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Roses from the Far North

Len Busch Roses: Competitive through energy savings

The temperature is a chilly 35 degrees Fahrenheit, but the fragrance is intoxicating. Orlando, Chantelle and Rosita Vendela varieties give it their all. Here in the cold storage at Len Busch Roses in Plymouth, Minnesota, roses are waiting to be transported to customers. Minnesota is perhaps the last place you'd expect to grow roses, not being exactly famous for its moderate climate - on the contrary, after Alaska it is the second coldest state in the USA. And although potted plants and cut flowers now account for two thirds of production at this operation that used to specialize in growing roses, roses remain the star attraction. Len Busch Roses is the only large-scale rose grower in the USA outside of California, a position the company fully intends to keep. "Our strengths are quality and freshness," says Managing Director Patrick Busch. That is obviously the right strategy, for the rose grower from the far north is asserting himself with success against the competition. This comes not just from sunny California, but increasingly from South America: "We have been observing this development for about 15 years."

Although the South American roses can have larger heads and usually come at a cheaper price, customers still remain faithful to the longer lasting domestic product with vibrant clean foliage and more fragrance.For one reason, this is due to the quality ensured by short transport routes. The flowers are sold within a radius of 300 miles, which means they are still fresh on arrival at florists' stores and therefore keep well. On the other hand, Busch can also offer competitive prices due to the energy savings he achieves by using PLEXIGLAS® high impact acrylic double-skinned sheet. Since 1981, all the greenhouses at Len Busch Roses have been glazed with PELXIGLAS® sheet, now covering a total area of 15 acres or 500,000 square feet. The material offers significant savings as compared with glass: "We have halved our energy costs," Busch says.

The savings are due to the material's heat-insulating properties. A double-skinned sheet consists of two skins connected top and bottom by a number of ribs. The resulting air cavities act as an insulating layer, because the static air in the cavities is a poor heat conductor as compared with solid material. The co-efficient heat transfer index, or U-value, states how effective this insulation is. The lower the U-value, the better the heat insulation. 16 mm PLEXIGLAS® double-skinned  sheets have a particularly low U-value of 0.49 (BTU/h/f²/°F). In comparison, single glass glazing has a U-value of 1.3(BTU/h/f²/°F),  more than twice as high.Patrick Busch sees further benefits: "The material requires very little maintenance and is resistant to hail. That is very important in this region with its frequent hailstorms."

The light transmission is another vital factor and was a further criterion for using PLEXIGLAS® acrylic sheet. "Roses more than many other flowers need plenty of light for optimum growth, but tulips, gerbera and lilies also flourish in bright conditions.“ According to a gardener’s rule, one percent more light means one percent more growth. That is why glazing should have a light transmission of at least 85 percent. PLEXIGLAS® high impact acrylic sheet transmits 86 percent of direct light, roughly the same percentage as single glazing.

The guiding principle at Len Busch Roses has always been to offer customers the best possible product, and innovations have always driven the company's success. Patrick's father, Len, was known for his creativity, and never stopped looking for innovative ways to cut costs and boost productivity. In 1974, he installed a wood-fired boiler that provided hot water to heat the greenhouses. In 1984, he was one of the first to computerize his greenhouse operation.   Four generations of Energy Conservation His heirs in the fourth generation have maintained this tradition.
Although the heating system has been thoroughly modernized, it is still based on the principle of heating water with a wood-fired boiler – an environmentally friendly method because it uses local wood scrap. This makes Busch largely independent of oil and gas prices. He believes this system, combined with PLEXIGLAS®, equips him to face the future with confidence: "We can plan our costs in advance, not just for supplying our greenhouses with energy. With PLEXIGLAS® sheet, we have opted for a material that is sustainable because of its long service life and does not need to be replaced, unlike other materials." So the fifth generation at Len Busch Roses also stands a good chance of continuing to supply customers with the queen of flowers, home-grown in Minnesota. 

The story about the queen of pot plants is just one of the articles in the current issue of the Greenhouse Journal: PROFITABLE GROWTH UNDER ACRYLIC. Download PDF  

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