The question of whether mums survive the winter is one that occupies the minds of many gardeners as the first chill of autumn sets in. Mums, or chrysanthemums, are celebrated for their vibrant autumn blooms, but their resilience against freezing temperatures is not guaranteed and depends heavily on preparation and variety. Understanding the specific needs of your plants is the difference between a stunning perennial display the following year and a patch of dead foliage that requires replanting.
Understanding the Different Types of Mums
Before addressing survival, it is essential to distinguish between the two primary categories of chrysanthemums: garden hardy and exhibition. Garden hardy mums are bred specifically for outdoor cultivation and possess a natural resilience that allows them to thrive in colder climates. These varieties typically have smaller flowers but produce numerous buds, ensuring the plant can regenerate from the crown even if the top growth dies back. Conversely, exhibition mums are often grown in pots and displayed for short-term aesthetic impact. These varieties feature large, intricate blooms but have very little cold tolerance, making them unlikely to survive harsh winters without significant human intervention.
The Critical Role of the Crown
Why the Crown is the Lifeline
Survival through winter hinges almost entirely on the health of the crown, which is the point at the base of the plant where the roots meet the stems. Even if the top foliage is killed by frost, the crown can remain dormant and regenerate in the spring provided it is protected from prolonged freezing temperatures. A healthy crown will feel firm to the touch, whereas a rotten or mushy crown indicates rot, usually caused by excess moisture during warm autumns or poor drainage. Ensuring the crown stays viable is the primary objective of winter care, as it acts as the plant's life support system underground.
Preparing Mums for Cold Weather
Preparation begins in the late summer or early fall, well before the first expected frost. One of the most effective methods is to mulch the base of the plant heavily. Applying a layer of straw, shredded leaves, or wood chips around the base helps to insulate the soil, keeping the crown at a stable temperature that prevents freeze-thaw cycles. These cycles can heave the plant out of the ground or expose the crown to lethal temperatures. Furthermore, reducing watering frequency as the days shorten encourages the plant to harden off naturally, transitioning from active growth to dormancy.
Watering and Drainage Considerations The Balance of Moisture While it might seem logical to stop watering entirely, this is often a fatal mistake. Mums still require moisture during the dormant period, but the key lies in ensuring the soil drains exceptionally well. Waterlogged soil is the enemy of winter survival, as it promotes root rot and suffocates the roots. The ideal scenario is well-draining soil that remains slightly moist but never soggy. In regions with heavy snowfall, the natural precipitation may be sufficient, but in drier climates, a slow trickle of water once a month can prevent the roots from desiccating completely. Pruning Strategies for Winter
The Balance of Moisture
While it might seem logical to stop watering entirely, this is often a fatal mistake. Mums still require moisture during the dormant period, but the key lies in ensuring the soil drains exceptionally well. Waterlogged soil is the enemy of winter survival, as it promotes root rot and suffocates the roots. The ideal scenario is well-draining soil that remains slightly moist but never soggy. In regions with heavy snowfall, the natural precipitation may be sufficient, but in drier climates, a slow trickle of water once a month can prevent the roots from desiccating completely.
Do not rush to prune your mums in the fall. Leaving the dead foliage standing throughout the winter provides a protective barrier against cold winds and snow. This top growth traps insulating air around the crown, keeping it warmer than the ambient air temperature. It is best to wait until early spring, once the threat of hard frost has passed and new growth begins to emerge from the soil. At this point, you can cut back the old stems to about four to six inches to encourage fresh, vigorous growth for the upcoming season.
