When to Plant Garden Mums
Light up autumn scenery with the floral fireworks of garden mums. These fall favorites ignite a landscape with blazing color. Many gardeners treat garden mums like annuals, using them to decorate porches and planting beds for a short growing season. Few plants bring on the autumn color like these pretty bloomers.
What garden mums often fail to deliver is winter survival. If you’re a gardener who’s tucked fall garden mums into planting beds only to have them die, you’re not alone. Armed with a few tips, you can improve your odds of making garden mums a perennial part of your landscape.
The first step is to buy the right kind of mums. Not all garden mums are created equal in terms of surviving winter cold. Prior to the 1960s, most garden mums were perennial and easily survived winter in Zones 5 and 6. Intense breeding efforts since then have created a wonderful selection of flower colors and forms, but the eye candy often occurs at the expense of a hearty constitution.
When buying garden mums, look for tags that say hardy mums or garden mums, as opposed to the less hardy florist mums or cutting mums. Mammoth daisy garden mums were developed at the University of Minnesota and are hardy to Zone 3. Plants open daisy type blooms with petals surrounding a gold center. Colors include red, yellow, lavender, bronze and coral.
Once you have the right kind of garden mums, planting at the right time is the other crucial step to helping them survive winter. If you typically plant garden mums when you clean out your containers after frost, you might as well toss them on the compost pile. In cold regions, this is too late to plant mums and expect them to survive winter.
The best time to plant fall purchased garden mums is the minute you buy them, which should be as soon as you see them for sale. Early planting—even as early as late August—helps plants develop a strong root system. Plant garden mums too late, and winter freeze-thaw cycles can shove plants out of soil, a condition known as frost heave. Without early planting to permit strong root growth, shallow rooted garden mums don’t really stand a chance.
After planting garden mums, don’t forget to water throughout fall. It’s also wise to add mulch at planting time over plant roots. Once soil freezes, add another mulch layer around the base of garden mums to help insulate soil and prevent frost heave. Chopped autumn leaves form a good mulch, as does shredded bark. Don’t clip dead stems until spring.