Hardy groundcovers can create a carpet of late season color in your garden. So many low-growing perennial plants bloom in spring, but a few choice groundcover plants start their bloom season in the heat of summer. These late season beauties can light up the ground with their sizzling colors.

Are you, like a hummingbird, attracted to fiery red? Then Orange Carpet California fuchsia (Zauschneria garrettii) is certain to catch your eye. The plant is four inches high and two feet wide, demands little water, and begins its summer fireworks in mid-July. The plant is covered with masses of tiny, scarlet, trumpet-shaped flowers until frost. Best of all, the Plant Select® program has determined that Orange Carpet California fuchsia is as hardy as it is beautiful. Plant Select® is a cooperative program involving Denver Botanic Gardens, Colorado State University Cooperative Extension, and Rocky Mountain area landscape and nursery professionals. It seeks out the very best plants for Colorado gardens. Plant Select® has tested Orange Carpet California fuchsia and seen that it can thrive in full to partial sun at elevations up to 9000 ft and make it through an Idaho winter.

Two other Plant Select® perennial plants, Starburst ice plant (Delosperma floribundum 'Starburst') and Winecups (Callirhoe involucrata), are groundcovers that provide strong late season color. Starburst ice plant is a mounding, sun-loving, low-water plant that produces shimmering neon pink flowers with bright white centers from June until frost. The metallic-looking flowers are born on four-inch stems, and the plant grows to a width of ten inches.

Winecups, in contrast to the petite proportions of Starburst ice plant, is a giant groundcover. Although winecups achieve a height of only ten inches, the plant quickly attains a width of three feet, which makes it a good choice for sloping sites where erosion can be an issue. Most importantly, winecups magenta, cup-shaped flowers dazzle from spring until frost. The plant is native, hardy, and easy to grow with low to moderate water and full to partial sun.

If you can't get enough of hot pink, you might want to plant some desert four o'clock (Mirabilis multiflora). This plant was used by Native Americans for centuries as a medicine and a dye, and no doubt, it was also admired by them for its beauty. Bright pink, long, tubular flowers cover the plant from mid-summer to frost, but at mid-day, the plant hides its glory, closing its flowers tight until afternoon. Desert four o'clocks are sprawling plants which reach a height of about a foot and spread to three feet in sunny, dry conditions.

What if you crave a cooler color in the dog days of summer? Try fleece flower (Persicaria affinis). Throughout much of the summer, this plant is adorned with feathery spikes of pale or rose pink flowers that dry to a nice bronze as the season wears on. The blooms rise above a thick mat of durable, leathery foliage. As fall approaches, the green foliage also turns a lovely bronze color. Fleece flower performs well in sun to part shade with moderate water. A variety of fleece flowers cultivars exist, some only growing to nine inches in height and spreading to about eighteen inches.

If you would like a cool color with a big impact, plumbago (Ceratostigma plumbaginoides) may be the late-season groundcover for you. This gorgeous plant with an ugly name features peacock blue flowers on shiny green leaves through the latter part of the summer. As fall approaches, the leaves turn a delightful burgundy color. 8-12 inches high by 12-18 inches wide, plumbago can grow in full sun or in fairly shady sites with moderate water. The plant's adaptability makes it a great option for planting beneath shrubs, trees, or taller perennials. However, if you put plumbago in your garden, don't be surprised if you see no sign of the plant in the first months of spring. Plumbago is slow to emerge; perhaps it needs to sleep late after all its hard work in the fall.

Groundcovers that bloom from the late summer to the fall perform a vital role in keeping a garden looking good through the entire season. With the right selection of plants, your garden can be carpeted with blooming groundcovers even during the hottest of summer.

Q: I have been hearing a lot about the Asian longhorned beetle lately. Does this insect occur in Colorado?

A: No, Asian longhorned beetle, Anoplophora glabripennis, has not yet been detected in Colorado. Asian longhorned beetle is one of 36 species of Anoplophora native to Asia. The larval stages of these insects bore in the wood of a wide range of broadleaf trees and shrubs. In China, Asian longhorned beetle is an important pest of healthy, vigorous poplars and maples. These beetles can be so abundant in parts of China, that one method of control is for workers to climb into poplar trees, collect the emerging beetles and kill them in a jar of kerosene. Workers are paid on the basis of how many beetles they kill.

Infestations of Asian longhorned beetle were first discovered in the U.S. in 1996 in Greenpoint, Brooklyn, NY and, later, about 40 miles further east in Amityville, NY. Two years later, an infestation was discovered near Chicago. More recently, infestations have been discovered in New Jersey and Windsor, Ontario, Canada. Work is underway to eradicate these infestations, a program which, sadly, involves the removal and destruction of infested maples and other shade and ornamental trees, many of which have been in place for 40-50 years. The beetles probably arrived in wooden packing crates or pallets containing items imported from China.

A related beetle, known as the citrus longhorned beetle, Anoplophora chinensis, has been intercepted in several locations in the U.S. but is not believed established. This insect can attack many species of fruit trees as well as forest trees and has been intercepted from bonsai imported from Asia.

Q: Do insects occur in Colorado that could be easily confused with the Asian longhorned beetle?

A: Yes. The native Colorado insect that is most often confused with Asian longhorned beetle is the white spotted pine sawyer, Monochamus scutellatus. This wood-boring beetle of pines, Douglas-fir, fir, spruce and larch is found across much of the U.S. and Canada.

Another insect that could be confused with Asian longhorned beetle is the cottonwood borer, Plectrodera scalator. Like the Asian longhorned beetle, this insect breeds in poplars. Cottonwood borer is most common in the southeastern U.S. but can be found in Colorado and other western states.

Q: How can Asian longhorned beetle, white spotted pine sawyer and cottonwood borer be distinguished?

A: All of these insects are members of the beetle family Cerambycidae or longhorned beetles, a large family of striking, colorful beetles. They have long antennae, often 1.5 to 2 times as long as the body. All breed in the stems or root systems of woody plants and adults are often seen on feeding on flowers. Both the Asian longhorned beetle and white spotted pine sawyer are large beetles and are shiny black in color. The easiest way to distinguish the two is to examine the antennae. Asian longhorned beetle has antennae with alternating white and black bands whereas the white spotted pine sawyer typically has black antennae. The elytra or wing covers of the Asian longhorned beetle are shiny black with distinct white markings. The elytra of the white spotted pine sawyer tend to have white markings that are smaller and less distinct. Some individuals have no white markings on their wing covers.

The cottonwood borer is also a large beetle. It is black in color with patches and cross stripes of fine, pure white hairs and almost resembles a Halloween skeleton.

Q: Is the white spotted pine sawyer a serious pest?

A: The white spotted pine sawyer is not a serious pest in North America. This beetles confines its attacks to stressed or dying pines and other conifers. Attacks can also occur in freshly cut logs and larval borings can cause loss of lumber quality and structural integrity. The larvae of these insects are often found in firewood. If firewood is stored in the home, you can hear the larvae chewing in the wood. Sometimes the adults can emerge from firewood stored in the home. Most people finding one of these striking beetles, with long antennae, on their living room wall will be concerned. The best thing to do is gently guide them to the nearest doorway and out into the open.

Adult pine sawyers feed on young pine shoots. Some individuals carry life stages of a parasitic pinewood nematode on their bodies. The feeding can result in inoculation of the tree with pinewood nematodes. Since the pinewood nematode is native to North America, our native conifers are not affected by this parasite. However, the pinewood nematode has been accidentally introduced into parts of China and Japan. Pines native to these countries are killed by the nematode and significant damage has occurred. Several species of pine sawyers native to China and Japan have become important agents in the spread of this nematode.

Note: If you suspect that you are seeing an Asian longhorned beetle instead of one of our native longhorned beetles, capture the beetle and place it in a dry, empty jar. Take the beetle to your nearest Colorado State University Cooperative Extension office or Colorado State Forest Service Office for identification.

Ground cover plants can make interesting and functional landscape design elements. They are especially useful in areas where turf is not a practical choice or on slopes where soil erosion is a problem. CSU Cooperative Extension's Fact Sheet 7.400 - Ground Cover Plants provides detailed information on ground cover selection and care.

Conserve resources and help your turf by applying water slowly enough to avoid puddles or runoff. Use multiple, shorter applications to allow water to soak into the soil more thoroughly.

To really understand how your soil affects the health of your plants, it helps to know more about its composition. A simple texture test is to squeeze a moist handful of soil in your fist. Sandy soil will fall apart, while clay will form a ball.

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

Gardening and Insect Fact Sheets are available on-line by clicking HERE.

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This page updated:  August 23, 2004