Chrysanthemums are one of the easiest perennials to propagate at home, and the most reliable methods are stem cuttings and root division. Both are done in spring, and both can produce blooming plants the same year. Mums naturally become crowded every two to three years, so propagation doubles as essential maintenance for keeping your plants healthy and flowering well.
Cuttings vs. Division vs. Seeds
You have three options for making new chrysanthemum plants, but they aren’t equally practical. Stem cuttings and root division are the go-to methods for home gardeners because they produce genetic copies of the parent plant, meaning the flowers will look exactly the same. Both work in spring and yield plants that bloom by fall.
Growing from seed is less common for a few reasons. Most named chrysanthemum varieties are hybrids, so seedlings won’t reliably match the parent. Seeds also take longer to reach blooming size. If you want more of a specific mum you already love, cuttings or division will get you there faster and more predictably.
How to Take Stem Cuttings
Spring and early summer are the ideal windows for taking cuttings. Wait until the new shoots on your established plants are several inches tall, then cut the upper 3 to 4 inches of a healthy shoot with a sharp, clean knife. Make your cut just below a node, which is the small bump where a leaf attaches to the stem. This node is where new roots will emerge.
Strip the leaves from the lower half of the cutting. Dip the bare end into a powdered or gel rooting hormone. While chrysanthemums can root without it, rooting hormone significantly improves your success rate. Research on chrysanthemum varieties has shown rooting rates above 94% when hormone is applied, compared to noticeably lower rates without it.
Stick the cuttings about an inch deep into a rooting medium of coarse sand, perlite, or a 50/50 mix of peat and perlite. The key is good drainage. A waterlogged medium will rot the stems before roots form. Keep the medium consistently moist but never soggy, and place cuttings in bright, indirect light.
Expect roots to develop in about 4 to 5 weeks. You can test readiness by giving a gentle tug on the cutting. If you feel resistance, roots have formed and the plant is ready to transplant into the garden or a larger pot. Well-rooted cuttings establish themselves quickly and will bloom the same year they’re planted.
How to Divide Established Plants
Division is even simpler than cuttings and works best on plants that have been growing in the same spot for two to three years. The ideal moment is early spring, right when new shoots are 1 to 3 inches tall. At this stage, the plant’s energy is focused on root growth, and the divisions recover quickly.
Dig up the entire clump, working a spade around the perimeter to lift the root ball intact. Wash or shake off enough soil to see the root structure. You’ll notice that several small plants, each with its own roots and shoots, surround an older central portion. Cut these sections apart with a sharp knife or spade. Each division should have several shoots and a healthy root system.
Discard the old central portion of the clump. It’s woody, less vigorous, and won’t flower as well as the younger outer sections. Replant the divisions immediately in freshly prepared soil, spacing them 18 to 24 inches apart. Water them in well.
Setting Up the Right Growing Medium
Whether you’re rooting cuttings or potting up divisions, the soil mix matters. Chrysanthemums need a medium that holds some moisture but drains freely. A standard mix of roughly 45% peat, 25% bark, 15% perlite, and 15% vermiculite works well. For rooting cuttings specifically, you can simplify this to straight perlite, coarse sand, or a perlite-peat blend.
Always use fresh potting mix rather than reused soil or garden dirt. Pathogens that cause damping off (a fungal condition that rots young stems at the soil line) thrive in old, contaminated growing media. If you’re reusing pots or trays, soak them in a 10% bleach solution for 30 minutes and rinse before filling them. Clean your cutting tools the same way.
Keeping Cuttings Alive While They Root
The biggest threat to fresh cuttings is moisture loss through the leaves before roots can take up water. To prevent wilting, create a humid environment by placing a clear plastic bag or dome over the tray of cuttings. Open it briefly once a day to allow air circulation and prevent mold.
Warmth at the root zone speeds things up. If you’re rooting indoors, a heating mat set to 70 to 75°F under the tray encourages faster root development. Place cuttings where they get bright light but not direct afternoon sun, which can overheat them under a humidity dome. If you’re using artificial light, 12 to 16 hours of fluorescent or grow light works well.
Water with clean, room-temperature water. Cold water can shock young roots, and overly wet conditions invite the same fungal pathogens that cause damping off. The surface of the medium should feel damp to the touch, not wet. Pots with drainage holes are non-negotiable.
Garden Mums vs. Florist Mums
This distinction matters before you spend time propagating. Garden mums (sometimes called hardy mums) are bred to survive winter outdoors and bloom reliably each fall. These are the ones worth dividing and taking cuttings from year after year.
Florist mums, the ones sold as potted gift plants in decorative foil, are a different story. They’re not winter-hardy in most climates and are bred for a single season of indoor display. Propagating them is possible, but the resulting plants typically won’t survive outdoors and aren’t worth the effort for most gardeners. If the mum came from a florist or grocery store, it’s best treated as a temporary houseplant.
Pinching for Bushier Plants
Once your new cuttings or divisions are established and growing, there’s one more step that makes a big difference in how the plants look by fall. When stems reach about 8 to 10 inches tall, pinch or snip off the top inch or so of each shoot. This removes the single growing tip and forces the plant to branch out from lower nodes, creating a fuller, more compact shape with many more flower buds.
You can repeat this pinch one or two more times through early summer, stopping by mid-July in most climates. Pinching any later risks removing the developing flower buds, which form in response to shortening days. The result of consistent spring pinching is the dense, mounded shape you see on garden center mums, rather than the leggy, sparse look that unpinched plants develop.
Timing at a Glance
- Division: Early spring, when new shoots are 1 to 3 inches tall. Every 2 to 3 years.
- Cuttings: Spring to early summer, when shoots are several inches tall. Root in 4 to 5 weeks.
- First pinch: When new growth reaches 8 to 10 inches. Stop pinching by mid-July.
- First blooms: Same fall for both cuttings and divisions taken in spring.