Mums, commonly known as Chrysanthemums, are among the most recognizable flowering plants of fall. Their rounded shape and colorful flowers make them popular for garden beds, porch containers, borders, and seasonal displays.
Most garden mums sold today are cultivars of Chrysanthemum × morifolium, a cultivated perennial hybrid in the Asteraceae family. Plants typically form dense mounds about 1 to 3 feet tall and produce flowers in a wide range of colors and forms.
Mums naturally begin developing flower buds as days become shorter and nights become longer. This makes late summer and fall their main flowering season. However, care can vary depending on whether you are growing a hardy garden mum or a florist mum sold primarily as seasonal decoration.
This guide covers everything you need to know about caring for mums, including lighting, watering, soil, temperature, fertilizing, pruning, blooming, winter care, and common problems.
Image: @Katerina Maksymenko
Basic Information
| Feature | Details |
|---|---|
| Botanical Name | Chrysanthemum morifolium |
| Family | Asteraceae (Daisy family) |
| Plant Type | Herbaceous flowering perennial |
| Mature Size | 1 to 3 feet tall, 1 to 2 feet wide |
| Sun Exposure | Full sun (6 to 8 hours daily) |
| Soil Type | Well-draining potting mix |
| Soil pH | 6.0 to 6.5 (slightly acidic) |
| Bloom Time | Late summer through fall (August to November) |
| Flower | Wide range of colors: white, pink, red, yellow, purple, and bi-colors |
| Hardiness Zones | USDA zones 3 to 9 |
| Native Area | East Asia (China, Korea, Japan) |
| Toxicity | Toxic to cats and dogs if ingested |
Should we grow Mums (Chrysanthemum) indoors or outdoors?
Indoors, mums thrive when placed near a bright window with plenty of natural light, making them ideal for fall decorating during their peak blooming season. They prefer cooler indoor temperatures and benefit from good air circulation, so placing them away from heating vents helps extend their flowering period.
Outdoors, mums truly shine in garden beds and borders where they receive full sun and have room to spread. They're more likely to return year after year when planted in the ground with proper drainage and established in the landscape before winter arrives.
General Care
1. Lighting
Mums prefer full sun, ideally at least six hours of direct sunlight each day.
Strong sunlight encourages dense growth, sturdy stems, and abundant flowering. Plants grown in too much shade may become tall, loose, or floppy and generally produce fewer flowers.
In very hot climates, some protection from intense afternoon sun can help reduce heat stress.
For indoor potted mums that are already blooming, place the plant near a bright window. Bright light helps maintain flowers, although harsh midday sunlight through glass may cause the pot to dry very quickly.
2. Watering
Mums prefer consistent moisture, especially while actively growing and flowering.
Water thoroughly when the upper layer of soil begins to feel dry. Continue watering until excess moisture drains from the bottom of the pot.
Do not allow the plant to remain completely dry for long periods. Mums have relatively shallow root systems and can wilt quickly, particularly when grown in containers. Potted mums may need to be checked daily during warm, dry weather.
Avoid constantly soggy soil. Good drainage is essential because prolonged wet conditions can damage the roots.
3. Soil & Fertilizer
Mums grow best in fertile soil that retains some moisture while still draining freely.
Garden soil can be improved with organic matter before planting. For container plants, use a quality potting mix in a pot with drainage holes.
A soil pH around 6.0 to 6.5 works well for most mums.
Feed established mums with a balanced fertilizer during spring and early summer while they are actively producing stems and leaves. Reduce or stop fertilizing once flower buds begin developing.
Avoid excessive fertilizer, which can encourage tall leafy growth at the expense of a compact shape.
4. Temperature & Humidity
Mums prefer cooler temperatures between 60°F and 75°F, which is why they perform so well in fall and as indoor plants during cooler months. They appreciate moderate humidity and good air circulation, so a small fan in the room can help prevent fungal issues.
5. Toxicity
Chrysanthemums are toxic to cats, dogs, and horses. Chrysanthemum species as containing sesquiterpene lactones, pyrethrins, and other potential irritants. Ingestion can cause vomiting, diarrhea, drooling, loss of coordination, and skin irritation. Keep potted mums away from pets that are likely to chew foliage or flowers.
Image: @Jeni Joseph
Extra Care
1. Potting & Repotting
Potted mums need containers with drainage holes because their roots prefer regular moisture but cannot tolerate standing water.
When repotting, choose a container only slightly larger than the existing root ball and use fresh, well-draining potting soil.
Mums planted into the garden should be placed at approximately the same depth they were growing in their nursery pot.
For perennial growth, spring planting is preferable because the plant has an entire growing season to establish roots before winter.
2. Pruning
Pinching is one of the best ways to produce a compact mum covered in flowers.
Once new spring growth reaches around 4 to 6 inches tall, remove approximately the top ½ to 1 inch of each growing stem. Repeat as new shoots grow to encourage additional branching.
Stop pinching in early summer, commonly around late June or early July in many climates. Continuing too late can remove developing flower buds and delay fall blooming.
Deadhead faded flowers during the blooming season to keep the plant looking tidy and encourage the remaining buds to continue opening.
3. Propagation
Mums can be propagated by division or stem cuttings.
Established garden mums benefit from division every few years. Divide the plant in spring when new shoots begin emerging, removing old woody sections and replanting healthy young divisions.
Stem cuttings can also be taken from healthy new growth during spring or early summer.
Keep newly propagated plants evenly moist while their root systems develop.
4. Blooming
Chrysanthemums are classic short-day plants, meaning flower bud formation is triggered as nights become longer in late summer and fall.
This natural response explains why mums produce their main display toward the end of the growing season. Artificial light at night can interfere with the darkness period and delay or reduce flowering. Avoid planting garden mums directly beside strong porch lights or other nighttime lighting.
Adequate sun during the day, regular watering, and correct pinching also support heavier flowering.
Remove faded blooms regularly to extend the appearance of the flowering display.
5. Seasonal Care Tips
- Fall and Winter: Keep mums in cool locations (between 60°F and 70°F) to prolong blooming, and refer to our Winter Care Guide for tips on protecting outdoor plants and managing indoor specimens through the colder months.
- Spring & Summer: Water regularly during warm months, fertilize every couple of weeks, and start pinching back growth in late spring to shape plants and increase bloom count for the coming fall.
Common Problems
Mums are generally forgiving plants, but they can struggle with root rot if overwatered, spider mites if the air is too dry, and aphids or whiteflies in indoor settings. Watch for yellowing leaves, webbing on stems, or sticky residue as signs of pest or moisture problems, and address them promptly with appropriate watering adjustments or organic pest treatments.
Succulents Box's Tips
- Mums sold in grocery stores and garden centers during fall are often treated as annuals, but with proper care, they can be overwintered and reflowered the following year outdoors in the right climate.
- Pinch back growing tips every two to three weeks from spring through mid-July to create fuller, bushier plants that produce more flowers in fall.
- Move potted mums to a cool, well-lit spot indoors for the longest blooming period, and rotate the pot every few days so all sides receive equal light.
- Water at the soil level rather than overhead to keep foliage dry, which reduces the risk of fungal diseases and leaf spotting.
- Provide bright light indoors but protect mums from intense afternoon sun through a sheer curtain if they're in a very hot window.
Image: @Lialina Olena
