Rhododendron obtusum is the mother species of the Japanese Evergreen Azalea that has various natural varieties as the Kurume (R. obtusum japonicum), the Torch (R. obtusum kaempferi), the Amoena (R. obtusum amoenum) and others. Arthur T. Viertel in his "A Pictorial Guide to the Ornamental Woody Plants of the United States, Exclusive of Conifers" from Syracuse University Press, 1970 listed these east Asian shrubs as Azalea rather than Rhododendron and has the species name in the feminine ending in (a); so it would be Azalea obtusa. If I had my way with the huge genus of Rhododendron I would divide it into three genera of Rhododendron and Azalea and something like (Pseudoazalea) or (Azaleoides) to represent these evergreen to semi-evergreen east Asian shrubs that have tiny leaves; that generally grow more bushy with stiff branching; having less stout stems and slender twigs; and that really don't bear yellow or orange flowers, like the generally taller, more upright Deciduous Azaleas with larger leaves that get fall color and have stout twigs and stems. I posted photos of a really old Japanese Evergreen Azalea shrub that was about 10 feet high and wider in a rounded form that used to bear white flowers in May in Wayne, PA, west of Philadelphia, that I am designating as being close to the mother species, if not her in reality. I took her out in 2014 as I wanted something else and I was tired of so much Azalea Lacebug all over her. The newer cultivars of these azaleas are generally 3 to 5 feet high and a little wider. There is such a huge number of mostly Japanese selections that have become many, many cultivars of a big range of various shades of color from white to pink to red to purple. Actually, about 10 or so of the most popular cultivars are offered at most conventional nurseries and big box garden centers. They are relatively cheap plants and the common homeowner considers these as the "azalea." I don't. These kinds of azalea often grow stiffly so that I have gotten scratched up by them white pruning them for customers. They do better to not be planted in full sun and windy conditions as is often the case, as they discolor to an ugly purple-brown in winter that way and get more Azalea Lacebug, though they generally survive. I consider these plants as way over planted and I wish the general gardening public would open up to a range of better species to use in landscaping one's yard. They make fantastic greenhouse florist plants!

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