Call us at 1-800-355-8086
blooming plant
of the month


(printable PDF)
If you have trouble viewing these PDF (portable document format) files, download a copy of the free Adobe Reader.

Rhododendron simsii
(ro-do-DEN-dron SIMZ-ee-ee)

Indian azalea, Sims’s azalea

Azaleas have funnel-shaped flowers in clustered heads and oblong-to-obovate-shaped, dark-green leaves. Plants are typically dwarf shrubs that grow to 1 foot to 1.5 feet tall, but topiary forms also are cultivated today.

Hues include a wide range of reds and pinks, peach, salmon, white, purple and variegated bicolors.

With proper care, azaleas in bud stage can give consumers up to six weeks of enjoyment. Azaleas in bloom provide two to four weeks of beauty. Getting azaleas to rebloom indoors can be a complicated process.

Azaleas are available year-round.

The Rhododendron genus comprises around 800 species, two of which are widely available as potted plants: R. simsii, which is, by far, the most common, and R. obtusum (Japanese azalea, Hiryu azalea, Kirishima azalea, Kurume azalea).

LIGHT Azaleas require bright, diffused light (no direct sunlight).
WATER Azaleas’ potting medium must be kept evenly moist at all times, using soft water.
TEMPERATURE Azaleas prefer cool air; 60 F to 70 F during the daytime and 50 F to 60 F at night.
HUMIDITY Azaleas like high humidity levels. Misting leaves is helpful.
FERTILIZER  No fertilization is required, unless you want to try to get azaleas to rebloom, which can be difficult; in that case, use an azalea fertilizer that contains iron.
SOIL Azaleas prefer a potting medium of equal parts peat moss and soil.
GROOMING Remove faded flowers promptly, and cut or pinch off any young green shoots that may extend beyond the blooms.

FALLING OR SHRIVELING LEAVES Leaf drop or shriveling is most often caused by dry soil. Submerge the pot in room-temperature soft water, until the potting medium is thoroughly saturated (bubbles disappear), every day for a week, and never allow it to dry out again. Other common causes are too-low humidity, too-high temperatures and too much sun exposure. If the plant has lost more than one-third of its leaves, discard it because it will never recover.
YELLOW LEAVES This is an indication of either an iron deficiency or the presence of lime in the potting medium or water. To treat an iron deficiency, fertilize the plant with an azalea food that contains iron. To rid compost of lime, treat with MultiTonic, and water the plant with soft water.
BROWN LEAVES This can be an indication of root rot caused by soil-borne fungi. Infected plants should be discarded.
PESTS Spider mites are the most common pests, and infestations occur when the air is too warm and/or too dry. Parched or crinkled leaf tips, with webbing on leaf undersides, is a sign of spider mites. Prune infested stems, but if more than one-third of the plant is infested, discard the plant.
REBLOOMING Unless you live where winters are short and mild, Rhododendron simsii plants are difficult to get to rebloom (unlike the hardy garden Rhododendrons/azaleas). Advise customers to enjoy their azalea plants as they would long-lasting flower bouquets.


fun facts


WHAT’S IN A NAME The genus name “Rhododendron” is derived from the Greek “rhodon” (rose) and “dendron” (tree).

FAMILY MATTERS Rhododendron is a member of the Ericaceae (heath) family. Relatives include Erica (heath), Calluna (heather), Gaultheria (salal/lemonleaf/wintergreen) and Vaccinium (huckleberry/blueberry/cranberry).

HOME SWEET HOME Rhododendron simsii is native to Southeast Asia and southern China. R. obtusum is native to Japan.


Some information provided by:
Botanica, by R.G. Turner Jr. and Ernie Wasson
Chain of Life Network® ,
The Complete Guide to Conservatory Plants, by Ann Bonar
The Complete Houseplant Survival Manual, by Barbara Pleasant
Hortus Third, by Liberty Hyde Bailey and Ethel Zoe Bailey
The Houseplant Encyclopedia by Ingrid Jantra and Ursula Krüger
The House Plant Expert, by Dr. D.G. Hessayon
Stearn’s Dictionary of Plant Names for Gardeners, by William T. Stearn

Super Floral Retailing • Copyright 2009
Florists' Review Enterprises, Inc.