Chrysanthemums are one of my favorite perennials

Sharon Lance
Adams County Master Gardener

This genus of about 30 species in the Asteracea family is native to Asia and northeastern Europe and the flower of this herbaceous perennial (a plant that forms a soft, tender rather than woody stem) comes in many forms and colors. When you are ready to purchase or plant mums determine the location for the plant keeping in mind that they are shallow-rooted plants and should not be planted in a location where the mum is in competition with the roots of other plants or trees. Other considerations are the height and the width of the mum. Look for compact bushy plants, because they will flower better than larger specimens Next, examine the leaves, which should be green in color, not mottled with yellow, ragged or dead edges, which can be signs of a diseased or distressed plant. Most plants, including mums, come with a plastic stake that provides information about the plantsí color; height, width and can include planting instructions.

Mums are easy to propagate and spring is a good time to do this by plant division, or cuttings. Plant division can be done after the plant has grown to at least 3" in height. Just dig up the mum and slowly pull apart selecting sturdy stems with sufficient roots. Plant in fertile, well-drained amended soil in a sunny location Space your mums 18-24 inches apart. Because they have a shallow root system, mulch them to keep roots cool and conserve ground moisture. Cut or pinch off approximately three-quarters of an inch from the top of the new plant so that the plant can use its energy to develop the root system instead of flower development. This is an easy way to share your new plants as well as multiplying the plants in your perennial garden. Another pay to propagate chrysanthemums is to place cuttings that have had the ends of their stems dipped in root hormone (tap off excess powder) place in damp sand away from the sun. Allow several weeks for the roots to develop before checking the root development. Once the plant has developed a sufficient root system move it into a 4-6" pot using a soilless mix. I have been successful by taking plant cuttings, and planting them directly in the ground. I start by making the width of the hole at least 3 times the width of the stem by using a pencil or similar implement. Next, partially fill hole with potting soil, remove side-shoots from the cutting before dipping in root hormone (tap of excess powder), and fill hole with potting soil. Lightly press the soil around the stem of the plant, water and mulch.

You need to find the method of propagation that works best for you. If you are propagating more than one plant, consider using some method of marking the planted area or container with the color/height of the plant. I have used popsicle sticks as well as wood sticks that can be purchased at a craft store.

In the summer continue to pinch back the plants tips to keep the mum trimmed to a height of 6-8" and again before the end of August so the plant has time to set new flower buds. Another reason to pinch back is to encourage the plant to develop side shouts, which will send out more blooms instead of the plant being tall, and having stragley stems. During the summer you may need to water more frequently to keep the plant from drying out. Continue to fertilize every couple of weeks.

Fall climate is perfect for mums because chrysanthemums are sensitive to day length (night length). They are short-day (long-night) plants. Scientists discovered it is not the length of the light period, but length of uninterrupted dark periods that are critical for flower development. During the fall period when the days grow shorter you will see increased growth in stem and leaf as well as bloom development on the Chrysanthemum. Also, temperature affects a plantís productivity and growth; Mums flower for a longer period of time if daylight temperatures are around 59 degrees. In the fall, after the frost has destroyed the blooms trim/cut back the plant 2-3 inches from the ground and mulch heavily to protect the roots for the upcoming winter.

Summary: In the fall when many other perennials start to fade I can look forward to the long lasting blooms of the chrysanthemums, and so can you. Keep in mind, regardless of the season you plant your mum, that they require full or partial sun. They are shallow-rooted plants that will benefit from planting in soil that is rich in compost or organic matter, which is derived from decomposed plants, such as grass clippings, leaves or twigs and should be heavily mulched to retain moisture. Also, do not plant mums where they will be in competition with another plantsí root system. Unless mums are stressed by unfavorable growing conditions they are relatively pest free. They can be propagated from late spring to early fall by a method that works best for you. Chrysanthemums require bi-weekly fertilization from late spring to the end of August and hand trimmed or cut back during the same period to ensure this day length flower will bloom in the fall. It is critical to mulch over winter to keep the roots from drying out. In the fall of the year after my mums have bloomed I take a few minutes to draw out the areas where I have my mums planted. I note the colors in my diagram. Then, the following spring, when I am ready to move or propagate my mums, I have a reference to the color and characteristics of all my flowers. Share your mums with your friends. Remember "mum" is the word!

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