By almost any measure, garden chrysanthemums (Chrysanthemum x morifolium) are garden winners. Mums are easygoing, beautiful, fresh-scented, hardy and happily transplanted while in full bloom. They come in a mix of colors, shapes and heights. Some variety is in bloom from the end of August through November, and the flowers hold up well when cut.
But while many folks buy a couple of pots of mums to plop on the porch in September, those who don’t stick them in the ground are missing out on a dependable perennial. Of course, like many other cultivars in these mountains, mums’ hardiness can depend on location. But if you’re buying potted mums anyway, why not give it a shot?
While the more exotic varieties can grow successfully outdoors, the more common types are more consistently durable. The principal problem with exotics — anemone, cascade, spider, spoon, quill and others — is that they bloom late and are therefore more prone to frost damage. The easiest to grow are the button, decorative, pompon and single-flower types, and within these varieties are hundreds of cultivars and a wealth of colors to choose from. Except blue. No blue mums. Sorry. (Some gardeners go to the enormous trouble of lifting mums and tucking them in cold frames. Sigh. Isn’t there something you’d rather be doing on a perfectly nice Saturday?)
To do well, mums require a rich, well-drained soil with a fairly neutral pH and consistent moisture. For best blooming, side-dressing with compost or rotted manure through the season or occasional watering with manure tea (made by soaking manure in water for a couple of days) is a must. Even then, your homegrown plants may not exhibit the density of flowers found on their chemically dosed supermarket cousins — but they’ll more than make up for it when you inhale their pungent odor without sucking up a snoutful of organophosphates.
Chrysanthemums are best divided in the spring. Prune old, woody growth in favor of the more succulent new growth. Pruning during the growing season (up until midsummer) helps create a more compact bloom display, and the cuttings root easily. Tall varieties benefit from staking. And although all varieties will bloom in light shade, full sun will generate more flowers.
Mums are prey to many of the usual garden culprits but not overly so. For example, while thrips shriveled most of my glads and roses one season, nearby mums were unaffected — perhaps because of the much later bloom cycle.
Two close relatives of morifolium, the nipponicum and rubellum, are also winter-hardy in our region. The first offers a white bloom (2-3 inches in diameter) that’s much like a Shasta daisy; the latter produces somewhat larger pink, daisylike flowers. Like garden mums, nipponicum is divided or grown from cuttings; rubellum on the other hand has purple rhizomes that spread quickly. They form beautiful clumps of flowers in any reasonably decent soil and in anything from full sun to light shade.