If you are like me, you succumb to the pleasure of buying a few fall mums early each fall. I enjoy placing them near my front entryway as a welcome to the new season. I love their vibrant colors and their plentiful blooms. I also enjoy their affordable prices – one store near me was selling small garden mums for $1 each recently. You can pick them up on big box stores and supermarkets and often roadside stands pop up selling moms and pumpkins this time of year.
The trouble is many people treat these hardy plants as throwaway fall decorations. Did you know you can successfully overwinter fall mums both in the ground and in pots? Here’s how.
Outdoors in the ground
The first step to successfully overwintering garden mums is to plant them in the ground early. Many gardeners purchase mums to replace fading annuals in their garden in late summer. Since mums are one of the last perennials to bloom, this is a good idea.
A key to the mum’s survival of the winter is to plant it in the ground well before the first frost. Mums that are planted in late summer or very early fall have a better chance of surviving harsh temperatures because their roots will have some time to establish in the ground. This prevents frost heave when the ground freezes.
Choose a sunny somewhat sheltered spot that drains well. Work about an inch of chopped leaves or other organic matter into about a foot of loosened soil. Also, work in a granular fertilizer that is formulated for mums.
Water your transplants well and cover them with about two inches of mulch (chopped leaves or bark mulch work well) for protection. This will also protect the soil from freezing and thawing quickly during rapid temperature changes.
As fall progresses, the leaves of your mum will start to turn brown. As the foliage dies, cut it back. You can trim the stems to about three to four inches above the ground.
Provide more mulch, such as leaves or straw, after the first freeze. If any additional foliage has been killed by the cold, do not trim it away until spring. It will help provide insulation to the plant throughout the winter. Many people like the neatness of a trimmed perennial bed, but those dead stems provide essential protection for the roots.
In the spring, remove some of the extra mulch as the mums begin to grow again. Carefully divide the plant when new shoots reach about four inches tall. Plant these new plants about 18 to 24 inches apart.
Bringing mums indoors
Another way to overwinter mums is to bring them indoors for the cold months. Choose a mostly dark cool area, such as an unheated garage shed or basement, which has temperatures between 32 and 55 degrees Fahrenheit. If temperatures could fall below freezing, wrap the pots with several layers of newspaper to protect the roots.
Water your mums so that the soil is slightly moist. Repeat throughout the winter once a week or so when the soil feels dry about two inches down. Don't keep the soil soggy, the roots will rot when it is cold and damp. Dormant plants need very little water to survive.
About a week or two before the last expected frost, take the pot outdoors to a sunny location for a few hours of afternoon sunshine each day. Then bring it back to its winter location for the night. After the threat of frost has passed, leave the pot in its outdoor spot.
Water thoroughly and apply a granular fertilizer. Within a few weeks, you should start to see some new growth.
Garden mums are “photoperiodic,” which means they bloom in response to the shorter days and longer nights of autumn. Individual flowers can last from three to six weeks depending on how much water the plant receives and the temperatures to which the plant is exposed. The flowering period is shorter with high temperatures and little water so remember to give your containerized mums plenty of moisture to keep them at their best for the longest time.
Garden mums range in size and shape from low, tight mounds to tall plants. Popular cushion mums, which have a mounded, pincushion-like look, usually grow no more than 20 inches. These mums are available in a wide variety of colors from traditional fall golds, reds and purples to soft pastel colors. There is usually a color combination to coordinate well with any type of decorations and they are so inexpensive that you can create a wonderful show for very little money.
With a little care, mums can add a great splash of color to your garden – both this fall and in coming years and a little care and planning will reward you with long lasting benefits.