Even though cases of impatiens downy mildew were confirmed in 33 states in 2012, growers are planning to produce Impatiens walleriana this year. However, Bill Calkins, business manager independent garden centers at Ball Horticultural Co., says in areas of the country where the disease was most prevalent, growers are reducing production of impatiens by about 10 to 20 percent.
“The Southeast and Northeast had the worst outbreaks,” Calkins states. “The Midwest was probably the next area that saw more cases of the disease. There are some areas that didn’t have any problems last year and growers are continuing to produce impatiens again this year.”
In areas like the Northeast where cases of the disease were widespread, Calkins says growers are reducing production of impatiens, but not eliminating the crop altogether.
Hard to Find Impatiens in Florida
Dave Self, owner of Wyld West Annuals in Loxahatchee, Fla., says most of the small- to medium- sized growers he has spoken with in his state have eliminated Impatiens walleriana from their product mix. Landscapers make up the majority of Self’s customer base.
“It just wasn’t worth the risk,” Self says. “You could get a bad reputation. You could run into problems if you say you are not guaranteeing them. It just wasn’t worth the effort to try to grow impatiens this year.”
“It was a problem in 2011, but it really hit hard in 2012,” he shares. “The disease is hard to get rid of. Once you have it, you have it. You can do preventive maintenance. But the homeowners and landscapers are not going to spend the amount of money for the rotation of chemicals for a 60- to 70-cent impatiens plant.”
“You might as well plant something that doesn’t get the disease,” he suggests. “And that is kind of what we did with geraniums, begonias, pentas, New Guineas, salvia, marigolds and gazanias. All of those minor crops sold because there weren’t any impatiens available.”
Opportunities for Alternative Crops
Calkins says growers who are selling to landscapers in areas affected by impatiens downy mildew are trying to make sure their customers are aware of the disease and are increasing their assortment of alternative crops.
“The silver lining on this is all of the great alternative products that are out there that have been underused because impatiens have been considered the go-to crop,” he says. “Many growers, landscapers and consumers have become dependent on impatiens as the primary shade plant. Growers are not eliminating impatiens, but they are encouraging their customers to diversify with some of these alternatives, including vegetative and seed-produced New Guinea impatiens and coleus, SunPatiens, a variety of begonias including fibrous and Dragon Wing, caladiums, dusty miller and torenia.”
Calkins says his company is going to keep growers updated on the disease and provide them with the information on how to control it. The company also has developed a list of alternative crops.
“We have gotten a lot of requests from growers and retailers about alternative crops, especially New Guinea impatiens,” Calkins shares. “We have been doing culture clinics on these crops. We want the growers and retailers to understand these alternative products as well as they understand and know impatiens. Impatiens sales may be down, but sales of these other crops are up.”
According to Self, one positive is that landscapers have become willing to try different crops.
“The only change that the landscapers weren’t happy about with the switch to some of the vegetatively-propagated plants like New Guineas was the additional cost,” he says. “Also, in regards to some of the alternative plants there is a little more maintenance like having to dead-head salvia, geranium and marigolds. But with other crops like New Guineas, SunPatiens, begonias and pentas, you just plant them and let them grow. They might not give you the same blast of color as the impatiens, but overall the change has been very positive.
Controlling the Disease
Michigan State University plant pathologist Mary Hausbeck has been working with growers in her state to be sure they know about the disease and what they can do to control it.
“We have growers all along the spectrum,” Hausbeck says. “Some are feeling confident that they have the disease under control and are going to produce the crop and supply impatiens as they have done in the past. Then there are others who are really worried because they don’t have the confidence in using the recommended fungicide programs or they may have had problems with the disease last year and feel overwhelmed.
“My sense is some of the largest growers intend to grow impatiens and fill contracts they have for the crop. Many of these growers have experience with the fungicides for downy mildew based on what they did last year. The large growers are doing what they can to minimize their risk from the disease.”
Hausbeck says some growers are still feeling their way through the fungicide programs that have been recommended by universities like Michigan State and Cornell and companies like Ball Horticultural and Syngenta. She says some of the fungicides in these programs are not part of standard control programs for other pathogens so in some cases both chemical suppliers and growers are not familiar with them.
“The ornamentals industry is trying to become familiar with some of these fungicides that its members have not used before,” she says. “Last year some distributors did not have all of the needed downy mildew fungicides in stock. Some are not broad-spectrum types or they are not widely used or they are more unknown because they are relatively new. In some instances, a distributor may have suggested using a replacement or substitute product that may not be especially effective against impatiens downy mildew.
“When a recommended treatment program comes out and is agreed upon by pathologists for downy mildew, it is really important to stay true to the products that have been proven to be effective by those who have tested them. Even though a product may be labeled for downy mildew control, that does not mean it will be effective against this particular downy mildew. That is why growers need to follow the recommended programs and not make substitutions.”
Hausbeck suggests those buying impatiens from growers in areas where the disease has been confirmed should ask if the growers have a downy mildew control program in place. She said the next question should be what chemicals are the growers using?
“Check to be sure the chemicals being applied are the same ones on the programs that have been recommended by the pathologists,” Hausbeck adds. “A chemical with similar chemistry to a product on an approved program list may or may not be effective against this disease.”
Educating End Users
Calkins says it should be easier to work with consumers in regards to offering them alternative shade crops that they may not have considered.
“Consumers are likely to get excited about plants that they may not have seen before or may not have considered before,” he shares. “It may be a tougher sell to landscapers who have become accustomed to putting in large beds of impatiens and who may be less willing to try something new. They might be able to replace impatiens with as many as five different products. That can create all kinds of issues, but it can also offer landscapers a lot of opportunities.”
Calkins says it is important that retailers not scare their customers about the disease so that they stop buying plants altogether.
“Independent garden centers can become an information source discussing the disease with their customers and allowing them to decide whether they want to buy impatiens,” he says. “The garden centers can also provide information to consumers as to why there aren’t as many impatiens available this year. They can also position themselves as the experts in trying to show consumers how to use impatiens in hanging baskets and containers. If garden centers are in areas that had high disease pressure last year, they can recommend that customers not put them in a garden bed this year, but offer them some alternative crops to use instead.”
Self says he is encouraged by the interest landscapers have shown in the alternative crops, especially since the vegetatively-produced ones are more expensive than impatiens.
“It’s going to take a few years to educate people for them to see the results before they will be completely sold on some of the new plants that they haven’t tried before,” says Self.
“Since landscapers have been forced to use different crops they seem to be more open to trying something new. I have grown different crops from Proven Winners, Syngenta and Athena Brazil, including lobelia, cleome, argyranthemum and verbena. The landscapers have never used these plants. They buy 50 to 100 plants and try them and then they come back and buy more. They tell me the plants did well and look really nice.”
Hausbeck, who has held several meetings about the disease with Michigan growers, says she is also planning to meet with landscapers this year.
“When I meet with the landscapers this will be the first time for me to address this group,” she says. “I have a sense that I’ll need to build a foundation by providing the landscapers with biological and control information.”
During her meetings with growers, Hausbeck was told the growers are hoping to be more proactive with the landscapers and help to guide them in regards to what some of their options could be for landscape plantings.
“The landscapers need to recognize that this disease is a problem and it is treatable with the right tools (see Table 1),” she says. “But if they don’t have the right tools or don’t use the right tools early and frequently enough there won’t be success and then people get discouraged.”
Need for Communication
Hausbeck says she is encouraging landscapers and others purchasing impatiens to work with and develop good relationships with their plant suppliers.
“If a plant supplier doesn’t want to talk to their customers about this disease or any other disease or doesn’t seem to know what the customers are talking about, this should raise a red flag,” she says. “The suppliers should be able to provide details on what they have done to prevent the disease, including their scouting and preventive fungicide program and the specific dates of fungicide applications. If they don’t have the answers to these types of questions, then it might be time to consider another supplier.”
For more information: Bill Calkins, Ball Horticultural Co., email@example.com; www.ballhort.com;  Dave Self, Wyld West Annuals, dave@wyld
westannuals.com; www.wyldwestannuals.com;  Mary Hausbeck, Michigan State University, Department of Plant Pathology, firstname.lastname@example.org.
Although concerned with the impact impatiens downy mildew will have on the production and sale of impatiens walleriana in 2013, growers are planning to offer this crop along with alternative plants.