By Chad Diller at Tomlinson Bomberger
Azaleas are a widely-used traditional plant seen in landscaping both on commercial and residential properties. One of the trends in modern landscape design is to steer away from azaleas as many landscape designers and the landscape companies that install shrubs like azaleas have found that these plants have a high mortality rate in most landscapes. As a company that not only designs and installs landscaping, but also maintains it with professional solutions for tree and shrub care and landscape maintenance, we have found it’s more common to find struggling azaleas than ones that are thriving.
There doesn’t seem to be much middle ground. Azaleas either seem to be untouchable or unsuccessful. An easy solution could be to find an alternative flowering shrub. However, if you have a property with azaleas that you’d like to maintain or if you are passionate about adding this plant to your landscaping, be sure to understand that the success of growing beautiful azaleas hinges on these factors:
Insects: Azaleas are prone to lace bug damage. These little insects are tough to spot and even tougher to spray for. They feed on the undersides of leaves, leaving a stippled appearance and diminishing the plants ability to properly photosynthesize. Most property owners will not know the source of their dull-colored leaves and this issue will go untreated for years. This is actually an easy problem to solve. Have a tree service perform an annual soil-applied systemic insecticide for this pest. It will last all season long to control lace bugs on azaleas.
Fertility: Azaleas don’t have a large requirement for fertilizers, but there are common occasions that call for it. Moderate amounts of nitrogen will help winter tolerance. Phosphorus will favor early production of flower buds. Magnesium and Iron may also help with leaf color. To figure out if the soil around your azaleas is ideal, take a soil test and have it analyzed and make the needed amendments.
Soil pH: If your soil pH is 4.5-5.5, your azaleas will be able to better uptake nutrients. Most of the soil in our area ends up being slightly higher than that. Taking a soil test and adding the recommended rate of sulfur to beds can help lower the pH to ranges that are ideal.
Moisture: Azaleas like to have moist, well-drained soil. That may seem contradictory at first glance, but it means they need frequent watering but the soil needs to not stay waterlogged. Otherwise, root systems will rot and the plants will fail. Dig a 12″ hole at multiple sites in your landscaping beds. Put a tape measure in it and secure it so it won’t sink later. Fill the hole with water and measure the initial depth. In 15 minutes, remeasure the depth. Good drainage will be at 4+ inches per hour. If you’re not getting that type of drainage, you’re going to need to find a different plant to install or add materials such as organic matter, sand, or gypsum. An expert landscaping contractor with certified horticulturalists should be able to do this for you.
Sun Exposure: Azaleas will adapt, but they are not a good plant for extremely hot, sunny areas. The ideal location will have variable shade, allowing some sunlight to reach plants, but still remain in mostly shaded conditions the majority of the day, particularly in the afternoon.
Winter Damage: Azaleas don’t have extremely strong branches, so whenever possible, try to reduce the amount of snow that gets piled on them in winter. If your azaleas are varieties that are evergreen, help to reduce winter damage by irrigating them in the fall if needed, and also applying winter protection sprays during the late fall through winter to help moisture to remain in the leaves.
If you have azaleas on your property that are in need of help please don’t hesitate to contact us.