An Azalea plant is the national flower of Nepal, and is part of an ancient group of plants dating back million of years. They are related to rhododendrons and blueberries and are descendents of Asian shrubs. Azaleas can also be used as a centerpiece for weddings or to replace expensive cut flower arrangements in your home or office. Azaleas have delicate, funnel shaped, lipped flowers that can be red, pink, white, yellow, purple and even bi-color. These plants are considered poisonous and should be kept away from pets and children. Read more about common houseplants that can be dangerous in my book Don’t Feed Me to Your Cat: A Guide to Poisonous Houseplants. Azalea plants have terminal blooms which means the entire plant flowers at one time making a beautiful display. Since florist azaleas are different than specially grown outdoor azaleas, indoor azalea plants that you receive as a gift rarely do well planted outside in your garden.
Leaves fall off an azalea plant for several reasons: The temperature is too hot or the humidity too low. The soil is too wet or the soil is too dry. The azalea plant is in a draft, near a cold door, or in front of a drafty window.
You can get an azalea to bloom again indoors but it’s not easy. Azalea plants require about 6 weeks of very cool 40°-50°F(4.4°-10°C) nighttime temperatures for their buds to set. High humidity is also necessary. Once the buds develop, move your plant to a warmer, brighter location. Indoor azalea plants may re-bloom once a year if you’re lucky.
Here are a few tips that might help the flowers on your azalea plants last a little longer. When you buy an azalea, select a plant that has only a few open flowers and mostly buds. The buds should be showing a little color. At home, place your new azalea in a bright, cool location, away from heaters, air conditioners, and direct sun. This should keep the plant in bloom for at least a few weeks.
Your azalea plant has probably gotten too dry and the soil has contracted so much that the water runs right through without being absorbed. Place the entire plant, pot and all, in a bucket or sink full of water and hold it there until the air bubbles stop coming out of the soil. Once all of the air has escaped and the soil has expanded, your azalea plant should be able to absorb water normally again.