Chrysanthemums are among the most popular perennial flowers in the world and are the showiest of the fall perennials.
These flowers have been cultivated for centuries around the world. They are available in almost every color except blue and are widely available in local garden centers.
Carrie Christenson, a garden supervisor at Thanksgiving Point, has just finished helping to plant thousands of mums as part of the Mum Festival in the facility's Italian water garden.
She said the mum's popularity stems from the fact that they are "low maintenance plants" and that "when other plants are slowing down, they are in all their glory."
Chrysanthemums grow well in any good garden soil, but they do need well-drained soil because they have shallow root system. Plants in poorly drained soils develop root diseases and winter kill.
"If you are planting blooming plants, be certain that you water them in well," Christenson said. "They do not need as much water as annuals. Although the temperatures are cooling down, newly transplanted mums have a small root system compared to the size of the plant."
"Sometimes the plants are root bound inside the pots, so you might have to cut the root ball so they will root in well. This is particularly important if you are going to leave the plants in so they can bloom next season."
Mums were first cultivated as flowering herbs in China in the 15th century B.C., where the plants were believed to have the power of life. Japan imported mums in the eighth century A.D. where they became so popular their likeness was adopted into the Emperor's crest and official seal.
Mums made it to the Western world in the 17th century. In 1753, Swedish botanist Karl Linnaeus coined the term "chrysanthemums" by combining the Greek words "chrysos" — meaning "gold" — and "anthemon" — meaning "flower."
Mums came to the United States during colonial times. Today, they're the undisputed "Queen of the Fall Flowers."
During the summer, when days are long and nights are short, chrysanthemums grow vegetatively. As the nights grow longer in early fall, mums initiate flower-bud formation.
There are three types of mums and you can choose for your landscape: Cut flower mums, pot mums and garden mums.
Cut flower mums produce large flowers with long, strong stems. Pot mums are beautiful container plants that feature large flowers. Cut flower and pot mums are produced year-round. Greenhouses artificially shorten or lengthen the night by covering the plants with black cloth or giving them artificial light to induce them to bloom out of season.
Cut flower and pot mums are not suitable for gardens because they get tall and leggy.
For the garden, Christenson recommends short, stocky plants that hold in a tight clump and do not pull apart. The best garden mums grow 12-18 inches tall and cover themselves with clusters of small 1-inch to 1 1/2-inch flowers.
Mums grow best when they receive full sun. Plants in shade grow taller, have weaker stems, smaller flowers and bloom later in the fall. Avoid planting them where they compete with trees for light and water.
Some gardeners use mums as temporary landscape color. When the flowers fade, they remove the plants and replace them with cool-season bedding plants.
When purchasing garden mums, select plants that are just starting to bloom. Fully open plants will not be attractive as long. Let the flowers remain until they finish blooming or the weather gets so cold they freeze. Then cut the dead foliage down to about two inches high.
By planting adapted varieties, chrysanthemums make an excellent perennial to beautify the fall garden for many years.
Larry A. Sagers is the regional horticulturist, Utah State University Extension at Thanksgiving Point.