This group of plants includes Rhododendron, Azalea, Mountain Laurel, Leucothoe and Pieris to name a few. They have leaves that remain on the plant year-round where Evergreens like Pines and Spruce have needles.
These plants natively grow in woodland conditions providing dappled sunlight and organic rich soils. They are shallow rooted and prefer a well drained soil with adequate moisture throughout the season. In choosing a site for them, look for morning sun with afternoon shade. When planting in a woodsier location make sure you provide an adequate hole easily twice the width or more of the root ball. This will provide enough soil to establish a root system as tree roots are typically numerous in these type of settings. In other locations where poor soil is encountered with lots of rocks, or in heavily compacted clay soils, you must add and or replace the soil with an organic rich combination of topsoil with compost in a ratio of 1:1.
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Another planting method that can greatly support success is planting above the existing grade. By providing a surrounding soil medium that gradually tapers from the plant to the existing grade you improve your drainage. These plants are shallow rooted so they should be mulched preferably with a bark mulch to help retain moisture, control weeds and for aesthetics. Cultivation should not be done around their roots such as planting annuals as this can damage their shallow root system.
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For the first couple winters it can help to offer some protection such as Wilt-pruf which you spray on the foliage to retain moisture and prevent desiccation. This should be done in the fall and again in the early spring.