Mums (garden chrysanthemums) · last checked 2026-09-27
When to plant mums: spring or fall, sun and cold hardiness
Garden centers fill up with blooming mums in fall, but the Extension pages we read point out that a mum planted in spring has a whole season to build roots before winter.
Each line below names the Extension service it comes from and links to their page. Where two services put it differently, both are listed.
When to plant
- Clemson Cooperative Extension says mums can go in during fall or early spring, and spring-planted mums grow into fuller, sturdier plants by the fall display. Chrysanthemums: How to Grow Garden Mums in South Carolina (HGIC 1161) · checked 2026-09-27
- Illinois Extension says most planting guides favor spring if you want mums to come back, because fall-planted mums enter winter with small roots. Fall planting is still common, since that is when plants are for sale. Planting and Maintaining Perennial Mums (The Garden Scoop, 2022) · checked 2026-09-27
Annual or perennial
- Clemson Cooperative Extension says garden mums are hardy perennials in South Carolina, though many people treat them as fall-planted annuals. Plants kept as perennials spread fast and should be divided every year or two. Chrysanthemums: How to Grow Garden Mums in South Carolina (HGIC 1161) · checked 2026-09-27
- Illinois Extension says mums are usually perennial in Illinois, but some cold winters kill them, mostly because their shallow roots can freeze as the top of the soil freezes and thaws. Planting and Maintaining Perennial Mums (The Garden Scoop, 2022) · checked 2026-09-27
Cold hardiness
- Clemson Cooperative Extension says garden mums are hardy across South Carolina, and its quick guide lists them for USDA Hardiness Zones 5a to 9b. Chrysanthemums: How to Grow Garden Mums in South Carolina (HGIC 1161) · checked 2026-09-27
- Illinois Extension says mums come through winter better when last year’s growth is left standing under a mulch about 4 inches deep, rather than being cut back in fall. Planting and Maintaining Perennial Mums (The Garden Scoop, 2022) · checked 2026-09-27
Sun and soil
- Clemson Cooperative Extension says mums want full sun and fertile, well-drained soil rich in organic matter. A mature plant set in shade may look fine the first year but does very poorly the next. Chrysanthemums: How to Grow Garden Mums in South Carolina (HGIC 1161) · checked 2026-09-27
- Illinois Extension says mums prefer full sun, more than six hours a day, and well-drained soil. A sheltered, south-facing spot helps, and outdoor lights close by can upset flowering. Planting and Maintaining Perennial Mums (The Garden Scoop, 2022) · checked 2026-09-27
Watering
- Clemson Cooperative Extension says mums need a lot of water, and most of all while they are in bloom. Chrysanthemums: How to Grow Garden Mums in South Carolina (HGIC 1161) · checked 2026-09-27
Unless a line says otherwise, weeks are counted from the average last spring frost where you live. Find that date through your state’s Extension service. See how these pages are put together.
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