Overwintering Mums: How To Keep Them Happy
Have you ever thought about overwintering your fall chrysanthemums? It's absolutely possible.
A shelf full of furiously blooming mums at the garden center has to be one of the most cheerful fall visions. Not only do they look incredible in pots, but they also make gorgeous mounds of blossoms in our flower beds. Most mums are treated as annuals. They're not particularly tough and are bred more for the beauty of their blossoms than for rugged-weather hardiness.
There are two distinct types of chrysanthemums. There are florist mums, usually the ones sold in pots in the fall; and garden mums or hardy mums, which can grow happily as perennials in your garden with some extra TLC. You can overwinter both, but they have different requirements.
How to Overwinter Hardy Mums
Perennial chrysanthemums should be planted in a well-sheltered spot in the spring to make sure they've had plenty of time to develop a robust root system before winter. Even hardy mums still need some specific TLC to make sure they survive.
Don't fertilize your mums after July. Otherwise, they may produce too much late-season growth.
In the fall, from mid to late November, mums will need to be covered well with mulch for the winter. Don't cut back the foliage; mums that retain their foliage through the winter are more likely to survive.
The most important thing is for your chrysanthemums to stay solidly frozen for the entire winter, which is why they need a good layer of mulch for insulation. The freeze and thaw cycles in fall and spring can cause significant damage to the roots of mums. Evergreen branches are excellent for mulching, as is clean straw or pine needles.
Whatever you mulch them with, don't remove the mulch until late March or early April.
Varieties of Hardy Mums
There are a few different varieties of hardy mums that will overwinter through our cold Zone 5b, so keep your eyes peeled for these in the nursery next spring.
We have many varieties of mums in every color. In the garden, most will reach 24” high and 36” wide in full to part sun.
If you have any questions about protecting your mums through the winter, come and chat with one of the horticulturalists at our Bettendorf store. We can help you make a plan for overwintering the mums you have, or advise on what varieties to plant outdoors next spring.