Rose Disease Hits Botanic Garden Roses
Gripping a long-stem rose, Tim Henson inspected the bloom for the telltale sign of rose rosette disease.
Stems covered with thorns. Leaves crinkled and puckered. Deformed buds with multiple shoots that turn a hue of red.
“It’s an uphill battle right now,” said Henson, a rose gardener at the Fort Worth Botanic Garden. “You plant a bush and four months later have to rip it out. The disease is everywhere.”
Rose rosette has ravaged neighborhood entrances, front lawns and suburban landscapes in North Texas, which experts say is the hardest-hit area in the country.
The Dallas Arboretum has ripped up dozens of infected rosebushes in recent months, and a master rosarian has trained the staff to spot the disease, said Dave Forehand, vice president of gardens for the Arboretum.
“Rose rosette is an epidemic, and North Texas is the epicenter,” Forehand said. “This is a game changer for roses, I’m sad to say.”
Southlake is removing and replacing more than 5,400 rosebushes in medians and parks because of the disease. Costs could reach $500,000, city officials have said.
But in few places is the devastation more evident than at the Botanic Garden’s acclaimed Rose Garden, where gardeners have ripped up hundreds of diseased rosebushes.
“We call it Y&R, yank and replace,” said Steve Huddleston, the garden’s senior horticulturist. “We have to keep an eye out constantly.”
‘Highway for the mites’
Known as witch’s broom for the spindly appearance it leaves behind, the disease is caused by a virus carried between plants by microscopic mites that blow in the wind.
Rose rosette arrived in North Texas more than three years ago, but this year has been particularly difficult, Huddleston said.
Officials at the Botanic Garden were forced to speed up the second phase of a sweeping renovation because of the rapid spread of the disease, for which there is no cure.
Crews have removed infected roses around the Oval Rose Garden, Republic of Texas Rose Garden and Lower Rose Garden and are regularly applying a miticide to bushes to try to prevent the further spread of the disease.
In late June, gardeners ripped up roses that line the Rose Ramp and are now improving the irrigation system. This month they will plant periwinkles, hibiscus, purple fountain grass and other seasonal flowers to provide splashes of vibrant color as the soil recovers. And this fall, when the temperature drops, roses should return, albeit fewer than before.
To limit the disease’s reach, Huddleston said, the garden’s new design will space out rosebushes, interspersing them among other perennials and annuals.
“All of these rosebushes planted together creates an interstate highway for the mites,” said Henson, who is a member of the American Rose Society. “They can have a field day.”
Inspired by central Italy’s renowned Villa Lante garden, the Botanic Garden’s Lower Rose Garden was built in the 1930s and is on the National Register of Historic Places.
‘A grand European garden’
Even before rose rosette hit the garden, it had begun to show its age, Huddleston said, as wood on structures was rotting and walkways cracking.
The city-owned Botanic Garden and the Fort Worth Garden Club, a support arm of the garden, joined to complete more than $1 million in renovations, which included repaving walkways, replacing wood on the gazebo and other structures, adding a new fountain, replacing the pump system in the big pool and adding boxwood hedges and topiary to the displays.
The first phase was finished in fall 2014, and the second is nearing completion.
“When we’re done,” Huddleston said, “the garden will look like a grand European garden.”
For now, crews have placed signs around the garden to educate visitors about rose rosette and explain the absence of the signature flower.
“This garden has been here for generations. When people think of the Botanic Garden, they think of the Rose Garden,” he said. “People have gotten married here, gotten engaged here. It’s a dear spot for many people.”
Sarah Bahari, 817-390-7056
Rose rosette disease
▪ Rose rosette is a disease spread by microscopic mites carried by the wind. Infected plants’ leaves and twigs become bright red and may be distorted. Diseased plants can grow so many thorns that the stem is not visible.
▪ However, symptoms are variable on different roses. For example, red shoots do not occur in some ornamental rose varieties and there is a lack of excessive thorns on multiflora roses. Knock Out roses are especially prone.
▪ Experts say the only way to get rid of the disease is to dig up each infected plant, down to its roots. Put them (roots and tops) into trash bags and make sure they get to a landfill. Do not try to compost them, and don’t try to remove the diseased shoots selectively. If you do, you will help spread the disease.
Source: Star-Telegram research