Gardenia - A tropical treat
The gardenia is best suited for the experienced gardener, since it requires considerable maintenance. Fall or spring is the best time for planting. Gardenia prefers light to moderate shade and should not be planted close to other plants or trees. They like their own space and their root structure does not like interference from other roots. Gardenia also grows very well in pots. Since the gardenia is native to China where the climate is warm, I would recommend starting gardenia in a pot and allow it to be outside as the weather permits then bring it in your home during winter. This will put less stress on the plant if you will be transplanting it into a pot to bring in the house if the weather gets too cold.
Gardenia is an evergreen shrub that grown two to six foot high, depending on the variety. It will spread out about the same. The foliage on gardenias is glossy, dark green are about two to four inches long and half as wide. The flower can be single or double and up to four inches in diameter. They are waxy, white and very fragrant which has made the gardenia a favorite scent for perfumes and body lotions.
Gardenias prefer acid, moist, and well drained soils. So use fertilizer and plenty of organic matter, such as compost or ground bark, to as large an area as possible. Mulch plants instead of cultivating. A good time to feed gardenias is March, using an acid plant food, fish emulsion or blood meal. Feed the shrubs again in late June to encourage extra flowers or faster growth of young shrubs. Do not fertilize gardenias in the fall since it will stimulate tender growth, which may be killed if the temperature in winter drops below 15 degrees. Gardenias are cold sensitive. During severe winters they can be killed but will often regenerate in spring.
Prune shrubs after they have finished flowering to remove straggly branches and faded flowers. Water gardenias regularly but make sure you keep water off the foliage and blossoms. This will prevent leaf mold. Regular watering will keep the plants in good condition so they can withstand winter weather if you choose to let them over winter.
Several insects and diseases are prone to show up on your gardenia. When a sooty mold coats gardenia leaves in summer, it is usually due to an infestation of whiteflies. These insects look like little bits of cotton. While eating, they excrete excess moisture in the form of honeydew and this encourages the growth of a black fungus. Small gray aphids, which cling to leaf undersides, have a similar habit.
Nematodes are microscopic worms, which live in the soil and feed on plant roots. They live in sandy soils and can cause gardenias to be stunted or even die. Root rot caused by fungi can also be a problem in poorly drained soils.