Plant Care

  • Plant Care Guide


Largest Wholesale Growers of Specimen Azaleas In the Southland





PLANTING … Azaleas are shallow-rooted and should be planted in a well-drained acid soil mix.  We recommend 40% peat moss, 40% pine bark and 20% good, light soil, or sponge rock if the soil is clay or hard.  Dig hole at least three times as wide and a few inches deeper than size of container.  Place plant about 1 inch above ground level so that the roots may obtain air, fill peat mix around ball of plant firmly, water thoroughly, and make certain good drainage is maintained.


WATERING… Surprisingly, the word “azalea” comes from the Greek work meaning “dry”.  Actually, more azaleas die from over-watering than from all other causes.  They should be kept moist, but never soggy wet.  Water well and deeply, but only as often as your own weather conditions demand.


FERTILIZING… Azaleas are very light feeders; and three to four feedings spaced from April through September are sufficient.  Use a good azalea acid food.  Azalea leaves are sometimes subject to chlorosis, a yellowing between veins.  This is usually caused by a lack of iron, and will most often respond to an application or two of chelated iron.


PRUNING…Heavy pruning of undesirable branches should be done when they are at their peak of bloom (use the branches as cut flowers!)  Most varieties of azaleas require one good pinching or pruning of new spring growth in July, thus creating more branches and bushiness for fall bud setting.  However, when plants are young and vigorous, especially with the Southern Indicas, pruning on new growth should continue through September.


PEST CONTROL… Azaleas are comparatively free of insects and disease, but for good healthy, pest free plants, a precautionary spraying in late spring (after blooming) and fall can reduce the damage of thrips and mites.


AZALEAS IN THE LANDSCAPE… No other flowering shrub has contributed more to the American garden than the azalea when one considers that, by proper selection of varieties, color can be had from October through June.  Azaleas can be used in mass plantings or spotlighted as single specimens. They can be shaped as bushes, hedges or trees.  They thrive in hanging baskets and decorative pots, and some varieties are very popular for bonsai.  The versatility of this plant is unlimited.  However, most azaleas are at their best when planted in groups or drifts.  An ideal situation for them would be among high trees so spaced as to allow the sun and light to penetrate yet providing intervals of shade to give the plants some respite from the hot sun.  Where there are not trees, the north or east side of the house or high fence would be desirable.  Many azaleas do thrive in full sun, notably the Southern Indicas.

Site Preparation If an azalea were growing in ideal conditions, the

area around it would have a generous share of organic matter, and would be acid.  The soil would retain a moderate amount of water, but would be well drained so that excess water would never stand around the roots.  The soil would be somewhat crumbly, with plenty of ores for air to penetrate the root area.  There would be a canopy of leaves above the plant provided by pine or hardwood trees to filter the light and protect the plant from harsh winter conditions.  The soil would be adequately fertile to insure vigorous growth.

If any of these conditions do not exist where you wish to plant your azaleas, you must modify your soil.  First, make sure that your planting site is not on a windy hilltop or in a low bottom area which is a frost pocket.  If your soil is excessively sandy and has a low organic content, you should add organic matter in the form of peat moss, pine bark mulch, leaf mold, compost, well-rotted sawdust, rice or peanut hulls, etc.  A soil test is invaluable in determining the organic matter content and many other soil features.  Do not amend the soil with hardwood bark or fresh sawdust.  Till in the organic amendment to a depth of 4”-6”.

Ask your extension agent to help your interpret the soil test, and recommend the proper amount of fertilizer to add to the soil.  Often little or none is needed, but you might need a modest amount of balanced fertilizer or super phosphate.  If the soil has a high clay content, you might need an amendment to help loosen the soil in addition to the organic amendment.  Coarse builder’s sand or gypsum might fill the bill.  Clayey soils must be amended so that they will allow root penetration and drain properly.

The pH is especially important for azaleas, since they thrive best in acid soil.  The ideal pH is 5.0-5.5.  If your soil is more acid than this (below 5.0), incorporate dolomitic lime into the soil.  If the soil has a pH above 6.5, add sulfur or ferrous sulfate.  Once the pH, organic matter content, drainage, and fertilization have been attended to, you are ready to plant.

Planting Azaleas  As the old saying goes, don’t dig a $5.00 hole for a $10.00 plant.  Dig your hole twice as large as the root ball.  It should be 4”-6” deeper than the height of the root ball.  Take the soil which has come out of the hole and mix it 50-50 with a good organic amendment.  Those mentioned above are all good, especially peat moss.  If the ground is dry, water the hole thoroughly.  Watch to be sure that the whole drains in a reasonable period of time. The spacing of your plants will depend on several factors.  Do you want a planting in which the plants merge, are you preparing a hedge, or do you want individual plants?  Generally for plants which will grow side-by-side, spacing should be 2’ – 3’ for low and dwarf plants, and 4’-6’ for large growing azaleas.  Check the varietal growth habits for your varieties.

When selecting azaleas it is best to deal with a reputable nurseryman.  He will usually have the best selection, and will be able to give you first-hand advice.  Select only plants which look healthy, and have signs of recent growth recent growth.  Do not purchase plants which have dead stems, yellow leaves, or long leggy shoots.  The head of the plant should not greatly exceed the pot size, and the roots inside the pot should not be tightly pot bound.

Gently take the root ball out of the container, and place the plant into the hole.  Remember that the azalea is a shallow rooted plant with a lateral root system. This is because azalea roots must be near the surface of the soil in order to aerate freely.  So, the top of the root ball must be slightly above, the level of the soil.  Firm the bottom of the hole to be sure that the plant does not sink, and then backfill with the enriched soil.  Ideally, the azalea should be just slightly up out of the ground, perhaps 1” above ground level, when finished.  Gently tamp, but do not pack tightly, the soil around the plant, leaving the plant standing upright.  Water thoroughly; allow draining a few minutes, and watering again.

Azaleas can be planted almost any time of year, even when they are in full bloom.  The best times for planting are late fall, early winter, or early spring.  Remember that if a plant is to grow vigorously during the next warm season, it must have a mature root system to give it water and nutrients.  Azaleas need to be planted at least 6 – 8 weeks prior to the arrival of warm weather in order to produce a good set of new feeder roots.  Azaleas planted while in bloom in the springtime will not be as established, or grow as well, as those which have been placed in the ground during the previous fall or winter.

Mulching Azaleas  One of the most important parts of the planting process is mulching.  By covering the area above you will greatly enhance the chances of that plant to survive and grow vigorously.  A good mulch should be heavy enough not to blow away and loose enough to allow movement of air to the root zone.  It should be organic in order to add humus to the soil and to keep the soil acid.  Good mulches which accomplish this include pine needles, pine bark, leaf mold, and peanut hulls.  Peat moss, fresh sawdust and freshly dropped leaves are not recommended.

During the warm months mulching is quite important.  It helps to conserve water during stressful drought periods.  Mulch also helps to keep the root zone cool during hot periods.  It reduces the weed population as well.  During the cold seasons of the year a good mulch will insulate the roots and protect them from the freezing elements.  It will also absorb water, and help the root ball to retain water at a time when dry freezing can be especially harmful.

Often times plants are lost in winter when they freeze and the bark splits just above the ground level.  A good layer of mulch three inches to four inches thick around the main trunk of the plant can help prevent this.  A rich dark layer of mulch under a plant will make it appear neater and improve the appearance of the entire area.

Mulching should be done whenever the plant is installed.  You should then check each fall and spring to see if the mulch needs to be replenished.  If so, rebuild the layer to the original depth.  Since azaleas are sometimes planted slightly up and out of the ground, a good mulch can be used to cover the top of the root ball and the exposed edges.