Chrysanthemum Care Guide: How to Grow Chrysanthemums

Chrysanthemums, also called “mums” or “chrysanths” for short, are a genus of flowering plants in the Asteraceae family. The name comes from two ancient Greek words: chrysos (gold) and anthemon (flower). Many species of chrysanthemums are native to China, though some have also been found in northwestern Europe and Japan.

Chrysanthemums have large flower heads with a proliferation of petals, though there are also varieties of mums that are more daisy-like with smaller petals. Chrysanthemums usually have yellow, orange, purple, red, or white flowers. They are fall flowers, typically blooming in the late summer or fall, and some varieties are annuals while others are perennial plants.

There are more than 20,000 cultivars of chrysanthemums, but the genus can be categorized into two broad types: garden mums and florist mums. Garden mums are hardy perennials that will survive outdoors in hardiness zones 5 to 9. Florist mums are used for indoor potted plants and won’t survive transplanting to a garden.

Chrysanthemums make up an entire genus, so there are countless species and varieties, with the most chrysanthemum cultivars coming from China. To make it easier for gardeners, the U.S. National Chrysanthemum Society has classified mums into 13 bloom forms. These include:

1. 1. Regular incurve: These mums have petal florets that completely cover the center of the plant and all curve inward to form a ball shape.
2. 2. Single and semi-double: These mums look like daisies, with one row or double row of petals surrounding a center.
3. 3. Anemone: These mums look similar to a semi-double, but the center floret is large, plushy, and raised.
4. 4. Pompom: Also called pompon, this is a smaller type of mum with rows of petals that completely conceal the center. The flowers usually grow one to four inches.
5. 5. Spider: Spider mums have long, tubular petals that sometimes have hooks at the ends.

Garden centers and florists typically offer mums in early spring, which is when you should plant them. You can plant mums directly from the container or from cuttings. You can also grow mums from seeds:

• Start the seeds indoors before transplanting outside. To avoid variations in temperature and sunlight outdoors, it's best to start chrysanthemum seeds indoors. Transplant when the seedlings are a few inches tall and the spring weather outside is warm. Plant seedlings eight inches to three feet apart in your garden.
• Direct sow the seeds after the last frost. If planting seeds directly in your garden, freely sow the seeds in the spring well after the last frost.
• Plant chrysanthemums in well-drained soil rich in organic matter. If your soil needs nutrients, add some compost and phosphate to support the plants’ roots. If you want to fertilize your mums, a standard garden fertilizer will do.
• Surround the seedlings with mulch. Whether growing from seeds or transplanting seedlings, cover the soil lightly with mulch to keep it moist. Seeds will sprout 10 to 15 days after sowing.
• Plant chrysanthemums in a location with direct sunlight. Mums need full sun for at least three hours a day, but ideally six hours a day.
• Water consistently. Keep the top layer of soil most for the plants’ shallow root system. After planting in the spring, give your chrysanthemums one inch of water per week.

Chrysanthemums will continue to bloom and sprout from season to season with care. Follow these tips to keep your mums healthy throughout the year:

• Keep the soil lightly moist. As the plant grows bigger in the summer, water as frequently as needed to keep the soil lightly moist—as much as three times a week.
• Prune chrysanthemums to promote growth. Pruning can encourage bushier growth and more flower buds. When the plants are around six inches tall, pinch off the tips of the stems once a month.
• Protect your chrysanthemums from pests. Mums are sensitive to pests like aphids and diseases such as powdery mildew. Prevent the spread of pests and mold by spacing your plants out in the garden. Allow for good air circulation between the leaves, and water the plant close to the ground so the leaves don't get wet.
• Allow dead leaves to accumulate around your plants. These hardy perennials will survive the winter and come back next year with the help of dead leaves as insulation for the roots. Apply a thick layer of mulch (chopped leaves, pine needles, etc.) around the base of the plant. If necessary, water the mums throughout the winter so the soil stays moist. When spring arrives after the frost, pull back the mulch and dead leaves. Then watch as new shoots sprout up.
• Overwinter your chrysanthemums indoors. Overwintering your mums inside is an option if you live in a particularly cold climate. Dig up the mums and keep them in a pot indoors, and make sure the soil is moist, not soggy.

Chrysanthemums can be propagated through offset division and cuttings:

1. 1. Offset division: If you’ve had a chrysanthemum bush for a few years, dig up the plant and its roots in the spring for propagation. Divide the plant into pieces about a foot wide, then plant the pieces in new holes.
2. 2. Cuttings: When a new stem is 6 inches’ tall, cut off the top 4 inches. Plant the cutting in a pot of potting soil or a mix of sand and peat moss. Keep the pot moist in a place where it will get plenty of bright, indirect light. The roots will form in two weeks, after which you can replant them in a bigger container or outside in your garden.

Chrysanthemums are toxic to pets and can cause vomiting and diarrhea. If your pet has eaten a chrysanthemum, call your vet. Certain mums, though, are safe for human consumption. Flower petals from the species C. morifolium or C. indicum can be boiled to make chrysanthemum tea and are very popular across Asia. Korea also makes a rice wine flavored with chrysanthemum flowers called gukhwaju.

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