• George R. Lee

Rhododendron Buying, Planting, Location, and Care


An outstanding compliment to any landscape is the beautiful show case Rhododendron. There are more than 900 species in the Rhododendron genus which vary greatly in size, color and temperature zone tolerance. In Michigan the zones range from 4-6. Make sure you know the planting zone where you live before selecting your rhododendron species.


If you're not an expert or lack a masterful "green thumb" I suggest contacting a professional arborist or horticulturist before selecting and making your purchase. A true professional will want to make a site visit with you. This visit will include addressing the right plant for the right location. Other matters to address will include sun/shade balance, pH levels, soil content, drainage, impact on the landscape at maturity, and discussion regarding annual care (if and where needed).


Rhododendron come in many colors and sizes. Pink, white, red and lavender are some of the more popular colors found in the landscape. You can also grow plants that at maturity are just 2-3 ft tall and there are those that will grow or climb up to be as tall as 25 ft and sometimes even taller.


In zones 3-6 rhododendron require approximately 5-6 hours of sun light a day. The breeze and sunlight helps to reduce disease issues (such as powdery mildew) to a minimum.



In many areas of Michigan it takes more than simply digging a hole to see these awesome plants thrive and shine. Heavy clay soils which are poorly drained will not provide the environment needed for a rewarding, long term, healthy life for any rhododendron. Prep work is EVERYTHING!


For any acid loving tree to thrive and reach it's full potential the soil pH should be somewhere between 4.5-6.0. If you were looking to grow rhododendron in North Carolina you'd stand a very good chance of your existing soil pH being just right with very little soil amending needed. However should your landscape be located in southeast Michigan you could find your pH to be something between 6.8-7.4. With a pH in the 7.0 range you will need to take many steps to enhance your soil to best serve the needs of any species of rhododendron (in fact for most acid soil loving trees and shrubs).


Other factors one should consider when planting rhododendron include:


  • Location

  • Shade and sun

  • Soil pH

  • Drainage

  • Pruning - the when and how

  • Fertilizer - yes or no

  • Soil amending - when and how often

  • Herbicide and lawn fertilizer concerns

  • Irrigation issues and proper watering methods

  • Pest threats such as vine weevil, whiteflies, leafhoppers, scale insects, aphids, bud blast, rust, petal blight, root rot and induced chlorosis.

If you truly want a success story for your rhododendrons, you should contact an arborist. The professionals at Branch Tree Service, Inc. in Warren, Michigan have years of success stories to share with you of how they have helped so many customers enjoy years of beauty from their rhododendron. This article can also be used as a guide when planting azaleas or japonica.

For further help with your next acid loving planting project, feel free to contact the expert arborists at Branch Tree Service.