The first home I ever owned was a new-build patio home in a new subdivision built on what had been an old almond orchard.  The front yard landscaping that came with it contained a tiny patch of sod, a Modesto Ash and an oleander.  I hired a friend's brother who was a landscaper, to design and install plants and irrigation in the front courtyard, tiny atrium and small backyard.  He interspersed green Pittosporum Wheeler's Dwarf with azaleas, asparagus ferns, dwarf Podocarpus, blue-star creeper groundcover, a dogwood and Double Delight roses in the front courtyard.  It was beautiful year-round, but especially in the spring, when everything bloomed.  The plantings in the backyard were similar.  One of my dogs, a very sweet 40-pound pit bull mix, would literally sit on the “Pitt Wheelers” and eat the azaleas, while I was at work.  I never had to prune anything.  While I found out many years later that all azaleas (and rhododendrons) are toxic, they didn't seem to negatively affect her in any way.  (She also chewed on the 12-volt irrigation wiring without ill effects - she lived to a month shy of 17!) 

Remembering that garden, I drove around Vacaville recently looking for the azaleas and rhododendrons.  The bright colors I saw usually turned up to be roses or geraniums on a closer look.  Azaleas and rhododendrons prefer slightly acidic loam that is consistently moist, but not soggy, good drainage, and morning sun with afternoon shade or dappled sunlight. Their shallow roots also require mulch. Perhaps that is why, when I was driving around, that I found them only in the oldest neighborhoods with mature trees.  

I then started to wonder how to tell the azaleas from rhododendrons or if they are actually the same.  What I learned is that all azaleas are rhododendrons, but not all rhododendrons are azaleas.  

Here are the key differences.  Azaleas usually stay under 3 feet tall, with leaves that are smaller, narrower and pointy and sometimes, deciduous.  The leaves can be fuzzy to the touch.  An azalea's funnel-shaped flowers have 5 stamens or less and the flowers spread out along the stems' length. 

Rhododendrons can get quite tall and to twenty feet wide.  The evergreen leaves feel leathery and have scales on the undersides.  The flowers are more bell-like in shape with 10 or more stamens.  They cluster on the ends of the branches, rather than along the stems' length.  I remember walking by the rhododendrons along the sidewalks in Golden Gate Park, when I was going to school in San Francisco – how tall and wide they were, really a hedge.  

Driving around Vacaville's older neighborhoods will allow some limited rhododendron/azalea viewing, but the best, hands-down, right now is the Mendocino Coast Botanical Gardens in Fort Bragg.  The rhododendrons and azaleas put on a dazzling display in April and May.  The Gardens even have a Rhododendron Show (May 6th and 7th this year) with awards and rhododendron walks on Saturdays, that started on April 1st and run through the last Saturday in May.  If you can make the drive, it is well worth the effort.  The views of the ocean aren't bad either.  Thank goodness for cell phone cameras!