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BOTANICAL NAME
Gardenia augusta (syn. G. jasminoides)
(gar-DEEN-yuh or gar-DEE-nee-uh,
aw-GUS-ta, jaz-min-OY-deez)

COMMON NAMES
Cape jasmine, Common Gardenia

DESCRIPTION
     Gardenia plants feature glossy dark green leaves and intensely fragrant Camellia-like waxy-petaled flowers that can grow as large as 3 inches in diameter. Bloom size and shape (flat or dome-shaped) vary among cultivars, which include dwarf and standard.

COLORS
Bloom colors range from bright white to creamy white; they change to pale yellow as they age.

DECORATIVE LIFE
Blooms can last from three to eight days, but the plants can live up to 10 years, indoors, with proper care. Unfortunately, many consumers have limited success with these plants because they are so demanding.

AVAILABILITY
Gardenia plants are available year-round from national and regional suppliers.

IN-STORE AND CONSUMER CARE

LIGHT Bright, indirect light is essential for plants displayed indoors, but protect them from direct hot midday sunlight. Outdoors (summer only), keep these plants in shady, sheltered areas.
WATER Keep the soil moderately and evenly moist—but not soggy. Water thoroughly when the soil surface is dry to the touch, using lukewarm soft water. Over watering can cause leaves to drop, and irregular and under watering can cause buds to drop.
TEMPERATURE To bloom, these plants require a consistent, narrow temperature range—62 F to 65 F at night and 70 F to 72 F during the daytime. Flower buds may drop or fail to form if daytime temperatures are higher than 75 F or if nighttime temperatures are higher than 65 F or lower than 60 F.
HUMIDITY Gardenias love high relative humidity (at least 70 percent), which is best provided with a pebble tray or humidifier. Misting the air around the plants is OK but must be done several times a day; misting leaves can cause fungal growth.
AIR CIRCULATION Fresh, moist (humid) circulating air is a necessity, especially during the winter. Hot, stale and/or dry air can cause fungal issues.
FERTILIZER  Feed the plants every two to three weeks, from April/May through September/October, with a Rhododendron (azalea) food or nonalkaline (acidic) fertilizer.
SOIL Gardenias require acidic (5.0 to 5.5 pH), moist, well-drained soil. A peat and soil mix is ideal.
GROOMING Remove blooms as they fade, and cut Gardenias back when they have finished flowering.
REPOTTING Repot plants yearly, in late winter or early spring (March-May), until the roots fill an 8-inch-diameter pot. After the root mass reaches this size, repot plants every two years.

CHALLENGES

ETHYLENE SENSITIVITY Gardenias are moderately sensitive to ethylene gas, so make sure your plants are treated with an ethylene inhibitor at the greenhouse or during transportation. Also, protect them from sources of ethylene gas, including ripening fruit, automobile exhaust and tobacco smoke.
PESTS AND DISEASES Mealybugs, scale insects, spider mites and aphids are common problems for Gardenias. An infestation can result in sooty mold or webbing on leaves. These sucking insects excrete honeydew, which supports the growth of the black fungus.
LEAF YELLOWING Causes include nighttime temperatures lower than 62 F, alkaline soil, poorly drained soil, over watering, watering with too cold and/or hard water.
BUD DROP, LEAF DROP These problems are the result of too little light, over or under watering, poorly drained soil, lack of humidity, too high or too low temperatures, and drafts.
NO BUD PRODUCTION Failure of flower buds to form is a result of too high temperatures (day and/or night) as well as too low temperatures at night.
ROOT ROT Causes include over watering and/or poorly drained soil.