PREFERRED SOIL pH: Near neutral
PREFERRED SOIL TYPE: Well-drained, fertile
PREFERRED LIGHT: Sun to partial shade
ATTRIBUTES: Flowers in white, yellow, pink, red, and purple; use in containers or beds
SEASON OF INTEREST: Fall
FAVORITES: Multicolored Prophet series; 'Single Apricot' to grow as a perennial
QUIRKS: Blooms when days become short in the fall
GOOD NEIGHBORS: Asters, ornamental cabbage and kale, ornamental grasses, pansies
WHERE IT GROWS BEST: All climates and exposures
POTENTIAL PROBLEMS: Aphids, grasshoppers
CRITTER RESISTANCE: Good except for grasshoppers
SOURCE: Stem cuttings, division
DIMENSIONS: Potted mums less than 18 in (45.7 cm) tall, 15 in (38 cm) wide
Chrysanthemum in the Landscape
Chrysanthemums are the benchmark annuals for fall, whether grown in containers or beds. The "garden mums" sold in late summer bloom outdoors with enthusiasm and also make long-lasting cut flowers, staying fresh in a vase for 2 weeks or longer.
Many mums make fine garden perennials. These are usually different varieties from the mums that have been bred to provide instant fall color on leafy, well-branched plants of uniform size. Perennials include the many-colored Prophet series, 'Red Bravo', dark lavender 'Debonair', and numerous yellows including 'Jessica' are also popular. The longest-lasting bloomers will have the word "decorative" on the plant tag. This describes the flower form, a dahlia-type blossom packed with petals, in which the new petals emerging from the center of blossoms magically give week-old flowers a freshly opened appearance.
If you live in Zones 6 to 8, try growing cold-hardy chrysanthemums as perennials. At 30 in (76.2 cm) tall, 'Single Apricot', also known as 'Hillside Sheffield Pink', requires little care and puts on a beautiful show each fall. For best results, order starter plants from mail-order catalogs and plant them in early summer so that they will be well rooted by winter.
When buying fall-blooming mums, select plants covered with buds. To reduce the frequency of watering, move mums into slightly larger pots. You can display mums in a shady spot, but shade sometimes causes the flowers to open unevenly. If you want to overwinter a potted mum, let it dry out and turn brown, but do not trim off the dead stems. Move the pot to a cool place and water to keep the soil barely moist. If the plant survives, small green shoots will appear at its base in early spring. Trim off the dead stems just before setting out the plant shortly after your last spring frost.
To keep growing plants compact and encourage maximum flowering, cut them back by half their height in midsummer. For more mums, simply insert the cuttings into a pot of damp potting soil, set it in a shady place and keep the soil moist until the cuttings show new top growth, then transplant them into the garden. If plants begin to set buds before you want them to, delay flowering by pinching off buds up to the middle of August. If plants become crowded, divide and replant as you would any perennial.
Except for small sap-sucking thrips and aphids, and grasshoppers, mums have few pest problems. Knock thrips and aphids off with a spray of water or apply the botanical insecticide neem as directed. Handpick grasshoppers, or tolerate their damage, because they are unstoppable in a populous year. Mums growing in hot, humid conditions can contract fungal ray blight, which causes flowers to turn brown and limp. Replace affected plants with healthy ones.