Host an Event Volunteer Join Tickets

Support the plant database you love!

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
3 ratings

Wednesday - April 23, 2008

From: Smithtown, NY
Region: Northeast
Topic: Plant Identification, Shrubs
Title: What is difference between Rhododendrons and Azaleas
Answered by: Nan Hampton

QUESTION:

I am replanting my entire front yard as a native woodland garden (I am on Long Island, NY). I am having a hard time finding native rhododendrons and/or azaleas. I would prefer to remain true to the regions natives, but will any cultivar that I can find locally suffice? Also, I am a bit confused on the issue of rhododendrons and azaleas, They look very different, but have similar Latin names. Can you clarify?

ANSWER:

First, let's clarify the difference between rhododendrons and azaleas. An article from Virginia Cooperative Extension, "Azaleas and/or Rhododendrons", tells us that the main difference is that an azalea has five stamens while a rhododendron has ten. Other differences are: rhododendrons all are evergreen, while azaleas are either deciduous or evergreen; rhododendrons grow larger than azaleas and their blossoms and foliage also tend to be larger. Nevertheless, the botanical taxonomists have put both rhododendrons and azaleas in the same genus, Rhododendron.

The following are the Rhododendron species native to New York:

Rhododendron arborescens (smooth azalea)

Rhododendron calendulaceum (flame azalea)

Rhododendron canadense (rhodora)

Rhododendron lapponicum (Lapland rosebay)

Rhododendron maximum (great laurel)

Rhododendron periclymenoides (pink azalea)

Rhododendron prinophyllum (early azalea)

Rhododendron viscosum (swamp azalea)

You can search in our National Suppliers Directory to find nurseries in your area that specialize in native plants. In a quick preliminary search on nurseries in your area I found Fairweather Gardens in Greenwich NJ that advertised a large inventory of Rhododendron spp. Most nurseries list their plants with the botanical names. If you find any of the species listed above, even though they are a cultivated variety of that species, they should be fine for your area. You would want to avoid using any introduced species (e.g., R. japonicum (Japanese azalea)) or any of the species not native to New York or adjacent states (e.g., Rhododendron austrinum (orange azalea)). You can find a list with maps showing the location of Rhododendron species growing in North America in the USDA Plants Database.


Rhododendron arborescens

Rhododendron calendulaceum

Rhododendron canadense

Rhododendron lapponicum

Rhododendron maximum

Rhododendron periclymenoides

Rhododendron prinophyllum

Rhododendron viscosum
 

More Shrubs Questions

Malpighia glabra for Austin
October 14, 2010 - Dear Mr. Smarty Pants, I am planting native Malpighia in a raised bed that was specially prepared for growing roses (soil and amendments). This bed has been left fallow for several years. Do I need t...
view the full question and answer

Native deer-resistant plants for Virginia
September 26, 2012 - I live in Roanoke/Salem Virginia and want to plant a few plants native to the area along the front yard rock wall. I would prefer they be the same, deer resistant, around 5-6 feet tall max and flower...
view the full question and answer

Small shrub with thorns for Austin
February 08, 2010 - I'm looking for a shade-tolerant 2-3' shrub with thorns, native to Texas (ideally central Texas) - an alternative to Barberry? Does such a plant exist?
view the full question and answer

Pruning a mock orange in Charleston WV
March 30, 2009 - How far back and when do I prune a "Mock Orange" in order to get it to bloom?
view the full question and answer

Holding soil on a bank in Goldsboro, NC
July 25, 2010 - I live in Goldsboro, NC on a small ridge with a very steep bank on one side of our property. What native plants can we plant on the bank to help hold the soil. Also, what would be best to plant on t...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.