Nothing short of a pile of pumpkins and a sheaf of corn says autumn like brilliantly-colored mums in a pot or garden bed. It takes just a few plants to create an irresistible accent.
Potted chrysanthemum plants, some “forced” into bloom in greenhouses before their normal flowering time, are sold by the millions at nurseries starting as early as September. Though some are capable of making it through the winter, many are not hardy varieties, and even fewer are likely to survive because they weren’t set out early enough to get established before frost. And even then, most eventually succumb to root-rotting rain and the sheer neglect of gardeners who see them as quick fixes for fall.
Still, chrysanthemums - Japan’s national flower, with huge displays arranged for National Chrysanthemum Day - are fantastic for working into interesting combinations and also mixed with other garden favorites. Because of their foliage and flower shapes and color, chrysanthemums combine well with sedum, salvias, Artemisia, basils, ornamental grasses and celosias. They are perfect for last-minute accents in containers, as border plants, or in fanciful floral clocks and other Victorian extravaganzas.
The bushy plants have aromatic, emerald-green foliage that can be long and lance-like, oval, and may be shallowly or deeply lobed or even feathery and fern-like, making even non-blooming plants important.
The sturdy, usually frilly flowers, which appear at the ends of stems and are classified according to shape (mop head, pompom, single, double and more), can be white, yellow, green, bronze, orange, red, pink, purple and countless bi-colors. Tall flowering varieties may need staking to keep them from flopping over under the weight of their own flowers, especially after heavy rains or overhead watering.
Plant Right for Longest Season
To get the most out of chrysanthemums in the garden, they need at least six or eight weeks in the ground to get established before flowering. Plant them in well-drained prepared soil, feed lightly once a month through mid summer with an all-purpose flowering plant fertilizer, and provide ample moisture without rotting them. Air circulation is important in keeping down foliage diseases. And apply a nice thick mulch to help keep soil cool and moist and to keep weed seedlings down. Hardy garden mums also need mulch to help them through harsh winters.
Once the plants start sending out nice new shoots, pinch or snip off the growing tips to make the plants bush out with more flowering stems. This can be done up until early July, after which the new growth should be left along to form flower buds in the fall.
Chrysanthemums are “short-day” plants, meaning they start setting flower buds when days start to get shorter. In some cases, those grown in mild climates can get enough head start on growing, they may bloom in the spring. Because of this, avoid planting chrysanthemums near bright night lights, which can throw off their blooming cycle.
If stuck in moist, well-drained potting soil, placed in bright indirect light, and kept humid with a greenhouse-like plastic tent, short tip cuttings of chrysanthemums will root very readily from late spring through mid summer. Mature plants can also be divided in the fall or spring.