Planting fall flowers
September 7, 2010
  • /Crop Sciences
Chrysanthemums, pansies and ornamental kale can add color to a drab fall garden, said a University of Illinois Extension horticulture educator.

"Chrysanthemums have been cultivated for more than 1,500 years and come in a wide variety of colors and types," Jeff Rugg said. "They flower in many varia¬tions of yellow, gold, pink, white, red, bronze and purple. The flowers can be smaller than one-inch buttons or two-inch pompoms, but can grow as large as six-inch decoratives. These flowers also come in many shapes, from daisies to round, many-petaled balls.

"These plants can grow as compact 10-inch mounds to plants that are several feet tall with stems suitable for cutting and placing in a vase," he said.

Growing garden mums is relatively easy: they prefer full sun, require soil that drains well and has a lot of organic matter, and only need to be fed once or twice during the summer.

To encourage more flowers, pinch off one inch of growth on each stem every time they grow to six inches long. If you do not pinch them back, they tend to get leggy and fall over on their side. Stop pinching after mid-July.

Mums can be divided each spring by digging up the whole plant. Discard the middle and replant the vig¬orous new shoots.

"Although mums are best planted in mid- to late May, you will not be sure what color flowers you are getting,' Rugg said. "Many garden centers have a small amount of mums in the spring but stock up in the fall when they are blooming. While garden mums are hardy in northern states, those planted during the fall will sustain winter damage that may kill them.

"Mums sold by florists as decorative pot plants are usually not hardy at all but can be fun to experiment with," he added.

To protect garden mums from winter damage, wait until the top has been killed by frost. Cut the dead top off about two inches above the ground.

After several frosts, cover the plant with six to eight inches of mulch. This stops the alternating cycles of freezing and thawing that can kill the root stock. Remove about half of the mulch in the spring as the plant begins to grow.

Pansies grow well during the cool fall season. Across the southern states, pansies bloom from fall through the winter and spring until the weather turns hot. In northern states, they can be planted in the shade, where they will bloom all summer if they stay cool and moist. Pansies are annuals, which typically die after a weather condition causes them to go dormant.

"But the newest pansies on the market can survive being frozen during the winter and will rebloom in the spring," Rugg said. "For best results, protect the plants with snow cover or a layer of mulch that is several inches deep. Icicle pansies are some of the best-suited plants for northern United States winters."

Pansies are less than a foot tall. The flowers are generally about two inches across, but some varieties have flowers four inches across. Some new varieties have single colored flowers, but most pansy flowers have at least three colors, ranging from dark to light blue, purple, red, white and yellow. They look best in large masses of a single color or with a pair of opposite single-colored flowers, such as a mass of yellow with a blue border. Another good use for pansies is in pots where they can be seen up close.

The only soil requirement for pansies is that it be well drained. Soil that retains water or ice will kill the plant.

"Our third fall color plant is a biennial that is grown for its ornamental leaves rather than its flower," Rugg said. "Two interchangeable varieties in the same species are called ornamental kale and ornamental cabbage. Kale does not form a head, but the cabbage does. They have leaves that start out white or pink and eventually turn green or purple. This gives the plant a unique appearance, with the new color in the center and the older-colored leaves surrounding it."

Even though they are grown for ornamental purposes, some varieties are also edible. These plants need the same growing conditions that a garden would provide. They prefer a moist, well-drained soil and plenty of sunlight. They also need cool temperatures and will survive frosts and snow.

"If left to grow too long, ornamental kale and cabbage will lose the old leaves at the base of the plant. The newer leaves will be left on top of an ugly stalk," Rugg said. "The best ornamental display is when they are planted close together. The heads will just about be touching when the display is first planted."