Gardenias were discovered in China in the 1700’s. Their fragrance is unmatched in the floral world, and the extracted oil from the flowers is used in making perfume and tea. They are not hard to grow if you meet the plant’s basic requirements for good health.
Light – Gardenias need at least four hours of sunlight a day. During the hot summer months, a light curtain filters out some of the intensity and protects foliage.
Water – Gardenias do not like to dry out. (Soil may dry over the top between thorough waterings.) Keep the soil moist but not sodden. They should never be allowed to stand in water. During the winter, the plant may use less water due to reduced light levels. Cut back on the watering, and let the top 1/2” of soil go dry before watering.
Humidity – Gardenias do enjoy humidity. If the winter air in your home is dry, especially if you heat with forced hot air or woodstove, try growing your plant on a pebble tray. Get a large, plastic plant saucer. Put a layer of gravel in it about 3/4” deep. Pour water into the stones, but do not let the water reach the top of the gravel where the plant roots could come in contact with it. Place the pot on the wet stones. As the water evaporates, it forms a little pocket of humidity that the plant can enjoy.
Temperatures – This is a crucial point if you want your plant to bloom. During the day, temperatures that are comfortable to humans are fine for gardenias. At night, temperatures should drop to 50-55 degrees, no more than 63 degrees. The flower buds will drop off if temperatures are higher.
Fertilizer – Gardenias need an acid-based fertilizer to keep the soil at the proper pH. It is important to use an acid based plant food. Fertilize monthly. Cut back on feeding in the winter months.
Repotting – Use a peat-based potting soil to which no lime has been added. Gardenias do not need to be transplanted frequently, only when their roots have almost filled their pots. Soil should be well drained.
Bud Drop – Usually caused by plant stress – not enough water, humidity too low, and temperatures too high. Problem is usually self-correcting if above plant needs are met.