A curb-appeal crowd pleaser, colorful chrysanthemums are one of the perkiest signs of fall. They even have a subtly spicy scent that fits right in with the season of pumpkin lattes! It’s no wonder, then, that not just nurseries but big-box stores and supermarkets, hawk buckets of these showy plants as soon as September rolls around. For the most part, however, these “florist mums,” as they are called, aren’t especially robust—they don’t propagate or overwinter very well, so all too often they’re trashed after their blooms start to wither.
The good news is that “garden mums” are true perennials that are as hardy as they are handsome. Relatively easy to grow and care for in USDA hardiness zones 5 to 9, garden mums can return season after season. And once they get a successful start, mums are simple to divide and root wherever you may want to add pops of cheer.
So just say no to unnecessary plastic container waste and use this guide to grow your own chrysanthemums. Your garden will look gorgeous come next autumn as you give new meaning to the expression: Mum’s the word!
Explore the Many Types of Mums
Mums bloom in late summer and tend to be tough enough to stay in full flower through fall’s chill. They come in a spectrum of hues, from yellow, white, purple, and pink through true autumn shades of orange, burgundy, and bronze.
According to the National Chrysanthemum Society, there are 13 different varieties of mums, each displaying a different petal shape and length, including:
- Decorative mums, with their small, flat, incurved florets, are perhaps most common.
- Spider mums have long, elegant petals that look like spider legs.
- Reflex mums have downward-curving florets and a somewhat flat center.
- Anemone mums have a raised center resembling a pincushion.
- Single and semi-double mums look a lot like daisies.
- Pompom mums, as the name implies, have a tight ball shape.
The shape of the plants also differs to suit various landscapes areas. For example, low-growing “cushion mums” are perfect for carpeting a slope, while taller types, such as quill mums, can grow up to 3 feet high and make a pleasing backdrop to a flower bed. Taller varieties are also ideal to use as cut flowers. (Tip: split the stem ends of cut mums so they can better absorb water in a vase.)
Choose One of the Three ways to Propagate Mums
Spring is the ideal time to give mums a good start. There are three approaches to begin growing mums: with seeds, by division, or from cuttings.
- Growing mums from seed: If you don’t have access to existing mums or want to add a new variety or different color to your landscape, purchase garden chrysanthemum seeds. Plant them indoors in late winter/early spring (six to 10 weeks before the last frost date is due in your climate). Use a good potting mix and keep it moist (not wet) and maintain a temperature of about 70°F to 75°F. Seedlings should appear within 10 days to two weeks—just be sure to give them adequate indirect light. Then Epic Gardening advises to “harden off” seedlings by slowly exposing them to the outdoors a little at a time before transplanting them to a sunny spot in the garden.
- Growing mums by division: The easiest way to propagate mums is simply by harvesting from a healthy clump of existing plants and re-rooting them. Choose plants that have flourished for several years and are at least 6 inches tall. In the spring, gently dig around the roots and separate out individual stems, keeping roots intact. Replant the divided mums in flower beds or containers, about 18 inches apart (they’ll spread!).
- Growing mums from cuttings: Try this method to start a new crop of mums from younger plants as long as stems are at least 4 inches tall. Cut stems with a sharp knife at a 45-degree angle and remove all leaves from the bottom as well as any flowers or buds. Kickstart growth by placing the cuttings in root hormone, then plant them in pots, using a perlite-and-compost mix, vermiculite, or even sand. Then water and keep the pots in a humid environment, if possible. The cuttings should establish roots within two to four weeks, at which point they can be transplanted into containers or directly to the garden.
Nurture Mums Correctly for a Bounty of Fall Flowers
While garden mums aren’t persnickety plants, they do have specific needs in terms of soil, light, water, and nutrients. Treat them right and they should stand up to pests, resist disease—and reward you with loads of color come autumn.
Mums can flourish in most soil types that drain well, though a neutral to slightly acidic pH is best. Topping off the soil with a bit of homemade compost ought to keep mums happy.
Let there be lots of light
If you want a lot of blooms, plant mums where they can get full sun outdoors—a solid six to eight hours of direct light every day.
Don’t forget to water
Chrysanthemums have shallow roots that can dry out fast, and being in direct sun can also parch them, so water regularly, being careful not to let the soil dry out. Continue to water in the fall after flowers wither, which will help the plants survive the winter.
Give them a boost
Mums don’t need much coddling, but fertilizer can help them develop strong stems and profuse flowers, while also preventing plants from budding too early. Feed mums during the vegetative stage to deliver the nitrogen and potassium that helps develop roots. Then fertilize before buds begin and again before summer heat kicks in—however, this will vary according to the fertilizer formula you choose and whether mums are in garden earth or containers.
Pinching and pruning
Good grooming will keep mums looking their best. Pinching off the tips of new stems by a few inches, every couple of weeks through mid-July, will keep plants compact and rounded, while also promoting ample buds.
Once flowers wither and leaves yellow at the end of fall, prune further down to prepare mums for winter—go all the way to an inch above the ground if you live in a warm climate, or leave stems a bit taller in colder areas to give roots a bit more protection.
Protect against pests and disease
While mums may fall prey to aphids, snails, slugs, and spider mites, among other garden banes, encouraging natural predators such as ladybugs and lacewings can control these common pests. A number of pesky diseases may infect mums, leading to yellowing, spotting, browning, and stunted growth. To help stave off these issues, Gardenia advises ensuring that the soil drains well, plants are amply spaced for circulation, and foliage is checked regularly for early signs of disease.
