Chrysanthemums, or mums for short, provide intricate, colourful flowers in fall gardens. Mums bloom after most other summer flowers have already faded. While chrysanthemums are perennial flowers in warm climates, they often are grown as annuals in areas with winter freezing because they don't survive prolonged cold. These flowers come in a variety of sizes, including dainty 6-inch-tall plants to large 4-foot-tall giants. Chrysanthemums are available in nearly any colour desired, with bicolored varieties also a choice. Plant seedlings in spring after all frost danger is past or plant mature mums in mid-to-late summer.
Spread a 2-inch layer of compost over a full-sun, well-drained garden bed. Work the soil into the top 8-to-12 inches of soil to add drainage and nutrition. Break up any large soil clumps so the mum's roots can spread.
Water the soil in the pots until it drains from the bottom. Lift the mum plant out of the pot.
Dig a planting hole to the same depth as the pot and slightly wider. Space each hole 15-to-24 inches apart.
Set the mum into the planting hole. Add or remove soil from under the root ball until the plant sits slightly deeper than it was in its pot. Refill the hole around the mum's roots with soil.
Water the chrysanthemum immediately after planting so any air pockets in the soil collapse. Moisten the soil to a depth of 6-to-10 inches at this initial watering.
Water mums once weekly, moistening the soil to a 6-inch depth. No irrigation is necessary if at least 1 inch of rain falls during the week.
Pinch off the top half-inch of each growing stem to help encourage branching and a full plant. Pinch plants before June; otherwise the process could inhibit flowering.
Weed between the mum plants at least once weekly, since these flowers do not tolerate weed competition. Break up the top half-inch of soil to prevent weeds from rooting.
Spread a 2-inch layer of mulch around the mums to help prevent weed growth and retain soil moisture. Use an organic mulch, such as wood chips or shredded bark.
Fertilise mums one month after planting with a complete fertiliser applied at the recommended rate on the package. Fertilise a second time once the flowers begin opening in fall.
Remove the side buds from each flower stem to encourage the mums to produce a single large flower suitable for cutting. Plant mums in pots and bring them indoors in winter to protect them from freezing.