Chrysanthemums, commonly known as mums, are a signature plant of the fall season, offering a burst of color when many other flowers fade. Mums are often purchased in full bloom in a pot for seasonal outdoor display. Keeping a potted mum vibrant and healthy requires focused attention on its environment, water needs, and ongoing maintenance. This guidance will help extend the life of your potted chrysanthemum beyond a simple seasonal arrangement.
Optimal Outdoor Placement and Environment
Mums thrive in a location that provides ample sunlight to support their extensive flowering. A potted chrysanthemum should receive a minimum of six hours of direct sunlight each day to maintain dense foliage and prolific blooming. Placing the pot in a spot with a southern or southeastern exposure is often ideal for achieving the necessary light intensity.
Proper air circulation is also important for the health of the plant, helping to prevent the development of fungal diseases like powdery mildew. Position your mum away from sheltered corners where air becomes stagnant, but also protect it from harsh, strong winds that can damage the blooms and dry out the soil quickly. Additionally, be aware that artificial light from street lamps or porch lights can interfere with the plant’s natural light-response flowering cycle, potentially inhibiting bloom production.
Potted mums must be kept in containers with adequate drainage holes to prevent waterlogging. Chrysanthemums are highly susceptible to root rot if they sit in overly saturated soil. Avoid placing the pot directly on a solid surface that might block the drainage holes, causing water to collect at the base of the roots.
Watering and Moisture Management
Potted mums are thirsty plants, and maintaining consistent soil moisture is important for their care. The soil should be kept evenly moist but never soggy, as the confined space of a pot causes the soil to dry out faster than in-ground plantings. Check the soil daily, providing water when the top inch of the soil feels dry to the touch.
When watering, soak the soil deeply until you see water flowing freely out of the drainage holes at the bottom of the pot. This deep watering ensures that the entire root ball is saturated, which is particularly important as the plant is actively flowering. To minimize the risk of foliar diseases, aim the water directly at the soil line and avoid splashing the leaves and blooms.
Potted mums purchased in full bloom generally do not require immediate fertilization, as growers typically provide nutrients for the current bloom cycle. If you plan to keep the plant for an extended period, apply a light, balanced liquid fertilizer every two to three weeks until buds show color. Applying fertilizer in the fall is not recommended, as it encourages new, tender growth when the plant should be focusing on flowering and preparing for dormancy.
Essential Maintenance for Prolonged Blooms
To encourage the longest bloom time and maintain a tidy appearance, consistent deadheading is necessary. Deadheading involves removing spent or faded flowers, which stops the plant from diverting energy toward seed production. This redirection encourages the plant to produce new blooms and buds, effectively extending the color display.
Use clean snips or sharp scissors to remove the spent flower head, cutting the stem just above the first set of healthy leaves below the faded bloom. For the best visual result, make the cut deep enough that the remaining stem is hidden within the surrounding foliage. Regular deadheading, ideally done once a week, also improves air circulation, preventing fungal issues.
Regularly inspect the foliage for common pests, such as aphids or spider mites. Early detection is key; a gentle spray with insecticidal soap or neem oil can manage minor infestations before they spread. Removing any yellowed or damaged leaves while deadheading also contributes to the plant’s overall health.
Preparing Mums for the Dormant Season
Once the blooms have completely faded and the foliage begins to turn brown after a few hard frosts, the plant is ready for its dormant phase. At this point, the stems should be cut back to a height of about three to five inches above the soil line. This step removes the dead top growth and helps the plant conserve energy for the next growing season.
If you have a hardy garden mum variety, the best chance for survival is to transplant it from the pot directly into the ground. Planting it as soon as possible allows the root system time to establish before the ground freezes solid. If the mum is a less hardy florist variety or if you live in a colder climate (generally USDA Zone 4 or below), the potted plant must be overwintered in a protected location.
Move the pot to a cool, dark, or semi-lit area, such as an unheated garage, shed, or cold frame, where the temperature remains between 32 and 50 degrees Fahrenheit. The goal is to keep the plant dormant but prevent the roots from freezing solid. Throughout the winter, water the pot minimally, just enough to keep the soil from completely drying out, as overly dry roots are a common cause of failure for overwintered potted mums.