Keeping Fall Mums From Year to Year

The other day a customer remarked that her “hardy” mums never make it though the winter. Has this happened to you? As we explained to this customer, there are a couple of things going on. In some areas these plants are called “hardy” because they will withstand light frosts through the fall. On Cape Cod, however, most of these plants can also live through the winter and become perennials in the garden.

If you want your mums to live from year to year, here are a few tips for making sure they survive the winter. First of all, be sure to water the plants well at least once a week, especially after the flowers fade. Many people stop watering their newly planted mums once blooming stops, but if we have over a week of sunny, dry weather, those plants will dry up. Remember that any new plant has a root system the size of the pot, and this means that these roots will dry out more quickly than an established plant. So keep track of the rainfall and water new mums once a week through November or even early December in a warm season.

Secondly, for the first year anyway, leave the stems and leaves in the garden over the winter even if they have turned brown. This seems to help some new plants survive a first winter. You can cut the old stems back in March or April. In fact, in April you’ll probably see the new growth coming from the ground when you’re cutting the old stems away!

Some mums will be fuller if they are sheared in May. Clip the top inch or two off of the plants with scissors or a shearing tool anytime from mid-May through mid-June. Don’t shear later than the end of June, however, as this may delay flowering until very late fall.

And finally, there are many people who enjoy having mums in the fall but don’t have the space for them to be perennial garden plants. If this is your situation, sink the potted mum in the ground and after it’s finished flowering pull the pot out of the ground and empty the old plant into your compost. It’s perfectly acceptable to think of these plants as fall annuals!