Plant Particulars November 2012

Each autumn chrysanthemums (Chrysanthemum sp.) dominate our landscapes and stores alike. Native to China and Japan, mums are revered as national symbols. Chrysanthemums come in dozens of flower forms in shades of yellow, pink, red, white, bronze, and lavender. Flower forms include cushion, decorative, pompon, quill, single (daisy), spider, anemone, and spoon just to name a few!

Each fall these beautiful flowers appear in stores and many wonder how they can grow them at home. Mums can be divided into two major categories: garden (or hardy) and florist (or exhibition) types. The latter are not winter hardy and should be enjoyed indoors or as an annual outdoors for the season and then composted. When inside keep the soil moist, but not wet, and in a cool location out of direct sun to keep the blooms vibrant the longest.

The garden or hardy type mums are sometimes successful in Iowa gardens, but many labeled as “hardy” are not. Most will survive to USDA Hardiness Zone 5. If you wish to grow your mum as a perennial, plant them in the spring. Fall-planted plants often do not have enough time to establish before winter. Their shallow root system allows them to easily heave out of the soil during the freeze-thaw cycles that happen during the winter which will kill the plant. To help prevent heaving, leave stems and leaves on the plant until spring and cover crowns with a layer of mulch. Mums like fertilizer and should be fertilized once a month until July. Plants do best in fall sun, although they will tolerate light shade and require well-drained, but not dry soil. To encourage bushiness and more abundant blooms, pinch plants two or three times before August 1 by removing the top inch or two of each stem. This reduces the height of the plant and encourages branching and more flowers. A good rule of thumb is to pinch on Memorial Day and the Fourth of July. If you pinch any later than August 1 you run the risk of removing flower buds. Flowers tolerate light frost well and will be colorful from September until a killing frost.

Every fall Reiman Gardens features hundreds of beautiful fall mums in the outdoor containers and Conservatory.

Prepared by Aaron Steil, Education Coordinator