Gardening Plants & Flowers Flowers

How to Grow Hardy Mums for Blooms Year After Year

Keep Mums Flowering With Easy Care Tips

Hardy mums are herbaceous perennial fall flowers with characteristic daisy-shaped flowers. Mums are perennials in moderate climates and treated as annuals planted as fall flowers in northern regions to provide vivid color. They grow best in full sun, well-drained, slightly acidic soil, and average humidity levels.

Hardy mum plants with red, orange and purple flowers in garden

The Spruce / Gyscha Rendy

Hardy mums are fast-growing and will reach their full height within their first year, with the plant filling out a little more each subsequent year. Hardy mums set buds once the nights become longer and flower in the fall for up to eight weeks. The leaves and flowers of hardy mums are mildly toxic to humans as well as to dogs, cats, and horses.

Common Name Hardy mum, garden mum, florist's daisy
Botanical Name Chrysanthemum morifolium
Family Asteraceae
Plant Type Herbaceous, perennial, annuals
Mature Size 1–3 ft. tall, 1–2 ft. wide
Sun Exposure Full
Soil Type Moist, well-drained
Soil pH Acidi, neutral
Bloom Time Summer, fall
Flower Colors Yellow, red, pink, purple, orange, white
Hardiness Zones 4–9 (USDA)
Native Area Asia
Toxicity Mildly toxic to people and animals

Hardy Mum Care

Here are the main care requirements to keep mums healthy.

  • Plant mums in a site that’s protected from damaging strong winds.
  • Provide good air circulation around the plants to reduce fungal infections.
  • Pinch plants on or around Memorial Day and Fourth of July for best fall performance.
  • Water weekly and feed regularly.
Hardy mum plant with red flowers and leaves closeup

The Spruce / Gyscha Rendy

Hardy mum plant with bright red flowers and leaves

The Spruce / Gyscha Rendy

Hardy mum plant with light pink flower closeup

The Spruce / Gyscha Rendy

Light

Hardy mums prefer to grow in full sun, meaning at least six to eight hours of direct sunlight daily. However, in the warmer parts of their growing zones, they can benefit from some afternoon shade. The flowers are photoperiodic, meaning they bloom in response to the shorter days and longer nights experienced (in the northern hemisphere) in the late summer and fall. Therefore, don't plant them near street lights or night lights; artificial lighting wreaks havoc with their flowering cycle.

Soil

These plants grow best in organically rich soil with a slightly acidic to neutral soil pH (6.2 to 7.0). Sharp drainage is a must, as soil that remains wet for too long can cause root rot.

Water

Mums like consistent moisture but they do not tolerate soggy soil. Water whenever the soil dries out about 1 or 2 inches down. In warmer weather and once the plant is large and in bloom, more frequent waterings will likely be necessary. About 1 inch of water per week is considered a minimum.

Temperature and Humidity

Most garden mums can handle temperatures up to 100 degrees Fahrenheit with sufficient water and some shade. Most hardy mums continue blooming as temperatures dip down as low as 20 degrees Fahrenheit and the roots of most varieties can survive winter soil temperatures down to less than zero degrees Fahrenheit. However, it's best to choose varieties bred to thrive in your region's particular conditions.

A moderate humidity level is ideal for these plants. Excessive humidity can encourage fungal diseases, such as leaf spot.

Fertilizer

Mums are fairly heavy feeders. You can use a slow-release fertilizer in the spring, following label instructions. Or use a water-soluble fertilizer monthly through July. Any fertilization after July can trigger tender new growth that cold fall temperatures maydamage. 

Types of Hardy Mums

Mums are recognized for their particular characteristics and there are many named varieties. The most popular categories include:

Anemone

This group features long, flat petals on blooms that reach a maximum size of around 4 inches. Varieties include the following:

  • 'Dorothy Mechen': Light purple blooms
  • 'Adrienne Mechen': Flowers with a pink center that fades to bright white tips
  • 'Samba': Rose-pink flowers
  • 'Rhumba': Coral red flowers
  • 'Harmony': Bright yellow blooms
  • 'Overture': Bright red flowers
  • 'Ruby Mound': Semi-double bright ruby-red flowers

Pompom

Pompom (also spelled pompon) mums are fluffy flowers that are also known as button mums. All varieties produce compact blooms in various colors. Some common varieties include:

  • 'Patriot': All white flowers
  • 'Garnet': Crimson blooms that mature with bronze overtones
  • 'Barbara': Small, purple flowers

Spoon

Named for its spoon-shaped petals, this type of mum grows petite flowers up to 4 inches in diameter. Popular varieties include:

  • 'Kimie': Yellow-gold petals
  • 'Matchsticks': Yellow centers that end dramatically in bright red "spoons," and
  • 'Yellow Quill': Bright yellow centers that fade into creamy white tips

Newer Varieties for Northern Climates

Historically, garden mums are regarded as hardy only to USDA zone 5, but there are recent introductions by Canadian and University of Minnesota horticulturalists who have created many varieties hardy to zone 4, and some even to zone 3. If you live in a northern climate, consider one of these:

  • My Favorite series: developed by the University of Minnesota, this mum is hardy into zone 3b. Plants are up to 4 feet tall, with coral, pink, or yellow flowers.
  • Morden series: Developed in Canada, these jewel-toned mums should be reliably hardy into zone 3. Named cultivars include 'Morden Canary', 'Morden Delight', 'Morden Fiesta', and 'Morden Garnet'.

Other cultivars zone 3 and 4 gardeners can consider include those developed by the University of Minnesota:

  • 'Peach Centerpiece': Peach-hued flowers
  • 'Rose Blush': Delicate, double, rose-colored blooms
  • 'Sesquicentennial Sun': Double-gold blooms
  • 'Betty Lou Maximum': Large red flowers

Propagating Hardy Mums

Hardy mums can be propagated in many ways, but the easiest is by dividing the root clumps in early spring.

Propagating via Division

  1. In spring just as new growth is starting to appear, use a shovel to carefully dig up the entire plant, including the crown and the full root clump.
  2. Use a sharp knife to cut the clump into sections. Each section should include a healthy group of roots attached to a portion of the crown.
  3. Immediately replant the divisions into the desired locations. If planting in groups, space the pieces at least 1 foot apart.

Propagating via Stem Cuttings

  1. In late spring or early summer when the initial shoots are 6 to 12 inches long, use sharp pruners to cut off 3- to 4-inch stem tips.
  2. Pinch off the lower leaves, then dip the bottoms of the cuttings in rooting hormone.
  3. Plant the cuttings in a rooting medium, such as coarse sand or perlite.
  4. Keep the cutting moist until roots begin to develop—generally four to five weeks.
  5. When a good network of roots has developed and the cutting is showing new leaf growth, carefully transplant the cuttings into the garden or pots filled with standard potting mix.

How to Grow Hardy Mums From Seed

Growing hardy mums from seed is no easy task. The seeds are tiny and it takes as much as 16 weeks for germinated seeds to develop into mature flowering plants. Collecting seeds from existing plants is an unreliable method of propagation because mums cross-pollinate freely and the plants produced from collected seeds might not be similar to the parent plants.

But if you want to propagate mums from seed, collect some of the dust-fine seeds from dried heads of spent flowers. Buy packaged seeds from a supplier for better results. Start seeds indoors at least six weeks before the last expected frost date.

  1. Fill a seed tray with a fine seed-starting medium, and dampen it slightly.
  2. Carefully sprinkle seeds over the tray by pinching them between your finger and thumb and rubbing them together over the tray.
  3. Just barely cover the seed with seed-starter mix, lightly mist the surface with water, and tamp the soil lightly to ensure the seeds are in contact with the mix.
  4. Place the tray in a very bright, warm (70 degrees Fahrenheit) location, and keep the soil lightly moist. In 10 to 15 days, germination should occur.
  5. Thin out the seedlings as they grow, but don't attempt to transplant them into individual containers or the garden until they are at least 3 to 4 inches tall.

Potting and Repotting

Grow hardy mums in containers by planting them in a well-draining pot with peat-based potting mix. If you live in a climate where garden mums are hardy, you might be able to overwinter the potted plant by moving it to a cold frame or other sheltered location. Otherwise, potted mums can be grown as annuals and discarded at the end of the season.

If you are growing potted garden mums as perennials, repot the plant when it becomes root-bound about every two or three years. Potted mums do not adapt well to being moved indoors to grow as houseplants for the winter. They require some winter chill each year, so it's best to move your potted mums into a sheltered outdoor location, such as a cold frame or porch, for the coldest winter months.

Overwintering

In warmer climates (USDA hardiness zones 7 to 9), cut the plants back to about 6 inches after the fall-flowering period has ended. In colder climates (zones 4 to 6), it's best to leave the top growth in place and also apply a thick layer of dry mulch (straw, evergreen branches) over the plant to protect the crown over winter. In spring, cut off the dead stems to just above ground level.

Gardeners in cooler climates sometimes have good results overwintering outdoor mums by digging up and transplanting them into cold frames for the winter then moving back into their garden locations in the spring. Garden mums are notoriously fickle, so don't be surprised if your efforts at overwintering are not always successful.

Common Pests & Plant Diseases

Chrysanthemums have a natural resistance to many insects. An entire class of natural pesticides incorporates pyrethrin, which is derived from chrysanthemum flowers. But garden mums are still occasionally the target of small insects, such as aphids, thrips, spider mites, and leaf miners. If leaves show deformity, or if you notice fine webbing or trails on leaves, then using an organic pesticide such as neem oil is a good idea.

Garden mums are susceptible to a variety of diseases, including botrytis (a gray mold disease that causes flowers to shrivel), aster yellows (a viral disease that causes yellowing foliage), and several other fungal diseases such as powdery mildew, verticillium wilt, and leaf spots. It may be worthwhile to use a spray fungicide to treat fungal diseases, but often the best approach is to remove affected plant parts—or even entire plants if the disease is widespread. Avoid overhead watering to help prevent soil-borne diseases from spreading. Fungus only spreads on wet leaves, not dry leaves.

How to Get Hardy Mums to Bloom

Bloom Months

Hardy mums bloom primarily in the fall months but they can start flowering in the late summer.

What Do Hardy Mum Flowers Look and Smell Like?

Hardy mums come in many autumn shades and the plant includes layered, daisy-like petals or tight button-like blooms that have a compact, bushy growth. Hardy mums have a bit of a spicy fragrance with a hint of sweetness.

How to Encourage More Blooms

Hardy mums will usually provide robust blooms if their basic cultural needs are met: plenty of sun and water, and early pinching back of the stem tips to create bushy rather than leggy plants. Lack of flowering is often traced to deficits in sunlight or water.

Unlike many flowering plants that don't like extra feeding, hardy mums often do respond to extra fertilizer and will produce more and larger flowers.

Caring for Hardy Mums After They Bloom

If you bought potted hardy mums, plant them in the ground after the blooms fade, around late October. Water them well, mulch them, and cut them down to 3 inches from the ground for the winter. Do this with existing mums in the ground after blooming, as well. Protect them during freezes while newly planted mums establish their roots in the ground.

Deadheading Hardy Mum Flowers

Pinch the flowers of hardy mums by removing the tips of new growth to encourage side shoots for compact and bushier growth with profuse blooms. Spent flowers should be deadheaded to prevent the plant from becoming unkempt and to stimulate continued budding.

Start pinching in the spring when the new growth has reached roughly 6 inches long. Every two to three weeks, pinch back half of any new growth when it reaches 6 inches. Stop pinching chrysanthemums around the beginning of summer, around the Fourth of July, or else bud formation won't occur soon enough to ensure flowering for fall.

Common Problems With Hardy Mums

Garden mums are usually easy to grow provided they are given the right conditions, but they are relatively high-maintenance, so don't be surprised if some problems do arise. This is not a plant-it-and-leave-it specimen.

Yellow Leaves

Yellowing leaves on garden mums often signal a viral or serious fungal disease. The best solution is to cut away all affected plant parts—or even remove and destroy the entire plant before the problem can spread.

Leggy, Droopy Plants

If mums are not severely pinched back as they first begin to grow in the spring, the plants can easily develop long, leggy stems that collapse under their own weight. For best results, hardy mums should be pruned or pinched back severely at least twice in spring and early summer before the late summer and fall blooming season gets underway. Pinching back the plants will keep the plants from getting too tall and leggy.

Remember, too, that garden mums need a lot of sun, and if they are planted in shady conditions, the natural tendency will be for the stems to stretch to reach for more sunlight.

Plants Break Off at the Soil Line

It can be tricky to get the watering routine right with these plants. They need regular, reliable watering, but too much water, especially in soil that is too dense or has too much clay, can cause root rot that will soften the stems and cause the plants to break off. Make sure to adjust your watering routine based on how much natural rainfall is occurring. More than 1 inch per week might put your plants at risk of root rot.

FAQ
  • Can I plant a gifted flowering mum plant in the garden?

    Maybe. If it's a hardy garden mum, then it can probably be transplanted into the garden as a perennial, provided the variety is rated for hardiness in your climate. But if you received an exhibition-type chrysanthemum plant, it's unlikely it will survive. Such plants are often forced into early bloom under controlled lighting conditions, and they don't respond well to being transplanted into the garden. Enjoy a gifted mum while it's in bloom, then discard it.

  • How long does a garden mum plant live?

    Garden mums are relatively short-lived perennials, rarely living more than four or five years. At this point, the root clumps become overgrown and woody, and the plant dies. However, division of the roots every two or three years allows you to effectively keep the plant (or at least identical copies) growing indefinitely.

  • How should I use hardy mums in a landscape?

    Plant these fall-bloomers as annuals in the late summer and fall to replace fading summer-blooming annuals. Mums also make excellent potted plants for decks and patios. As perennials, they are useful as permanent bedding plants to keep the color display alive into the late fall.

The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Chrysanthemum x Morifolium. North Carolina University Extension.

  2. Mum. ASPCA.

  3. Chrysanthemum Diseases & Insect Pests. Clemson University.