JARS v41n4 - Shear Magic With Azaleas

Shear Magic With Azaleas
Franklin H. West, M.D.
Philadelphia, Pennsylvania

With the surname of Morrison, it seems almost inevitable that azaleas would be favored by the plantsman of the house. And favored they are, as the accompanying photograph demonstrates. The remarkable thing about the azalea garden at 452 Brookhurst Avenue, Narberth, PA, is that it has been in existence for fifty years and has looked almost the same for all of those years. Each spring's colorful display is nearly an exact replica of the preceding one.
How is such a thing possible? Evergreen azaleas in eastern North America are greedy consumers of real estate (and air space) but not so in James E. Morrison's garden. There must be a secret to controlling an azalea garden that keeps the bushes within bounds and at the same time guarantees a spectacular flower show year after year. Jim Morrison tells us that the secret is in the timing of the annual shearing he gives his plants, shortly after they have finished blooming.

Sheared azaleas
Photo by Franklin H. West

Jim started his azalea garden in 1936 from cuttings gleaned from friends and neighbors. (This was just a few years before Ben Morrison's Glenn Dale azaleas were released for distribution.) He rooted his cuttings by sticking them into the humusy soil beneath other shrubs in his 50' x 150' property. Their shade provided enough protection for the cuttings to allow them time to root. He just watered them in and let the good Lord take care of them! After he retired in 1966, he had more time to help the Lord out, but this was only necessary in times of severe drought when he gave his azaleas water.
He uses no mulch, no sprays, no fertilizers. Each autumn he does pick out the fallen leaves that get wedged in the plants. Other than this, no maintenance is necessary, because the azalea growth is so densely branched that weeds haven't got a chance to survive.
Jim decides to shear the plants when the new growth has put out from four to eight new leaves or when the shoots are from " to 2" in length. This can happen as early as June 10th or as late as early July in this southeastern Pennsylvania garden. He both shears and shapes the plants at the same time once and only once. He employs electric shears for most of this task, but for the difficult to reach spots he uses a hand clipper rigged on the end of a pole.
Freed from the apical dominance of the growing tip, each clipped shoot then produces one to five side shoots. Each one of those produces flower buds by late August. No wonder his plants are covered with flowers! They have 2 to 3 times more flower buds than an un-sheared azalea of the same size.
Jim observes that in most years all of his plants bloom at once, having their peak about Mother's Day. This reflects the early midseason blooming times of his original selections - mostly 'Ledifolia Alba' (syn. 'Mucronatum'), 'Snow', 'Hinode Giri', 'Hino Crimson', 'Pink Pearl' and 'Coral Bells'. In the occasional year when the bloom is less than perfect, he has, in each instance, found that the previous autumn was unusually frost free into late November, followed by a sudden deep freeze in December that nipped all the flower buds that were not fully dormant.
Jim Morrison has given us a fine example that shows how much one can do with azaleas on a small plot of land. His shearing secret should help you do every bit as well, wherever azaleas are "at home".

Dr. West serves on the ARS Board of Directors as Director At Large. He was the co-editor of the ARS sponsored book, Hybrids and Hybridizers.