You could certainly argue that the azalea bloom is the symbol of the southeast during spring time. This time of year, yards across the panhandle explode with vibrant colors of this unmistakable flower bloom. Even though Florida’s azalea plants put on a spectacular flowery show, most of us pay very little attention to their management at this time of year. However, the kind of care azaleas receive in late spring and summer can have an effect on the bloom production for next season. There are some management measures that can be done during this time to ensure that you have a bountiful azalea bloom next spring.

Credit. Carolyn Wildes, UF/IFAS.

Credit. Carolyn Wildes, UF/IFAS.

Chlorosis, a condition that causes leaves to produce insufficient chlorophyll, is the most common problem with azaleas this time of year. Fortunately, this is easy to recognize and correct. Chlorosis shows up as yellowing in between the veins of leaves, the veins stay dark green. It’s caused by lack of available iron in the soil.

To correct chlorosis, add aluminum sulfate to the soil. The addition of ¼ to a ½ pound per square yard of soil surface should suffice. Broadcast the aluminum sulfate over the soil surface and add a layer of mulch. It’s important to remember that you should not apply aluminum sulfate more than once a year. More applications will cause detrimental effects to the plant. Other chemicals that are useful in correcting iron chlorosis in azaleas are ordinary agricultural sulfur, ferrous sulfate and chelated iron compounds. Each of these chemicals have different application directions, so be sure to read the labels for direction of use.

Proper watering is also imperative. Generally, established plants should receive ¾ – 1 inch of water every 10 days to 2 weeks during dry periods to wet the soil to a depth of 10-12 inches. When the weather is hot and dry, azaleas need soil saturation in the root zone once a week. Azaleas have shallow feeder roots that dry out very quickly if the soil is dry. Remember, soil with a sufficient amount of organic matter holds moisture better than sandy soils, and will require less watering. Also, a mulch layer helps to reduce evaporation and keep the soil cool and moist.

Pruning your plants should be done in late spring. If you prune later in the year, there’s a good chance you may reduce or eliminate flowers for next year. Usually it’s best to prune right after flowering.

As for fertilizer applications, frequent and light applications are necessary in Florida’s sandy soils. Acid-forming fertilizers like 12-4-8, 15-0-15 or ammonium sulfate should be applied in all four seasons. Apply approximately ¼ pound to a mature plant, or ¾ to 1 ½ pounds per 100 square feet.

Following these recommendations will help secure your rich bloom season for next year.

For more information please see:

Azaleas at a Glance

Florida-friendly Landscaping

 

Ray Bodrey