By Mike Raley
Our friend Rufus delights in discussing his love for Rhododendrons. Rufus, after all, is a learned man with deep North Carolina mountain roots and the rhododendron is a fixture on the sides of hills in the higher elevations of the west, from Tryon to Sparta and on to Murphy. Some of our listeners tell us on the WPTF Weekend Gardener that they have trouble growing rhododendrons. But we grow rhododendrons all over the state and they are actually easy to grow. Many of the rhododendrons we grow are azaleas. That’s right; azaleas are, according to the girls and boys at NC State, in the genus Rhododendron as a subgroup. But not all rhododendrons are azaleas.
I don’t remember any rhododendrons in my hometown down east when I was growing up. There were plenty of azaleas, some decades old. However, I do remember a large, healthy specimen growing in a corner of my wife’s childhood home on a beautiful farm in Chatham County. I fell in love with that farm not long after I fell in love with Melissa. Anyway, this rhododendron lived for decades in what appeared to be its “happy place”. The blooms were lavender and seemed very elegant and welcoming at one of the home’s back entrances. The plant deteriorated over the last ten years, but it made me consider the gardening saying, “the right plant for the right place.” That protected corner against the house in the morning sun must have been it. That must have been it!
Where do rhododendrons thrive? We’ve established they are at home in the higher elevations of our extraordinary mountains. They seem to grow well in what gardeners refer to as dappled shade in moist, but well-drained acidic soil. To me, that means on a slope in your landscape in an area that doesn’t have a lot of root competition with that sprinkling of shade away from the direct afternoon sun. In a spot with good drainage. No wet feet!
Now one of the problems we face in the central part of the state is the clay soil. Rhododendrons don’t like that although they are generally easy to grow. They prefer the amended sandy soil of the east or the loamy soil of Rufus’s mountain home. If you have red or beige clay then using some type of organic matter is a must. Black Kow or Daddy Pete’s will work well. Rhododendrons should be planted in a shallow hole that is twice the size of the root ball. I know that’s a lot of work, but it’s always worth it. To paraphrase my late predecessor John H. Harris, don’t place a $50 plant in a $10 hole. If you can find a suitable rhododendron in the fall, that is the time to plant it.
Many of us seem to love to fertilize plants. This certainly makes sense for most plants, but sometimes we really overdo it. As we mentioned, add some organic matter as you plant your rhododendron. Some of my gardening friends suggest adding some Biotone from the Espoma company. This along with the organics will have the nutrients you need when you plant. Add a light dose of Holly-tone in spring. Just like with your azaleas, don’t overdo it.
Another chore we seem to be fond of is pruning everything in sight. Sometimes I get the itch myself, but just make sure to prune rhododendrons right after they bloom.
As long as your rhododendron doesn’t get root rot or a related problem from soggy soil, the main problems you might encounter include: rhododendron borers, lace bugs, weevils and certainly the proverbial deer herds.
Finally, if you want native rhododendrons, plant the Catawba or the Carolina varieties. But plant breeders have developed many varieties that are more heat tolerant and might have other characteristics you might prefer. Read the attached plant description prior to buying. As always, check with the experts at some of our extraordinary nurseries all over North Carolina. Hey, and you can always call the Weekend Gardener, right?