DALLAS GARDEN BUZZ

There’s no doubt about it—the rose is the world’s most popular and acclaimed flower. Valentine’s Day is a natural time to think of roses, a symbol of love and beauty.

We are receiving or buying them for loved ones and also thinking about roses grown in our own gardens. Dallas gardeners know to prune their roses around February 14th.

Sadly my pruners will be on the shelf; my roses have fallen prey to the disease for which there is no cure, rose rosette disease (RRD). Instead I will be making  decisions about replanting my roses or planting perennials instead of roses.

Stephen Hudkins, Dallas County Extension Agent, Horticulture, Texas A&M AgriLife Extension Service, encouraged me by reminding me that rose rosette has been around a long time and that other cities under its siege have eventually recovered. He also counseled me to plant a few roses and think of them as one- or two-year plants. Remove them if rose rosette returns.

Rose Buff Beauty to be replaced

We also have counsel from Maddi Shires who has answered several questions regarding Rose Rosette. Maddi is a graduate student, working on her PhD in Plant Pathology and Microbiology with Dr. Kevin Ong, Associate Professor & Extension Plant Pathologist, Dept of Plant Pathology & Microbiology and Director – Texas Plant Disease Diagnostic Laboratory, Texas A&M AgriLife Extension Service. Her research project is Rose Rosette Disease Resistance in Texas. The Raincatcher’s Garden has planted a research plot of 40 roses as part of her study. Here’s what Maddi shared with me:

Howdy Ann,

1) The gardeners that I have talked to are doing one of two things to replace their roses: Many are taking the chance and replanting more roses again. This could be a good idea for those who love roses, and many are willing to buy roses year after year to replace what was lost. There are many varieties that should be avoided, such as the Knock Out^® rose family, Julia Child™, and Home Run^® family, just to name some of the more prominent roses I’ve seen used in mass plantings in Dallas. The other thing that people are doing, especially those who do not want to have the cost of purchasing roses each year, is that they are moving away from roses and towards other plants.

2) I would never tell someone to not plant roses, however if they do not want to treat roses as a 1-2 year plant, people may not want to go back with them. In Dallas County and the surrounding counties, the disease incidence is high, and until we have identified a tolerant or resistant variety, it is likely that roses will have shorter lifespans when planted back in areas that have already had virus-infected plants.

3) As of right now, we have not identified any tolerant or resistant varieties, so if you enjoy roses and will be able to remove them if they become infected, I would recommend planting them! There is no reason to not enjoy a plant as long as you can remove it and properly dispose of it if it is infected by the virus. There are rose rosette trials going on all over the United States, and results are varied for many rose varieties. I have three varieties that I did not see infection in in the first 6 months of my trials—those were Basye’s Purple, Caldwell Pink, and Chuckles. Chuckles has been reported to have symptoms from a public garden in Dallas, so it may not be a good alternative. Stormy Weather, Carefree Spirit, and Sydonie are some others that have been suggested as tolerant. If you plant roses that are these varieties or others and they become infected, please let me know because we are doing a variety list of infected roses.

4) I have not heard of anything specific that people are planting to replace roses. I would recommend doing research on plants before planting them to see if they have disease problems. For example, many people replace rose gardens with boxwood but boxwood has problems with blight, which requires treatment and can kill the plant.

As always, if you suspect that your rose may have rose rosette disease, please send a sample into the Texas Plant Disease Diagnostic Clinic. Many times there are other plant problems confused for RRD, and plants are taken out that may not need to be. When removing plants, make sure to bag all plant material, dig up the roots, and properly dispose of the plant material.

Thanks,

Maddi Shires

Rose Replacements:

• Althea (Rose of Sharon). I want to try the smaller variety, Lil’ Kim
• Quince. There are so many varieties
• Loropetalum, Chinese Fringe Flower. The color of the leaves replaces the red in your landscape if you lost Knock Out roses
• Perennial Hibiscus. Try Hibiscus ‘Moy Grande’ for big color
• Texas Superstar^® plants

Ann Lamb

Rose rosette disease trials are in the early stages and nothing conclusive has been determined. If you read conflicting advice or have further questions, please respond back to us. Dallas Garden Buzz will respond.