Learning how to grow chrysanthemums—or mums, for short—indoors makes it possible to harvest their blooms for cut-flower displays or floral arrangements. Leave the plants intact to enjoy their beauty. Growing them indoors might even help remove air pollutants. NASA scientists included mums in a two-year study as representatives of flowering plants. You will be in plentiful company: chrysanthemums are so popular with Americans that the National Chrysanthemums Society reports them to be the most commonly grown potted plant in the nation.
Choose your propagation method. You can grow indoor chrysanthemums from seeds or rooted as well as unrooted cuttings of florist mums. Hybridization created these plants to be spectacular in color and shape but they lack the hardiness required to survive winter outdoors. If you already have a number of mums you need to divide, simply use the rooted cuttings from those plants to get started. Opt for seeds or unrooted cuttings if you are growing your first chrysanthemums.
Fill your pots with soil and plant your mums. Choose soil that is coarse and provides good drainage. Keep the soil pH between 5.7 and 6.2. If you grow your indoor chrysanthemums from unrooted cuttings, stick them into the well-watered soil to a depth of about 1/2 to 1 inch. Remove the bottom leaves if they touch the soil. Place rooted cuttings into the soil sufficiently deep to keep the plant in place. Because mums have shallow roots, make sure not to plant the cutting too deep. Place seeds on top of the watered soil and cover them with a thin layer of dirt. Mist the top soil.
Water and fertilize your indoor mums consistently. Do not let the soil dry out completely in between waterings. Saturate the soil but drain the saucer underneath the flowerpot after the water has had a chance to drain. If you notice yellowing leaves, you might be overwatering your plant. Cut back a little on your watering schedule and allow the top of the soil to dry before resuming. Nourish mums prior to blooming every other week with water-soluble fertilizer.
Use your thermometer to maintain optimum indoor temperatures. Chrysanthemums thrive in mild temperatures. Do not let the night temperatures go lower than 60 degrees Fahrenheit. Daytime temperatures around 70 degrees F are optimal for blooming plants. If you notice black spots on some leaves or fungal growth on lower ones, the plant might be getting too cold. Make sure it is not in the direct line of an air-conditioning vent or other source of cold air.