will grow 3-4 ft tall and 4-5 ft wide over time. The plant was created by Elsie Watson of Kirkland, WA, USA, and registered in 1985. Here, she crossed yak with R. 'Chevalier Felix de Sauvage', an old timer dark pink with a strawberry blotch.
More 'Yak Hybrids'
 
R. 'Cupcake' was done by the Thompson Nursery of Waldport, Oregon and registered in 1971, and is a  hybrid of yak with an orange flowered hybrid called 'Medusa', thus there is a little bit of 'orangey' flavor to the flowers of this cultivar. Flowering heavily every year, 'Cupcake' is just that...a cupcake with peachy/pink frosting. 
 
Interestingly, this yak hybrid R. 'Silver Skies' is the same cross as R.'Cupcake' above, but what a different outcome! Hybridized by Frank Fujioka of Washington State, and registered in 1982, this plant has very shiny leaves and lovely bi-colored flowers. The plant will grow to be 2-3 ft tall and 3-4 ft wide over time. 
 
 
 
 
 
 
 
R. 'Patriot's Dream' is a hybrid between R. 'Carmen', a rich blood red, and yak. The plant is a small grower, becoming 15" tall x 2 ft wide over 10 years. The flowers are a true red in loose clusters. The leaves are the best part, being very small and shiny, making it one of the best looking plants in the garden.
More 'Yak Hybrids'
 
R. 'Fantastica', from the Hachmann Nursery in Germany is quite a sight to behold in early May. The flowers are light pink in the center and almost red on the edges. The plant is somewhat larger, growing to 4-5 ft tall and a little wider in 10 years. This cross of R. 'Mars' x yak has been done many times, but I would say that R. 'Fantastica' is one of the best results. 
  
  
 
R. 'Yaku Sunrise', another picotee flowered hybrid has the added pale yellow throat, giving it a "sunrise" glow. The plant will make a tight mound 3 ft tall and 4 ft wide and can take full sun. Created by Ben Lancaster Lancaster of Camas, Washington, USA, and registered in 1965. The parents are R. 'Vulcan's Flame' x yak.   
 
 
 
 
R. 'Lavender Haze' is one of the best foliage plants that we grow. The leaves are a shiny dark green and the plant is full and lush, always looking handsome in the landscape. The flowers have a light lavender shade and cover the plant in May. 
Last but not least is R. 'Seaview Sunset' created by Frank Fujioka of Washington State. Here is a 'yak' hybrid with really different flowers. Opening red-orange, then turning a light yellow with a bright orange edge, this is a 'must have' in this group of hybrids. The foliage is very dark-green and holds for 3-4 years, creating a dense fully clothed plant. You can expect it to grow to 3-4 ft tall and 4-5 ft wide in 10 years. Luscious! 


   
For the month of April we will have many assorted plants ON SALE for 25% OFF. 

March's Conifer Special 
will be over on Monday, March 31st.