"With shrub and landscape roses you can be less selective. With these kinds, you can trim them off with hedge shears, if you want. Just keep the spent blossoms removed to encourage more blooms. Remember that even ever-blooming roses go through cycles and have more blossoms at certain times of the year."

Since our wet June has brought out some seldom-seen disease problems, I asked him to share information on disease control.

"The key to controlling diseases is to learn about the diseases," Walheim said. "Learn what causes them, and then try to prevent them.

Rose black spot and rust prefer warm, humid conditions, while powdery mildew thrives with hot days and cool nights.

He recommends several cultural practices to help prevent diseases.

"Clean up the roses both as you deadhead and in the fall. Most of the diseases overwinter on fallen leaves and twigs. Avoid overhead watering, and if that is not possible, water early in the morning so the foliage has a chance to dry off before evening.

"Watch your plants carefully. If you see black spots appearing on the roses, pull off all the affected leaves. Hopefully, as the weather conditions change, most of the diseases will disappear.

More serious cases might require fungicides.

"Most fungicides prevent disease, and once a plant has a serious disease, it is difficult to control the outbreak. Organic controls include potassium bicarbonate or neem."

Of course, no interview with a rose expert could be complete without some favorite recommendations.

"I like the Floribunda 'Iceberg' and 'Home Run,' a shrub rose that is more resistant to powdery mildew than 'Knockout.' I also like 'Hot Cocoa,' which is an unusual color. It took some getting used to, but it looks wonderful with other colorful yellow and orange flowers. Altissimo is an excellent climbing rose."

He lists some other favorite shrub roses that resist black spot and other diseases on his Web site, www.lancewalheim.com.

Several local favorites include Bonica, Carefree Beauty, Carefree Delight, Carefree Wonder and Sally Holmes.

For those who want something even more cold-hardy he recommends looking at some of the new roses out of Minnesota or Canada. The Explorer roses are named after famous Canadian Explorers.

Garden tips and events

For a list of recommended varieties and other rose-growing information, contact the Utah Rose Society at www.utah-rose.com.

Larry A. Sagers is a horticulture specialist for the Utah State University Extension Service at Thanksgiving Point.