Growing Azaleas

Lisha Utt
Frederick County Master Gardener Program

Azaleas are great plants and certainly one of the most popular in Maryland landscapes. All azaleas belong to the genus Rhododendron. Evergreen azaleas are in the subgenus Tsutsusi and deciduous (leaves drop in the fall) azaleas are in the subgenus Rentanthera. There is a large variety of azaleas with differing habits, sizes, colors and bloom times --- an azalea for every gardener.

Azaleas like moderate temperatures and are cold hardy to zones 6 to 8. They prefer a shady sight, such as the north or east side of your home. It does not have to be dense shade, filtered sunlight or a sight that receives morning sun and afternoon shade will be fine. Some varieties, especially deciduous types can do well in full sun. Azaleas also like to be protected from the winter winds by a building, slope, evergreen trees or shrubs. This helps them avoid leaf scorch or stem bark splitting.

Azaleas grow best in slightly acidic soil (pH 5.5 - 6.0) that has good drainage. Given the heavy clay soil in our area adding amendments to the planting bed is important. Azaleas can be planted or transplanted in the fall or the early spring. But should be adequately watered whenever they are planted. It is more beneficial to provide a deep soaking on an infrequent basis than regularly sprinkling the surface.

To plant an azalea, dig the hole 2x the width of the nursery container or root ball and only as deep to keep the plant stem at the same level as it was growing in the nursery or in your yard. It is better to plant a little shallow than too deep. Azaleas do not necessarily need to be fertilized when they are planted. If you do decide to fertilize do so before mid summer to avoid causing new growth that may be killed in the winter. Azaleas should be pruned soon after they bloom to avoid cutting off next year’s flower buds.

Now let’s talk about your azalea. From your description it seems like your azalea loves it’s location --- a sheltered not-so-sunny spot. I would not recommend moving it to a sunnier location. I f you do decide to move your azalea it would be okay to transplant it now or wait until the spring.

Just remember that whenever you move it you will need to water it adequately to help it through the transition. The rains appear to be coming back as this Fall progresses, but if the extreme dryness continues you might want to bear in mind any water restrictions in your area before making the move. I would not recommend fertilizing the plant given the cold weather that is certainly around the corner.

I hope this information is helpful. Azaleas are beautiful plants and given the conditions they prefer, are easy to grow. Spring just wouldn't be spring without them. Best of luck and happy gardening!!!

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