The combination of brilliant flowers, dark green foliage, and soft texture makes the azalea more colorful than most any winter hardy flowering shrub in the Gulf Coast area. When they are planted correctly and in the right location, they are very easy to grow.

Azaleas need good drainage, so an elevated bed is very important in our area. Most azaleas do best in semi-shaded areas. This is especially true of Kurume and dwarf varieties. Some of the Southern Indica varieties, the larger growing azaleas, and the variety Fashion will grow in full sun if properly planted.

Bed Preparation

To prepare the bed, first, spade up the existing soil to a depth of four to six inches. If possible, do not remove the existing soil, but add the following soil amendments per 100 square feet of bed area to build up the bed level at least 4 inches:

14 bags CALLOWAY'S Landscaper's Mix

4 lbs.of Ironite (acidifier)

20 lbs. of Gypsum

By the time these items are thoroughly mixed into the soil, it will elevate the bed area properly and provide an excellent growing medium for your azaleas.

When planting, before removing the azalea from the container, water it thoroughly. Allow water to be absorbed, then remove from the container. After removing the azalea from the container, OPEN AND SPREAD THE ROOT BALL OF THE AZALEA using a sharp knife or a hand trowel. Loosening and spreading the roots encourages new root growth. Failure to loosen and spread roots adequately could contribute to the loss of the plant. Set the top of the root ball at least one and one-half to two inches above bed level and pull up enough soil to barely cover the top of the root ball. Water plants well using applications at two to three week intervals during the first several months. Developing a good root system is one of the main keys to being successful in azalea gardening.

Top Mulching

Top mulching your azalea bed with a two-inch layer of pine bark mulch or decorative bark will aid in growing azaleas in three ways:

1. It controls many weeds and grasses.
2. It protects the root system during hot and cold weather.
3. It aids in retaining moisture.

Azaleas may be planted any month of the year, even while flowering. Azaleas require frequent, thorough watering during their first 12 months in the landscape. Since azaleas have shallow surface roots and are elevated when planted, they may require daily watering in extremely high summer temperatures.

REMEMBER: AZALEAS PLANTED CORRECTLY AND THEN PROPERLY CARED-FOR WILL GIVE YOU MANY YEARS OF PLEASURE.

There are many azaleas in the Houston area which are now over fifty years old. A layer of new mulch one to two inches thick should be added to the azalea planting each year to compensate for organic breakdown in the bed.

Pruning

Pruning should be done immediately after blooming, not later than mid-June. Cut out any dead branches you may find. Trim each azalea plant to the size or shape you desire. Exceptions to this will be the Macrantha and Fashion azalea varieties. Macrantha Azaleas are considered everblooming. Remove any long shoots (water sprouts) necessary to maintain a well-shaped plant any time during the year. Fashion Azaleas flower in the fall and spring, so prune them only once after the spring-flowering period to the shape desired.

Fertilizing

On established plantings, fertilize with Calloway's Azalea Fertilizer immediately after blooming in the spring. Apply 1/4 cup of Calloway's Azalea Fertilizer per 1 1/2 feet of healthy, bushy plant height. (For other circumstances consult a Cornelius Texas Certified Nursery Professional.) Apply from 4 inches of base of plant to dripline. Fertilize very 4 to 6 weeks through the summer. Calloway's Azalea Fertilizer has been developed exclusively for Cornelius customers in the Houston area. Broadcast the fertilizer over the entire azalea bed area at the rate of four pounds per 150 square feet. It is not necessary to remove the top mulch when you fertilize. Scatter on top of mulch and water in. The fertilizer will reach the root system gradually. If an azalea has been planted or transplanted in the three months preceding fertilizing time, apply fertilizer at recommended times, but at half strength.

Iron and pH

In understanding iron reactions in azaleas, we need to understand its relationship with the soil pH, or soil acidity.

The acidity or alkalinity of a soil is based on its hydrogen ion concentration and is expressed as pH. The pH scale is graduated from 0 to 14; a pH of 7.0 is neutral, with reactions above 7.0 being alkaline and below 7.0 being acid. The degree of alkalinity or acidity increases or decreases by 10 times the previous level of each whole number change. Therefore, a pH of 5.0 is 10 times more acid than a pH of 6.0, and 100 times more acid than a pH of 7.0. (This means that if you have a soil that is very alkaline, or very high pH, it will take more acidifier to move the pH initially than if your pH was closer to neutral. This is due to the highly alkaline condition of the soil offsetting the acidity of your amendment.)

More iron is required than any other micronutrient. It has often been considered both a macronutrient and in a category by itself. Most soils contain iron, but some conditions make the iron unavailable to your plants. An improper relationship between soil pH and availability of iron causes iron chlorosis, or fading of the normal green of the youngest leaves making them yellow. Beginning with a pH of 5.0 to 6.0, the iron in your soil becomes progressively less available as you approach the most alkaline point of 14.0.

As many soils in Houston tend to be more alkaline, your plants may be exhibiting iron chlorosis due to the higher pH of your soil, not necessarily from a lack of iron in your soil. Usually, an application of 1.5 pounds of ground sulfur, not dusting sulfur or aluminum sulfate, added to 100 square feet will lower the pH about one half a point. It is advisable to retest after each adjustment before additional applications are made. If a soil test reveals that iron is definitely deficient, then you can apply iron either as a spray or as a soil application. In alkaline soils, though, some iron would be immediately rendered unusable. It is important to choose the correct form for your problem.

When iron is combined with certain organic compounds, it forms a stable carrier known as "chelate". Chelated iron is not easily broken down in the soil and is less prone to leaching. Any of the chelated irons would be effective as a foliage spray. Chelated iron is particularly effective when applied to soils and would have a longer residual than water-carried types, like iron sulfate. Although iron sulfate may be more readily obtained, its major drawback as a foliage spray is the typical browning discoloration that results if it is accidentally sprayed onto walks or buildings adjacent to the sprayed areas.

If your soil exhibits the proper pH range of 4.5 to 6.0 for azaleas and your plants show the yellowing of iron chlorosis, then an application of iron may be needed. Either iron sulfate or the chelated irons can be applied, either to the soil or to the foliage as a spray. Remember: Soluble irons have no long-term effect due to leaching and therefore require more frequent application.

We at Cornelius Nurseries recommend that if your pH is above 7.0, add sulfur at the rate of half a pound per 100 square feet. Mix CALLOWAY'S Landscaper's Mix or peat moss into the soil. Retest in 6 weeks. If your pH has been reduced sufficiently and your plants are still exhibiting iron chlorosis, use a chelate form of iron either as a spray or as a soil treatment. Soluble iron sulfate will work, but will have little residual effect. You will need to re-apply it in 4 to 6 weeks. You may also apply a granular iron product.

If your pH is below 4.5, use Chelated Iron either as a spray or a soil treatment.

WARNING:

All iron products can stain concrete, brick wood, plaster, stucco, and all porous and painted surfaces. Please avoid over spraying liquid iron and overspreading of granular iron. Sweep up any granules or powders before watering. If you accidentally over spray, wash off immediately. Most stains can be removed by a weak application of chlorine.

Insects

Azaleas require very little spraying but should be sprayed each spring after blooming with an appropriate pesticide to prevent and control spider mites and lace bugs. Spraying your azaleas 2-3 times at 30 day intervals during the growing season will keep your plants healthy.

If you have any other questions about planting azaleas please contact a Cornelius Texas Certified Nursery Professional. We're open seven days a week.