Talk about making weather work for you. Northwest Horticulture has leveraged its ideal location, plus extensive perennial expertise, to become a major dianthus producer here in the United States.
Each year, Northwest Horticulture plants 15 acres with more than 3,000 dianthus stock plants that produce millions of plugs for fall, winter and early spring sales. Northwest Horticulture’s home in Washington’s Yakima Valley, about 200 miles east of Seattle, offers the ideal climate for perennials production.
Think Washington equals rain? The Yakima Valley is a world away from Seattle’s gloomy, wet climate. Instead, Northwest Horticulture is located in a desert-like climate that receives about seven inches of annual rainfall and more than 320 days of sun.
Northwest Horticulture has a true winter with temperatures that can drop below 0°F, but it sees little snow. In summer, temperatures can be as high as 100°F but they’re balanced by comfortable nights in the 60s.
In fact, the perfect weather bestows another benefit: cleaner plants. The low night temperatures and low humidity levels translate to low disease and insect pressure.
“We have a very definite winter that breaks the cycle of most insect pests,” says Ricardo Campos, general manager of Northwest Horticulture’s Mabton facility, where dianthus are produced. “For example we don’t have a whitefly issue. And because of our low humidity and mild night temperatures, we don’t experience high pressure from foliar diseases such as powdery mildew or alternaria.”
Northwest Horticulture is also fortunate to have plenty of water despite low rainfall. With many nearby Columbia River tributaries fed by snow melt from the Cascade Mountains, irrigation is easy to manage.
“It’s the perfect cultural conditions in temperature, day length and daylight,” says Blair Hoey, new product development and western region sales manager. “We’re in a desert area with the right temperatures for dianthus production, which means the plants go through a true vernalization process. We get very vigorous, strong cuttings.”
Of course, Mother Nature can’t take all the credit. Without the knowledge of people like President Bruce Gibson, whom Campos calls “an encyclopedia of perennials,” Northwest Horticulture’s region is just another hot, dry place.
In 10 years of dianthus production, the Northwest Horticulture team has taken the ideal combination of knowledge and weather and run with it, installing high tech greenhouses and equipment and establishing rigorous production protocols and processes to ensure excellence in every tray.
People, Processes, Protocols
A core group of experts with decades of combined experience has made production a specific science. Stock Manager Michael Ferguson works with a 15-person team dedicated to cultural activities; Head Grower Jorge Alatorre teams with six grower/propagators; and Carla Correa leads the labor department with its nearly 150-person team focused on quality control, harvesting and trimming.
Dianthus production at Northwest Horticulture runs on a carefully regimented schedule. The company now produces more than 50 dianthus varieties in five tray sizes: 200, 162, 128, 72 and 58. Working with breeder partners worldwide (particularly PlantHaven for dianthus), the operation is constantly researching, sourcing, trialing and re-trialing new genetics, plus producing existing varieties.
Production starts with clean stock planted into clean, methyl-bromide treated soil each spring, then continues on a careful schedule.
“We trim on time, fertilize and water carefully,” Campos says. “When cuttings are harvested, we pay special attention to cold chain management.”
All cuttings go into a cooler within 20 minutes of harvest (which peaks from June to September), and they’re kept at 40°F until the plant moves into a clean greenhouse. After sticking, plants spend 10 days in high humidity stage one conditions to initiate roots. Next, they move into lower humidity conditions and higher light for four weeks to complete the rooting process and quickly initiate basal shoots. They finish in high light and outdoor conditions to properly prepare them for planting and shipping.
Northwest Horticulture cuttings are pre-trimmed to allow for immediate planting when appropriate. The operation follows a precise schedule for trimming to ensure maximum performance.
“It’s our goal to ship plants ready to go into the final container with the least amount of work for our customers.” Hoey says. “You’ll have plants that burst with top and bottom growth following transplanting. You do not have to wait for them to adapt to outdoor conditions.”
Workers must clean hands and tools with alcohol regularly, after handling only a few trays. Cuttings are produced in a restricted area of the greenhouse not accessible to the general population.
“It’s all about people, processes and experience,” Hoey says. “We have a series of processes in place that are carefully managed by professionals who ensure the cleanest, highest quality production.”
Northwest even takes quality management as far as one-by-one inspection. “Every tray that goes out the door is hand inspected,” Campos says. “We have a dedicated sorting group that’s driven by quality standards.”
All cuttings must meet Northwest Horticulture’s exacting criteria for uniformity across the tray. “Roots go all the way to the bottom of the tray, and growers will see a plug that is ready to expand,” Campos says.
Equipment, Efficiency, Excellence
Northwest Horticulture produces its dianthus at its high-tech facility in Mabton, Wash. (A second location in Mt. Vernon, Wash., also produces perennials and propagation material.) Of the 300 total acres at Mabton, 14 are under cover and 30 acres are dedicated to outside container fields, with the balance of the 255 acres used for field-grown roses and sedums.
An 8-acre MX glass greenhouse with rolling benches provides an optimum environment for young dianthus plant production. The 6-acre open-roof Cravo is ideal for toning and climatizing.
A year ago, Northwest Horticulture added Svensson heating curtains over the 8-acre structure, making a significant difference in heating costs. “We’ve cut our energy costs by 25 percent,” Campos says. “We’re not just reducing temperatures but seeing more uniformity of temperatures in the greenhouse.”
“Our cuttings spend 50 percent of their life outside,” Hoey says, “so they’re strong, robust plants, and there’s no acclimation needed.”
It’s a system Northwest Horticulture can say works with certainty–from start to finish.
“We’re one of our biggest customers,” Campos says. “Because we produce from unrooted cuttings to rooted plug to final product in containers, we have the opportunity to see exactly how the processes work at every stage.”