Growing and Caring for Mums: A Timeless Fall Favorite

Chrysanthemums, often called mums, are a beloved autumn bloom for numerous reasons. Their striking appearance, combined with a delightful mix of sweet and spicy fragrances, creates an enchanting fall atmosphere. Available in a spectrum of vivid hues such as yellow, white, orange, burgundy, bronze, purple, and pink, mums are robust flowers that thrive in cooler climates. While they may begin flowering in late summer, they truly shine during the autumn months.

Mums are an excellent choice for enhancing your front porch decor or fall garden beds. Discover expert tips on maintaining these flowers to ensure they stay vibrant throughout the season and beyond, year after year.

Expert Insights

Essential Tips for Mum Care

Mums are hardy flowers, and with the right care, you can prolong their lifespan and even encourage certain varieties to bloom perennially instead of annually. Continue reading to learn all about their care needs.

Sunlight Requirements

"Most mums are cultivated in greenhouses due to their sensitivity to lighting conditions," explains Amber Noyes, horticulturist, ecologist, and executive editor at GardeningChores.com. "When grown outdoors, they require full sunlight, meaning an average of at least 6 hours of bright light daily."

Noyes notes that indoor mums thrive under bright, indirect light. "Mums are photoperiodic, meaning they bloom only under specific light conditions," she explains. "They typically flower in autumn when they receive 16 hours of darkness and 8 hours of daylight, which are their ideal conditions."

Soil Requirements

Outdoor mums flourish in well-drained soil, whether loam, clay, or sand-based. "For container planting, use a mix of 1:3 high-quality potting soil, 1:3 coarse sand or another draining material, and 1:3 peat moss or coco coir," advises Noyes. "The soil pH should range from slightly acidic to neutral for optimal growth."

Watering Needs

Tammy Sons, horticulturist and CEO of TN Nursery, explains that mums need frequent watering due to their exposure to direct sunlight. "Water them once daily, preferably in the evening," she advises. "This timing is crucial because morning watering doesn’t allow the soil enough time to absorb moisture before the sun evaporates it, potentially leaving the plants dehydrated."

Noyes also emphasizes ensuring water reaches 6 to 8 inches deep for ground-planted mums. For potted mums, about 1 inch of water per week is sufficient. Monitor the soil’s dryness and adjust watering as needed.

Temperature and Humidity

"Chrysanthemums thrive in USDA gardening zones 5 to 9," Noyes states. "Certain varieties, such as Mammoth Daisy, can withstand even colder climates, surviving down to USDA zone 3."

She adds that indoor or greenhouse-grown mums require a minimum temperature of 20 degrees F and a maximum of 90 to 95 degrees F. The ideal temperature range for chrysanthemums is between 62 and 72 degrees Fahrenheit.

"Mums thrive in humid conditions, ideally between 70% and 90%, which is easily maintained in a greenhouse but more challenging indoors," Noyes explains. "For home growers, aim for 40% to 50% humidity; levels below this can harm the plants. Humidity also influences their size, growth, and ultimately, their flowering."

Fertilizer Needs

Noyes highlights that mums require regular feeding, though the frequency depends on their growing environment and the type of fertilizer used. For potted mums with liquid fertilizer, apply it monthly, starting at least a month after planting and ceasing before the flower buds open.

"For slow-release fertilizers, apply every six to eight weeks, beginning a month after planting and stopping before blooming," Noyes advises. "Outdoor mums depend on soil fertility; in a well-maintained organic garden, compost at planting and possibly again a few weeks before flowering."

Sons recommends using liquid Osmocote for its gentle yet effective formula. "Apply it once a month during the growing season to achieve large, vibrant, and stunning blooms," she suggests.

Varieties of Mums

The Chrysanthemum genus comprises approximately 40 species. Below are the most favored types of mums, as recommended by experts:

• Anemone Chrysanthemum—These mums feature a raised, cushion-like center.
• Quill Chrysanthemum—These are known for their long, tubular-shaped petals.
• Spider Chrysanthemum—These have elongated petals that mimic spider legs.
• Irregular Incurve Chrysanthemum—These mums are characterized by florets curving upward toward the center, with lower petals arranged irregularly.
• Reflex Chrysanthemum—These mums display florets curving downward, with a slightly flattened bloom center.
• Regular Incurve Chrysanthemum—These mums have petals curving upward into a tight spherical shape.
• Intermediate Incurve Chrysanthemum—The petals on these mums curve loosely upward, less tightly than regular incurve varieties.
• Pompon Chrysanthemum—These mums boast globular petals that curve inward, fully covering the flower’s center.

Pruning Techniques

Noyes explains that pruning mums multiple times is essential for abundant blooms and maintaining a bushy, perennial shape.

"The initial pruning, often referred to as the first pinch, should occur around late May," she advises. "By this time, the plant should have grown about 6 inches tall, and you should trim it down to 2 to 3 inches to encourage lateral growth."

Once the new shoots reach approximately 6 inches, she recommends cutting them back again to 2 to 3 inches. "This process can be repeated until mid-July," she adds. "After that, pruning should cease as the mums will begin forming buds."

After the blooming period ends and the flowers fade, Noyes suggests a more severe pruning. Once the leaves turn yellow and start drying, cut the plant back to about 2 to 3 inches above the ground.

Propagation Methods

To propagate garden mums, spring is the ideal time. You can use seeds, cuttings, or division. Noyes notes that most gardeners prefer starting with seedlings, which should be planted in containers after the last frost, typically between May and early June.

For propagating mums from cuttings, cut stems longer than 4 inches at a 45-degree angle and remove leaves from the bottom inch of the stem. Dip the cuttings in rooting hormone and plant them in a mix of perlite and compost. Roots will develop in a few weeks, after which you can transfer them to larger pots or your garden.

Dividing mum plants is an effective propagation technique. Remove the plant from its container or dig it up, then use a sharp knife to divide the plant and roots into sections. Ensure each section has roots before replanting them in containers or your garden.

Growing From Seeds

"To grow mums from seeds, use trays filled with high-quality, well-drained, fine potting mix about six to 10 weeks before the last expected frost," Noyes recommends. "In most regions, this period falls between February and March."

She advises maintaining moist but not soggy soil at a temperature of 70 to 75 degrees F, as seedlings typically emerge within 10 to 21 days.

Once the seedlings appear, transfer them to a location with ample indirect light. Ensure the seedlings are hardened off before transplanting them into containers or your garden.

Growing in Pots

Many potted mums sold in stores are florist mums, which are less hardy than garden mums and often struggle to survive harsh winters. Check the care tag for the recommended gardening zones to determine the type of mum you have.

Garden mums flourish in zones 5-9, while florist mums are limited to zones 7-9. If you buy a garden mum, you can transfer it to a larger, well-draining pot and keep it indoors during winter for spring planting.

Keep in mind that mums thrive in sunlight, and indoor mums prefer bright, indirect light. Additionally, ensure they are watered generously, as they require ample moisture.

Overwintering Tips

While mums are cold-resistant, they still need protection from extreme cold. Apply a layer of mulch or straw around the base to help them endure winter conditions.

For potted mums, bury them in the ground and cover them with mulch, or bring them indoors to avoid freezing. This approach ensures mums survive winter and return as perennials rather than annuals.

Common Pests and Diseases

Although mums are generally hardy perennials, they can still fall victim to pests and diseases, particularly in damp conditions. Noyes highlights the following common issues:

• Chrysanthemum aphids: These pests feed on young buds and leaves. Use a garlic water spray to eliminate them without resorting to pesticides.
• Leaf miners: These larvae, from various insect species, burrow into and consume the soft tissue of mum leaves. Many gardeners control them by applying vegetable oil sprays.
• Mites: They feed on leaves but can be removed by spraying a 1:1 alcohol-water mixture and wiping the leaves with a paper towel.
• Fungal infections: Symptoms include powdery mildew and leaf rust, which can be treated by spraying a 1:10 neem oil-water mixture on both sides of the leaves and stems.
• Foliar nematodes: These leaf-dwelling parasites cause dry, dark patches and can lead to significant foliage loss if untreated. Removing damaged leaves is the first step. Some gardeners use hot water (122°F) for five minutes, though this may harm the plant and reduce blooming.

Common Issues with Mums

Here are additional common problems you may encounter with mums:

• Lanky and floppy stems, often caused by insufficient sunlight. Prune them back and relocate your chrysanthemum to a sunnier area.
• Woody stems, typically resulting from improper watering practices.
• Leaf discoloration, usually due to nutrient deficiencies, inadequate fertilization, or overwatering, unless a fungal infection is present.

When Do Mums Bloom?

Mums have extended blooming periods, usually starting in late July and continuing through October. The reduced daylight in fall triggers their blooming cycle.

Frequently Asked Questions

• Are mums pet-friendly?

  Mums are toxic to dogs, cats, and horses if ingested. According to the ASPCA, they can cause symptoms like diarrhea, vomiting, excessive drooling, skin irritation, and lack of coordination.

• What does chrysanthemum mean?

  "Chrysanthemum" derives from the Greek words khrusos (gold) and anthemon (flower), translating to golden flower.

• Do mums come back every year?

  With proper care, garden mums can return annually. Ensure they are protected during winter to enjoy their blooms each fall.