How to Propagate Mums in Water

Propagating mums (chrysanthemums) in water is one of the simplest ways to clone a plant you love, and the roots typically appear within two to four weeks. All you need is a healthy stem cutting, a clean container, and a bright windowsill. The science behind what makes a cutting successfully root, though, is more interesting than most gardening guides let on, and understanding a few biological details can meaningfully improve your success rate.

What You Need Before You Start

Gather your supplies ahead of time so the cutting spends as little time out of water as possible once it is taken. You will need a sharp, clean pair of pruners or scissors, a glass or jar (clear is best so you can watch root development), room-temperature water, and optionally a small amount of liquid rooting hormone or willow bark extract. Rubbing alcohol or hydrogen peroxide for sterilizing your cutting tool is worth having on hand too, since pathogens that cause stem and root rot in chrysanthemums are widespread and aggressive once they take hold.

Choosing and Taking the Right Cutting

The cutting you select matters more than almost any other variable. Look for a stem that is actively growing, green, and flexible rather than woody. Ideally it should be about four to six inches long with several sets of leaves. Avoid stems that are already flowering or setting buds, because the plant’s energy in those stems is directed toward reproduction, not root formation. New vegetative shoots from the base of the plant or side branches that have not yet bloomed tend to root fastest.

Make the cut just below a leaf node, the slightly swollen bump where leaves attach to the stem. This spot has a higher concentration of the plant hormone auxin, which drives adventitious root formation. Research on chrysanthemum cuttings has confirmed that auxin-related proteins are closely linked to root development at the base of the cutting.

Strip the leaves from the lower half of the stem. Any foliage sitting below the waterline will decay, cloud the water, and invite the very rot organisms you want to avoid. Leave two or three sets of leaves at the top. Those remaining leaves continue photosynthesizing, producing sugars that fuel root growth.

Step-by-Step Water Propagation

Once your cutting is prepared, the process itself is straightforward:

• Fill the container: Use room-temperature tap water. If your tap water is heavily chlorinated, letting it sit uncovered for 24 hours allows chlorine to dissipate. Filtered water works too, but mums are not especially sensitive to ordinary municipal water quality.
• Place the cutting: Submerge the bare lower nodes in the water, keeping the remaining leaves above the surface. If the jar opening is too wide and the cutting keeps falling in, stretch a small piece of plastic wrap over the top, poke a hole, and thread the stem through it.
• Change the water: Replace the water every two to three days. This keeps oxygen levels up and prevents bacterial buildup. Stagnant water is the single most common reason cuttings rot before they root.
• Wait and watch: Within the first week, you may see small white bumps forming at the nodes. These are root initials. By week two or three, thin white roots should be visibly extending into the water. Some cuttings take a full four weeks, so patience matters.

Resist the urge to handle or tug on the cutting to check root progress. The early root initials are fragile, and disturbing them can set the process back. Clear glass lets you monitor without touching anything.

Where to Place Your Cuttings

Light quality has a measurable effect on how well chrysanthemum cuttings root. Research has shown that lowering the ratio of red to far-red light significantly improves adventitious rooting in chrysanthemum cuttings, and that this effect works through the plant’s auxin signaling pathways.¹ In practical terms, this means bright indirect light works well. A spot near a window that gets plenty of ambient light but not hours of direct midday sun strikes the right balance. Direct, intense sunlight can also heat the water in the jar, which encourages bacterial growth and stresses the cutting.

Temperature matters too. Chrysanthemum cuttings root best at roughly 65 to 75°F (18 to 24°C). Cooler temperatures slow root initiation, while consistently warm conditions above 80°F can promote stem rot. A typical indoor room temperature during spring or early summer hits the sweet spot without any special equipment.

Why Some Cuttings Root and Others Don’t

If you have ever had one cutting root beautifully while the one next to it just sat there and eventually turned brown, genetics is likely the explanation. A large-scale study examining 188 different chrysanthemum genotypes found dramatic variation in rooting ability across cultivars. The coefficient of variation for root-related traits ranged from about 21% for average root diameter up to 67% for the number of root tips, confirming a strong genetic basis for how readily a given mum variety roots from cuttings.²

What this means for you is that some garden mums will root in water almost effortlessly, while others may struggle no matter what you do. Common garden mums sold at grocery stores and nurseries in the fall tend to be bred for ease of propagation, so they are often good candidates. Specialty or heirloom varieties, or those bred primarily for unusual flower forms, may be less cooperative. If a particular cultivar is giving you trouble, try taking several cuttings at once to improve your odds, and consider switching to soil propagation if water propagation repeatedly fails.

Preventing Rot, the Biggest Threat

The most common failure mode for water propagation is not a lack of roots but stem rot that kills the cutting before roots form. Root and stem rot caused by water mold organisms in the Pythiales group is a major threat to chrysanthemums worldwide. Recent research identified two particularly aggressive species that attack chrysanthemum stems and roots.³ These are not true fungi but water molds, and they thrive in exactly the warm, moist conditions that a jar of standing water provides.

You can minimize the risk with a few habits. First, sterilize your cutting tool before each use. A quick wipe with rubbing alcohol is enough. Second, change the water religiously, every two to three days at minimum. Third, if you notice the water turning cloudy or the stem developing a slimy, soft, or dark section near the base, act fast. Pull the cutting out, cut away the affected tissue with a clean blade, let the fresh cut dry for an hour, and place it in new water in a clean container. Sometimes you can save a cutting this way. Other times the rot has already moved too far up the stem, and starting over with a new cutting is the better call.

Adding a small piece of horticultural charcoal to the water can help keep it cleaner between changes. The charcoal absorbs some organic compounds that feed bacteria and fungi. It is not a substitute for water changes, but it gives you a buffer.

Do You Need Rooting Hormone

For most garden mums in water, no. Chrysanthemums are generally willing rooters, and the auxin naturally concentrated at the leaf nodes is usually sufficient. That said, rooting hormones can speed things up and improve the number and quality of roots that develop, especially for cultivars that are slower to root on their own.

Synthetic rooting hormones sold as powders or gels at garden centers contain auxins like indole-3-butyric acid (IBA) or naphthalene acetic acid (NAA). These work, but they are designed for soil propagation. Using powder on a water-propagated cutting is awkward because the powder washes off immediately. Liquid concentrate formulations work better for water propagation. You can dilute a small amount into the water according to the product label.

If you prefer a natural approach, willow bark extract is a well-studied alternative. Research on chrysanthemum cuttings found that willow bark extract improved the formation of adventitious roots and root branching, with the best results at a very dilute concentration.⁴ You can make a homemade version by soaking fresh willow twigs (any willow species) in water for 24 to 48 hours. The resulting “willow water” contains natural salicylic acid and trace amounts of IBA. Use it as the water in your propagation jar. It is not as potent as commercial hormone, but it gives cuttings a measurable boost and costs nothing if you have access to a willow tree.

When and How to Transfer to Soil

Roots grown in water are structurally different from roots grown in soil. Water roots are more delicate, whiter, and less branched. They work fine in water, but they need to adapt to soil conditions once you transplant. The transition is the second most common point where people lose their propagated mums, after the initial rot risk.

Wait until the roots are at least one to two inches long before transplanting. Longer roots handle the transition better. When you are ready, fill a small pot with a well-draining potting mix. Mums dislike sitting in soggy soil, and after weeks of water propagation, planting into heavy, water-retentive soil is a recipe for root rot. A standard potting mix with added perlite works well.

Make a hole in the moist soil, gently lower the rooted cutting in, and firm the soil around the stem. Water it thoroughly right after planting. For the first week, keep the soil consistently moist but not waterlogged. This gives the water roots time to begin adapting to soil conditions. Over the next two to three weeks, gradually let the soil dry out a little more between waterings, which encourages the roots to toughen up and branch. Avoid fertilizing for at least two weeks after transplanting. The new root system is not ready to handle concentrated nutrients.

Place the newly potted cutting in bright indirect light, the same conditions it has been growing in. Once you see new leaf growth at the top of the plant, that is a reliable sign that the roots have established and the cutting is growing on its own.

The Best Time of Year to Propagate

Spring and early summer are the ideal window for water propagation. The plant is in active vegetative growth, producing the kind of tender green stems that root most readily. The long days and warm indoor temperatures also favor faster root development.

You can propagate mums in water at other times, but expect slower results. In late summer, many mums are already forming flower buds, and those stems root less reliably. In fall, the plants you find at garden centers are already in full bloom, which makes them poor candidates for stem cuttings. If you buy fall mums and want to propagate them, your best bet is to enjoy the flowers, cut the plant back after it finishes blooming, overwinter it, and take cuttings the following spring when fresh vegetative growth appears.

One exception: if you receive a bouquet of cut chrysanthemums and want to try rooting them, go ahead. Strip the lower leaves, trim the stem fresh, and place it in water just like a garden cutting. Florist mums sometimes root successfully this way, though the success rate is lower because the stems may have been out of water for an extended time and the varieties are not always bred for easy vegetative propagation.

Water Propagation Versus Soil Propagation

Water propagation wins on simplicity and the satisfaction of watching roots grow through glass. Soil propagation, however, produces sturdier roots from the start and skips the sometimes-tricky transplant transition entirely. Professional growers almost always root chrysanthemum cuttings in soil or in sterile growing media like perlite or vermiculite, partly for efficiency and partly because soil-rooted cuttings establish faster once potted up.

For home gardeners, the choice often comes down to personal preference and how many cuttings you are rooting. If you want a handful of new plants from a favorite mum, water propagation on a kitchen windowsill is perfectly effective and fun to watch. If you are propagating dozens of cuttings, soil propagation in a seed tray with a humidity dome is more practical and produces more consistently vigorous plants.

You can also split the difference. Start cuttings in water so you can monitor root development visually, and transfer them to soil as soon as the first roots appear, rather than waiting for long root growth. This minimizes the time the cutting spends developing water-adapted roots while still letting you confirm that rooting has begun.

Propagating From Different Parts of the Plant

Stem cuttings are the standard method for water propagation, but mums also propagate from basal cuttings and division. Basal cuttings are shoots that emerge from the base of the plant at soil level in spring. These tend to root faster and more reliably than mid-stem cuttings because they are younger tissue with higher concentrations of natural growth hormones. If your mum produces basal shoots, those are your best material for water propagation.

Division, splitting an established clump into smaller sections, each with its own roots, is technically not water propagation. But if you divide a mum and one section has minimal roots, you can place it in water temporarily to encourage new root growth before potting it up. This hybrid approach works well for reviving weak divisions.

Leaf cuttings, which work for plants like African violets and succulents, do not work for chrysanthemums. A mum leaf placed in water will eventually rot without producing roots or new growth. You need a section of stem with at least one node for a chrysanthemum cutting to root.

What the Cutting’s Biology Is Doing in the Jar

When you place a chrysanthemum cutting in water, the plant undergoes a series of internal changes at the cut site. Cells at the base of the stem begin to de-differentiate, meaning they lose their original identity and become capable of forming new root tissue. This process is driven primarily by auxin, a hormone that accumulates at the base of the cutting due to gravity and the plant’s own transport mechanisms. Proteomic research on chrysanthemum cuttings has identified specific auxin-induced proteins that are positively correlated with adventitious root formation, along with other proteins involved in stress response and energy metabolism.⁵

The cutting is also under stress. It has been severed from its water supply, its root system, and its nutrient source. The remaining leaves are photosynthesizing to keep it alive, but the cutting is essentially running on reserves. This is why keeping only a few healthy leaves is important: too many leaves create water demand the cutting cannot meet, while too few leaves starve it of energy. Two to three sets of leaves is the practical compromise that gives the cutting enough photosynthetic capacity without overwhelming it.

Light plays into this process beyond just providing energy for photosynthesis. The study on red and far-red light ratios demonstrated that specific light wavelengths influence rooting through their interaction with the plant’s auxin signaling, adding a layer of complexity that explains why some window placements work better than others.¹ Practically, indirect light filtered through a window or through a canopy of nearby plants delivers the kind of light spectrum that seems to favor rooting over direct, unfiltered sunlight.