You see them at the grocery store, the farm markets, the big box stores—those domes of autumn colors in yellow, bronze, reds and dusky pinks–the Chrysanthemums. For a quick color show that stands up to light frost, they’re a great decorator boost for entryway containers or walkway beds.
I didn’t really know much about mums. On occasion, I’d been given some old potted Mother’s Day mums at a swap and told to plant them–they’d grow from the foliage into nice plants the following year. Not so fast. It seems that the expectation for florists mums is to treat them as annuals. They’ve been pinched and prodded with botanical chemicals to put on a flower show, but not to grow the essential rhizome roots that will keep them alive and growing into the cold season. What you want is “garden mums” that are ordered as plugs or quart sized plants and set into your garden in May. These will behave like proper perennials and reward you in fall with 6 to 8 weeks of showboating flowers.
There are hardy fall mums, also referred to as Korean mums or Chrysanthemum indica which often have a daisy shaped flower. Chrysanthemum morifolium includes large growers to 36 inches like the “Football mums” and smaller growers of button mums plus in between sizes. There are also carpet mums like Chrysanthemum weyerichii and all kinds of cultivar crosses.
I have grown Korean mum crosses from seed with success and tried planting spent pots (failure). Next step was to order garden mums from a reputable company. In this case, I went with Bluestone Perennials who have a good reputation for plants and customer service. The only thing I didn’t care for was the coir pots they are using so right away I sliced those pots on several sides to allow the roots access to my soil and prevent any possibility of the mum drying out inside the pots. I ordered tall, medium and short growers in a range of colors and put them in a grow bed in my veg garden to trial them. Some I ordered were Whipoorwill, Yellow Valor, Pure Delight, Little One, Homecoming, French Vanilla and Drummer Boy.
Mums are very tolerant of soil pH as long as the drainage is good, especially in the winter. They like a fairly rich soil with compost and prefer full sun to thrive and flower their best. It is recommended to pinch your mum growing tips back a couple times in the summer. Mine started flowering in July, to my surprise, so I sheared them all back once since I wanted to concentrate on getting those rhizomes to grow a bigger plant. By late summer all the mums I’d purchased were bursting with new buds. Don’t cut the spent foliage back until spring and if you have a frost heave problem in winter, mulch them. Mums may need to be divided and set into improved soil approximately every three years to reinvigorate them.
If you are interested in exhibition mums, you can learn how by joining the Chesapeake Chrysanthemum Society chapter which has many members in Maryland. They are having an October show at Longwood Gardens–this weekend!