This time of year, garden centers around the area are teeming with a quintessential fall favorite, the Chrysanthemum. This versatile ornamental is more commonly referred to by its abbreviated name of just “mums”.
Taxonomy and History
Chrysanthemum is actually a genus of plants which, like many others in the Aster family, has been reclassified over recent decades, adding to some additional confusion over plant names. Historical counts placed 100s of species into this genus, whereas a late 1990’s reclassification reduced that number to around 40 species. Nonetheless, the common name of mums serves a great purpose in discussing our fall classic, with nearly every garden center using the common parlance. So, I suggest asking for them by common name.
Truth be told, the garden mum varieties for sale these days are actually hybrids (Chrysanthemum x morifolum) produced through extensive crossbreeding of Asian Chrysanthemum species over hundreds of years. C. morifolum has been found to have origins associated with at least six Asian species of chrysanthemum. While it is difficult to nail down the earliest effort to hybridize mums in Asia, experts have found evidence indicating nearly 1,600 years of cultivation in China.
The mum, as we know it, did not enter our continent in cultivation until around 1800, when it was imported across the Atlantic by a New Jersey grower interested in collecting novel plants from Europe. From there, the rest is history, with mums being the second highest value floriculture crop in the US, only second to Poinsettias.
Perennial vs potted mums
With all the past breeding and history involved, it is no wonder that our modern-day mums offer so many options in color, flower shape, size, habit and other attributes. At times it can be overwhelming when selecting new mums for the garden, but there are some important basics to understand about mum care before taking home your newest selections.
While many mums are listed as perennials and it is true that varieties referred to as “hardy” mums are truly winter hardy in Zone 6, it does require consistent care to ensure they will overwinter. So, if perennial mums are your goal, it's best to plant them in the ground as early as possible in fall. Early planting allows for additional root growth before winter, setting up the most robust root system possible prior to the cold dormant season.
Container-grown mums are not well suited for perennial growth and will require extensive winter protection and other measures to ensure they come back next year. Most gardeners choose to establish perennial plantings in garden beds or very large containers, as opposed to a smaller, single-plant pot.
Soil moisture management
Mulching can greatly reduce stresses and help protect roots during wintertime. Typically, mums die in winter because their shallow, fibrous root system may get frozen as the upper soil layers freeze. In addition, the root ball of new plants can often be pushed up and out as the soil freezes and thaws, exposing the roots to the elements. Plan on adding some additional mulch to your mums either at planting time or at the end of fall as blooming begins to wane.
Mums prefer consistent soil moisture, but they cannot handle poor drainage. Be sure to plant your new mums in a location with good drainage and keep them consistently watered this fall until their foliage starts to fade.
For container mums, consistent soil moisture is also a key factor in healthy plants. Be sure pots are getting thoroughly watered, providing moisture to the full profile of the pot, top to bottom. Potted mums can also be overwatered, so take a moment to check the pot by touching the soil before indiscriminately watering. They may not need water every day if temperatures are mild. Beware that underwatering and the subsequent wilting can also resemble the effects of overwatering. The best way to ensure things are just right is checking the soil, or simply picking up the pot to judge soil moisture by the relative weight. Keep in mind that container mums will certainly not last over winter without
Sunlight requirements
Although mums are “short-day” plants, meaning they respond to shortened day length by starting to flower, it is important not to “short” them on sunlight. They truly require full sun (greater than 6 hrs. of direct sun daily) to stay bushy and full with a robust crop of blooms. Too much shade leads to few flowers, weaker stems, a thin canopy and far less root growth.
For perennial mums, too much shade over the long term adds up to make them more susceptible to winter damage as well as promoting a disappointing, straggly growth habit. With potted mums that are only expected to perform for a single fall, too much shade limits continued bud production and may take away additional weeks of blooms that a particular variety has the potential to produce. In the short term, it won’t kill the plants, but you may wind up with much more foliage than flowers.
Ryan Pankau is a University of Illinois Extension Horticulture Educator serving Champaign, Ford, Iroquois, and Vermilion Counties.
References
Ma, Y et al. 2021. Origins of cultivars of Chrysanthemum: Evidence from the chloroplast genome and nuclear LFY gene. Journal of Systematics and Evolution. 58(60), 925-944.
Qi S. et al. 2022. Natural interploidy hybridization among the key taxa involved in the origin of horticultural chrysanthemums. Journal of Systematics and Evolution. 60(6), 1281-1290.
USDA, National Agricultural Statistics Service. Floriculture Surveys. Accessed Oct. 8, 2026. https://www.nass.usda.gov/Surveys/Guide_to_NASS_Surveys/Floriculture/index.php
