Sunday, July 1, 2012

Azalea Planting Guide

Above all loves in the Louisiana landscapes is the love for the Southern Azalea.   A hardy, evergreen plant in varying sizes and endless colors, the Azalea is noted as the most popular flowering shrub in Louisiana.   A native of Japan, the close association of Azaleas and the West Feliciana Antebellum homes date back as far as 1836, and the initial planting of the Orient’s flora in Martha Barrow Turnbull’s famed `Rosedown Gardens.’
PLANTING AND BED PREPARATION:   The most important aspects in planting Azaleas are the right location and correct bed preparation.  Azaleas prefer partial sun and loose, well drained soils.  Though azaleas can tolerate full sun, they will not like wet soil conditions.  Please refer to Imahara’s Bed Preparation Guide for a detailed step-by-step description of our secrets for success in planting (also provided on website www.imaharas.com `Timely Tips’).
Remove all weeds and grasses from new bed area.  Apply weed preventative (Dimension or equal) and roto-till the earth to a depth of six to eight inches.  Raise the planting bed 4 to 6 inches minimum, amending the existing soils with aged pine bark mulch and sandy-topsoil (1: 1 ratio, one cubic yard per 160 sq.ft.). Spread peat moss (6 cu.ft. bale per 50 sq.ft. bed area) and apply fertilizer as described by manufacturer (we like `Grower’s Special’ for planting).  Roto-till to incorporate all mediums, and rake smooth, pitching slightly to encourage positive drainage.
Locate the Azaleas, dig the holes and plant the shrub.  Always plant the shrub a little above soil level remembering to allow some room to install mulch.  A two-inch layer of pine straw or pine bark mulch is ideal for the mulch material.  
The last step is to water well using a fine mist.  Remember that you have a planting medium which will absorb and hold moisture, so frequent watering won’t be necessary even in drought periods.  Watering twice a week for the first month should be sufficient to insure a proper moisture level. 
PRUNING:   Using the correct Azalea at planting with its full growth size in mind can reduce pruning efforts.   After Azaleas bloom is the ideal time for pruning.   Unless a formal clipped hedge is desired, a little shaping is all that is required.   First identify the tallest shoots, and using hand pruners (or pruning lopers for reach), cut the branches low within the shrub.   The new growth will be inside the shrub, creating a thicker, fuller shrub.   Pruning may continue through June and next year’s buds have formed.
FERTILIZING:   Azaleas need regular fertilization to perform well.  Fertilize azaleas after bloom and in combination with pruning.  Evenly broadcast (`chicken-feed’) Azalea-Camellia fertilize with a systemic insecticide evenly over the bed area, being careful not to allow fertilize to touch the base of the shrub.  It is very important to apply the systemic insecticide along with fertilize as preventative for Azalea lace-bug.   Repeat fertilization in late-Spring (June) and mid-October.  Our goal is to achieve a soil pH of around 5.5.  Don’t guess about soil pH.  Conduct a soil test.  In beds where azaleas are currently growing, use copper sulfate to lower the pH.   Foliar application of iron, such as Ironite, or a granular fertilizer containing iron may also be used to correct soil pH.
PEST CONTROL:   Azalea lace bugs are the leading pest and can be detected by the stippled white spots on the top-side of leaf.  A close inspection can reveal a small insect with `lace-like’ wings feeding on the under-side of leaf.   Infestations begin in late winter to early spring with a typical repeat in early summer, so inspect the healthy new growth regularly and treat with Triple-Action spray as required.  The best preventative is to apply a granular system insecticide when fertilizing in March, June and mid-October.
Spider mites, though not common, is currently a problem on Azaleas.  Bronzing on older leaves is one of the first indications of a possible spider mite problem.  Triple-Action spray, or a miticide, can be applied at a 7-10 day interval for control.  Usually fall, followed by late spring, is the recommended application.