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AZALEA

AZALEA TIME DOWN SOUTH

East Texas is blessed with the climate and soil to grow azaleas, one of the brightest of plants. As a sub species of the rhododendron family, it has adapted to our mild winters and warm summers. The acidic, sandy soils of east Texas are ideal for this prolific bloomer.

Nurserymen have developed many varieties and each has its own growth habit and color. They look best when left to their natural shape so select a plant that will fit your landscape need. Tall varieties will grow to more than eight feet. Medium sizes will reach five feet, while the smaller plants will grow to three feet. The spread of the plant must also be considered since azaleas mature rapidly.

The blooming periods of azaleas vary from early (March - mid April), mid-season (mid April - May), to late (May - June). If a color, or combination of colors is used in the same bed, make sure the blooming periods coincide to maximize impact to the landscape.

Location of the planting is important because azaleas do best with exposure to eastern light or filtered shade. If these conditions are not possible, then select azaleas that have a thicker leaf which will tolerate more sun. In all cases, elevate the bed to give them good drainage, and mulch to protect the shallow roots from summer heat.

Feed after last bloom drop with Azalea-Camellia food, then lightly once a month during growth.

Paul Ferguson, Smith County Master Gardener
Texas AgriLife Extension Service


AZALEA CARE

Spring time is azalea time and here's how to help them repeat their blooms next year.

If your plants are in need of some pruning for shape or size, wait until the blooms have fallen before attacking them with your pruners. If there are dead branches, cut them back to green wood and inspect for freeze damage indicated by bark splitting.

Azaleas are tough plants so prune as needed. For neater plants, pick off spent blooms. Wait to feed after the pruning. Use an azalea fertilizer and follow the label recommendation.

If these are new plantings and you are unfamiliar with azaleas, go to a nursery and see the plants in bloom. Select a flower color you like, but don't forget leaf shape and color. Many varieties have leaves that turn bronze in the fall, adding color to a normally bland winter landscape.

If you have a special place and size in mind, then ask about their growth habits. Don't try to control a large variety in a lows small area. It won't work.

To help keep your plants looking nice, use an azalea fertilizer after blooming and follow the label recommendations. Be careful of using a fertilizer too high in nitrogen as is common with many lawn fertilizers since this can burn and even kill the bushes. Azaleas benefit from a more acidic fertilizer combination than other plants, so a slow release fertilizer made especially for azaleas can really help keep your bushes healthy.

Have you noticed that the leaves of your azalea bushes look silvered or white, not dark green? Look on the underside of the leaf and if you see small dark spots, this a sure sign of the azalea lace bug. The azalea lace bug is a small, nearly invisible, flying insect common in east Texas. Severe infestations can do a lot of harm to azaleas. If the lace bug population is small and little damage is apparent, wash the bugs off with a strong water spray from a garden hose. When the infestation is light and water doesn't seem to work then try using an insecticidal soap as the first step in chemical control. For a heavy infestation, use products containing dimethoate (Cygon), acephate (Orthene), carbaryl (Sevin), or malathion. Repeat at 10- to 14-day intervals, if necessary, to maintain effective control.

Paul Ferguson, Smith County Master Gardener
Texas AgriLife Extension Service


AZALEA CARE AND FEEDING

Now that spring is just around the corner, many people start wondering when they should fertilize their azaleas. The best time to fertilize azaleas is right after they finish blooming. Apply a slow release nitrogen fertilizer to stimulate good growth for the spring and summer. About eight weeks later, apply an acid-type fertilizer labeled "for azaleas, camellias, and gardenias." Reapply the azalea fertilizer about every six weeks until the middle of September to stimulate good bud set for the next year's bloom period. Apply small amounts each application, lightly scattering over root area.

Yellowed leaves with dark green veins are characteristic of iron deficiency. If your azaleas start showing signs of iron deficiency, there are several ways to treat them:

  1. Apply a soil acidifier such as sulfur to allow iron that is already in the soil to return to an available form.
  2. Apply a chelated (treated to maintain solubility) iron material or copperas (iron sulfate) to the soil.
  3. Apply a granular iron to the soil.
  4. Apply a foliar spray of an iron compound; this must be done during the growing period and will have much shorter residual action than the soil applications.

If you need to prune your azaleas, do so after they finish blooming. Minor reshaping is usually all they will need. And remember not to prune any more than necessary after midsummer or you will be cutting off buds that have started to form for the following spring.

Celeste Plunkett, Smith County Master Gardener
Texas AgriLife Extension Service


AZALEAS OF YOUR OWN

Anyone driving through Tyler this Spring could not fail to be impressed by the beauty of the azaleas in bloom.

Azaleas are very versatile, with mature plants ranging in size from one to 10 feet tall. Azaleas may be grown as pot plants, in mass plantings, as hedges, as specimens, espaliered, and in tree form.

To establish azaleas of your own, it is advisable to bare-root rootbound azaleas and plant them in a bed of prepared soil with lots of organic matter. To bare-root a rootbound, container-grown azalea, take a hose with a nozzle and wash the soil from the roots or take a knife and cut 1/2 inch down three sides of the rootball and loosen the roots.

Dig a hole in the prepared bed to accommodate the plant's newly bare roots. Set the plants on a cone of soil in the middle of the hole, and spread the roots out. Cover the roots with soil and water the plant well. Mulch the bed with about four inches of pine needles or other coarse plant fiber.

As they are getting established, azaleas should be moist at all times but never waterlogged. That's true even in the winter plants dry out even in cold weather, so be sure to keep them sufficiently damp.

Fertilize azaleas once in the spring, just after blooming, with an organic-based, acid type fertilizer, such as an azalea-camellia mix. Read directions carefully to find out how much food is needed for the size of your plants.

Pat Skarda, Smith County Master Gardener
Texas AgriLife Extension Service


LATE-BLOOMING AZALEAS

Tyler is known statewide for its beautiful Azalea Trail, with thousands of colorful shrubs lavishly painting the landscape in shades of salmon, pink, red, magenta and white. After the azalea blooms peak mid-March through early April, they fade away to be replaced by cool, green foliage that remains throughout the year.

Early April does not have to end the azalea display in your garden. There are many varieties of azaleas that bloom in April and early May, and even new varieties that re-bloom in the fall. These late blooming varieties require the same acidic, well-drained soil and partial shade as the early blooming shrubs.

Here are some of the late blooming azaleas that grow well in our area and are usually available at local nurseries:

Tall Growth Habit (6-8 feet)

  • Pride of Mobile - medium-size watermelon pink blooms
  • Judge Solomon - medium-size deep pink blooms
Medium Growth Habit (3-4 feet)
  • Glory - medium-size peach/pink blooms
  • Glacier - snow white medium-size blooms with a round growth habit
Low Growth Habit (dwarf to 2 feet)
  • Wakaebisu - medium-size salmon pink blooms on a low, spreading shrub
  • Gumpo - varieties have white or pink medium-size blooms on a shrub with spreading growth; variegated foliage is also available.

Fall is a great time to plant azaleas for color next year. Be sure and keep in mind the mature height of the plant and purchase varieties that will fit your site. That will eliminate the need to prune shrubs whose natural growth overwhelms their available space. Any pruning should be done immediately following bloom, as the buds for next year's bloom are formed in the summer.

LuAnne Ray, Smith County Master Gardener
Texas AgriLife Extension Service


PREPARING ROOTS FOR PLANTING AZALEAS

I remember years ago driving through a large subdivision in the Houston area with my father during azalea season. Most of the homes were about five years old at the time, and many, if not all, had plantings of azaleas. Dad pointed out to me that some azaleas seemed to be doing a lot better than others and asked me if I knew why. I thought it must have had something to do with fertilizer, but my father, who had landscaped a number of the homes in the neighborhood, stopped the car in front of one house and told me he wanted to show me something.

Walking up to a bed of azaleas, he lifted one straight out of the ground with relatively no resistance. He noted that this azalea had been planted several years ago, yet the root ball looked as if it had just come out of the nursery container. We then walked next door to a house that he had landscaped, and he asked me to pull an azalea out. It wouldn't budge. This little lesson soon led to my learning the importance of properly preparing azalea roots before sticking them into the ground.

As it turned out, the homeowner that had the under-achieving bed had asked for some help in getting his azaleas to look as good as the next-door neighbor's plants. We went back over the bed and easily popped out twenty or so plants. Dad took out a big screwdriver and proceeded to poke holes in the root balls and loosen the azalea roots. Next he tugged at the roots and spread them out away from the base of the plant. He explained that azalea roots like to spread out and grow fairly close to the surface to take in water and nutrients. Since the soil in this bed had been properly amended when these azaleas had originally been planted, there was nothing else to do but make an indentation in the bed shaped to receive the newly freed root system, gently backfill, and water in lightly.

That afternoon I attacked the remaining nineteen plants with the screwdriver and fondly recall driving by that house several years later and enjoying the sight of what had grown into some beautiful, large, blossoming azaleas.

Robert Leffingwell, Smith County Master Gardener
Texas AgriLife Extension Service


ENCORE AZALEAS

The Encore azalea series was developed by Robert E. Lee of Independence, LA, in the early 1980s. His intent was to hybridize azaleas that would bloom not only in the spring but also in the fall. He evaluated the color of the blossom, quality of the foliage, and vigor of the plant as well as, of course, the flowering period.

These plants flower in the spring; then they stop growing and set buds, beginning to bloom again in the summer and continuing to bloom until the weather turns cold.

Lee's original production was six cultivars. They varied in shades of pink, orange, and lavender. Some were compact in growth, and others were taller and served nicely as background plants. Now more than fourteen cultivars have been developed. They are more diverse and varied in color and size than when they were first developed.

For a list of plants and additional information, see the following website: Encore Azaleas

Linda R. Sharp, Smith County Master Gardener
Texas AgriLife Extension Service


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