Pine trees with moderate filtered shade give ideal protection for azaleas. However, very heavy shade throughout the day may reduce flower production and result in weak growth. Evergreen trees or tall shrubs with low branches make good windbreaks and attractive backgrounds for an azalea planting. Shallow-rooted trees, such as oaks, elms, and maples, may compete with azaleas for moisture and nutrients. Soil conditions should be considered in selecting a planting site.
Azaleas require an acid soil pH to grow properly.
Check the soil pH of your site before you buy azaleas. If the pH is above 6.5 you can expect to spend additional money and effort to maintain a pH in the proper range for plant growth. It may be to your advantage to consider other kinds of landscape plants for that site. However, artificial raised beds can be created by adding pine bark or peat moss to improve drainage and lower pH. These beds should be 10 to 12 inches deep. This depth provides an artificial environment similar to a large container.