A History of Minnesota Floriculture

Development of new and improved floricultural cultivars continued. F-1 hybrids were grown in greater numbers each year. New cultivars of geraniums, cyclamen, impatiens, geraniums, roses and many other plants were developed and released by public and commercial plant breeders. There was a constant effort to uncover new and novel cut flower and pot plant species. Greater use of plant tissue cultures for plant propagation and for inducing potentially desirable mutations was anticipated.

Insect and disease control remained a constant challenge. Even as efforts to develop resistant cultivars and learn more about the use and effectiveness of natural predators were expanding, government approval of new pest control products was becoming more costly and difficult to obtain. Research findings with floricultural crops emphasized the desirability of more efficient, precise environmental crop production control. Computerized control improvements were coming into use, and further refinements were anticipated.

Increasing imports of cut flowers from low-wage nations, stricter government regulations on domestic producers, including more required documentation and paper work relating to chemical use and disposal, etc., all put additional pressure on domestic producers. Computers facilitated better monitoring of business and production records, and many Minnesota commercial flower growers adjusted their operations to overcome the challenges. Mechanization and automation were important tools used to facilitate their efforts.

Federal and state funding of university research, agricultural extension and teaching were failing to keep pace with inflation. Floricultural research was often defined as having lower priorities for funds, and many horticultural research and development budgets were cut in the 1980s. Researchers were forced to spend significant portions of their time seeking grant money from non-government sources to supplement their depleted budgets.

The potential sources of private funding for horticultural research stretched across the floral industry. They included state florists groups, industry organizations such as the American Florists Endowment, the Bedding Plants Foundation, the Fred C. Gloeckner Foundation, Paul Ecke Poinsettias, Roses, Inc., and the Ohio Floriculture Foundation. Support was also solicited from and provided by some of the larger greenhouse supply and chemical companies. The University of Minnesota floriculture staff was fortunate to be able to obtain a progressively increasing number of grants to partially offset the leaner budget allocations from the University.

Many American university floricultural faculty members were of the G.I. Bill funded generation of college students. They earned their graduate degrees in the decade following World War II. Many of them were, therefore, reaching retirement in the 1980s, and because of the University's financial woes, some of the vacated positions were eliminated or reclassified from floriculture to other interests. Minnesota lost the horticultural extension specialist position that had been held by Dave Koranski, but was fortunate to be able to partly replace it with a technical assistant position in extension horticulture.

Extension budgets, including travel funds, were lowered significantly. The result was that greenhouse visits and one-on-one contacts on greenhouse sites were significantly curtailed. Mark Ascerno of Entomology and Frank Pfleger of Plant Pathology continued to be productive colleagues, and continued their frequent contributions to the Minnesota State Florists' Bulletin.

Industry Developments

Mark Swart, who started Valley Floral nursery in Winona in 1977, constructed a 35,000 square foot greenhouse range in 1980. Next, he purchased the West End Greenhouse firm, closed the greenhouses and maintained the retail business.

The original Lyndale Fruit and Vegetable Market burned to the ground in December 1980. A large replacement opened for business in April 1981. Palmer Siegel died in 1985, and Tim Duoos bought the firm in 1986, renaming it Lyndale Garden Center. Duoos and company president Dick Dwyer initiated ambitious retail expansion, opening a second garden center with greenhouses in Burnsville in 1989. This was followed by centers in Fridley (1992) and New Hope (1993). Their Gardener's Paradise center opened in the Mall of America in 1994 with an indoor greenhouse. It was the largest locally owned store in that Bloomington 'megamall.'

John Dramm, of Chicago area flower wholesaler Koehler and Dramm, bought the Minneapolis branch of Amlings in 1976. His son Rich, who managed the branch, purchased the business in 1981. He built the business into a large operation and added prepared mixed bouquets for wholesaling, an Institute of Floristry (1988) and other innovative features. The business occupied two acres of indoor floor space.

Tom Heiserer, the son of Lakeland Florist Supply, Inc., owner Bill Heiserer, became the owner in 1982. He moved the firm to Edina in 1983 and has continued to operate the business up to the present.

The largest nursery in the upper midwest, J.V. Bailey Nursery of Newport, started building greenhouses in 1982. The business had started as a fruit and vegetable production establishment in 1907, expanding into the nursery field soon thereafter. Since 1957, the business has been wholesale only. By 1995 there were 11.5 acres of plastic film covered greenhouses. More than eight acres were devoted to bedding plants, with the rest used for perennial plant production, plus propagation of deciduous and evergreen cuttings in the fall, and evergreen cuttings in the winter. Third generation Rod and Gordon Bailey Jr. operate the business, with eight fourth-generation family members employed in the nursery. Don Sellinger, not a family member, heads the firm's floricultural division. Annual production includes 150,000 flats of bedding plants, 30,000 flats of perennials and 18,000 hanging baskets.

Bailey Nursery invested heavily in mechanical aids and greenhouse automation. Its equipment includes roll-out benches, retractable heat and shade curtains, mechanical seeders, computer controlled traveling boom irrigation systems and seed germination chambers. Bailey invested $100,000 in a bedding plant transplanter and attachments for the 1995 season.

Students Erect Greenhouse

Students gained practical greenhouse construction experience in 1979-80, erecting a donated greenhouse they dismantled and moved from an off-campus location. The unit's availability enabled students to gain additional experience in growing floral crops. (Photo by author)

Hermes Floral gave the University of Minnesota a standing 30 x 130 foot steel frame aluminum greenhouse in 1979. It was disassembled, moved to the St. Paul Campus and erected by student volunteers and students in class laboratory sections. Greenhouse builder Albert J. Lauer contributed technical assistance. Norm Polzin, research plot coordinator, and Dick Widmer supervised the students reconstruction work. Commercial flower growers and suppliers provided funds and supplies needed for the project's completion. The University provided the utility connections. The facility was dedicated in 1982 and has been providing students with practical experience in growing floricultural crops.

In 1980-1981, Hermes erected more greenhouses at Becker. By 1983, the firm had also finished combining all of the Becker greenhouses heated with warm water, including those built by other firms and the experimental unit, into one complex. Visitors from around the nation, and from countries as far away as New Zealand, came to examine and inspect the facility. The primary crop at Becker was roses, along with some less common flowers.

Hermes' wholesale cut-flower unit in Falcon Heights was expanded in 1985. In 1988, the supply department was enlarged. Crops at the Larpenteur Avenue site were primarily potted plants for the retail business, with some sold wholesale. The Roseville Greenhouses were sold for land development in 1989. New greenhouses were erected in Hudson, Wisconsin, in the same year.

Farmers' Markets Thrive

A new St. Paul Farmers' Market opened at 5th and Broadway on May 1, 1982. It has thrived with a varied selection of vendors offering floricultural crops, in addition to the usual farmers' market array of fruits and vegetables.

In both the Minneapolis and St. Paul markets, the sale of greenhouse grown plants occurred primarily in the spring before outdoor crops were available. Summer and fall sales of floricultural crops were primarily potted plants and cut flowers, both indoor and outdoor grown. Some vendors also resold items produced outside of Minnesota. Crafts produced by Asian immigrants of several nationalities have also been offered for sale there.

More Industry Developments

Richard Wagner, the third generation of his family to operate their business, and his sons Ronald, a University of Minnesota floriculture graduate, and Scott added new greenhouses to their Minneapolis range and became geranium specialists in the 1970s and 1980s. They also expanded their facilities by purchasing the adjacent Cornelius greenhouse range in 1982, which they subsequently connected to the existing Wagner range to enable them to be operated as a single unit. They started germinating seeds and growing seedlings in plugs in 1980, and also added poinsettias to their product line. The whole range was gradually rebuilt in accordance with a long-range modernization plan developed by the company. Ronald's cousin, Russ Wright, joined the Wagner firm to direct the firm's computer controls and programming.

A group of 13 Minnesota growers toured Denmark in the summer of 1983 to visit some of the outstanding floricultural enterprises. Harold Wilkins planned the trip, and Dick Widmer accompanied the group. Enterprising growers, supply firm and sales representatives also visited Europe individually to examine new ideas and growing methods being pioneered there.

Terry Crombie established Poly Tex, Inc., in Castle Rock in 1983 to develop and sell new and helpful products and structures for the greenhouse industry. A major item brought to market in 1986 was the portable, plastic film covered 'garden mart' greenhouse designed for spring retail sales use. Other products include plastic heat blankets, collapsible plastic tube greenhouse vents, and greenhouses designed for maximum natural ventilation. Sons Brian and Michael also work for the firm.

In 1984, Brian Anderson started operating the old New Ulm Greenhouses under the name New Ulm Growers 99 years after the firm was founded. Brian now owns the whole unit and specializes in plants for his retail store.

A tornado which touched down in St. Anthony Village in April 1984 destroyed the home base greenhouse range of John R. Johnson. It also decimated the greenhouse facilities of the adjacent Hertog Floral Inc. The Johnson facility had been expanded over many years. Instead of rebuilding, both firms sold their land for redevelopment. In 1987, a new range called Everton Growers was started in Hugo by the John R. Johnson firm. Hertog Floral Inc., ceased doing business.

Ambergate Gardens was opened in Waconia in 1985 by Mike Haeger. He had been a landscape gardener at the University of Minnesota Landscape Arboretum, and was a University graduate with a major in foreign languages. His perennial business has grown significantly with the increased popularity of perennials in recent years. Haeger is active in the Perennial Plant Association.

In 1986, the Minnesota Commercial Flower Growers and the J.R. Johnson Research Fund arranged for the preparation of a packet of video tapes, an employee training manual, booklets and forms to legally inform and protect owners and employees working with and around pesticides. This was done to help owners and employees conform with Minnesota's 'Right to Know' law. The Safe Handling of Pesticides packet was sold nationwide, with profits going to the J.R. Johnson Research Fund.

Roses Inc. held a 'Growers School' in Bloomington in October 1986.

Bachman's turns 100 Years Old

The Bachman firm celebrated its 100th birthday in 1985. At that time, the Society of American Florists coordinated the Christmas floral decoration of the White House in Washington, D.C. As part of the commemoration of its centennial year, the firm contributed a custom-made metal stand that held 160 poinsettia plants, stood 12 feet high and was shaped like a Christmas tree. Alan Bachman himself set up the poinsettia 'tree' in Washington. The White House was so pleased that they ordered a second tree complete with plants a few days later.

The White House tradition continued with Bachman's poinsettias through the Reagan administration. The poinsettia 'tree' stands were not used after Reagan left office, but the poinsettia plants used for decorating public areas of the White House continue to be Minnesota-grown and purchased from Bachman's.

By 1985, Bachman's was operating 15 retail stores in the Twin Cities metropolitan area, and one more in Rochester. There were also 48 European Flower Market shops in Minnesota, 12 acres of greenhouses, a 438-acre nursery, a garden and landscaping division, a commercial interior landscaping division, a wholesale nursery center, a commercial floral sales unit and Department 56, the wholesale gift subsidiary.

With 1,200 employees, Bachman's had grown to be one of the world's largest florist and nursery operations. Sales were in excess of $50 million annually. During the winter holidays, Bachman's made up to 14,000 floral deliveries per week, with a fleet of 23 floral delivery trucks owned by the firm, and numerous others leased for the busy holiday season. When Stanley retired as president in 1987, Lloyd's son Todd, a floriculture graduate of the University of Minnesota, became president of the company.

Other Centennials

Professor William H. Alderman, living in California, reached 100 years of age in 1985. The University's Department of Horticultural Science and Landscape Architecture sent their former chief an arrangement of 100 red sweetheart roses to celebrate his centennial birthday. He died a few days later.

One hundred years after 'Fred' Busch started building greenhouses in 1885, in what is now south Minneapolis, third generation Frederick and his sons Carl and Fred built modern greenhouses in Rogers. They had worked at the Busch Brothers range in Golden Valley until it was sold for land development in 1984. Their primary crops in the new range were seasonal pot plants. They also grew and purchased some cut flowers for wholesaling.

Florist Products and Wholesale Prices

Floricultural product prices continued to increase along with those of most other products. This wholesale price trend was confirmed in surveys conducted by the University of Minnesota for the years 1979 and 1986. (Table 1)

Minnesota Distributing and Manufacturing, Inc., was started in Minneapolis in 1987 by Steve Grabski and Dave Rogowski, former employees of J.R. Johnson Supply. Their product line offered greenhouses, growing benches and growers supplies.

The Landscape Alternatives company was founded in 1987 by Karl Ruser and Ray Robison. Ruser earned a master of science degree and worked as an assistant scientist in horticulture at the University of Minnesota before starting the firm. Robison received his undergraduate degree from the Department of Horticultural Science. Landscape Alternatives has been a wholesale and retail seller of native prairie wildflower plants and grasses. Their business, which utilizes greenhouses, has been increasing.

Industry Development in the Decade

The leadership of Bedding Plants, Inc., recognized the need for a national organization to represent all growers of floral products. In 1988, the organization enlarged its objectives and became the Professional Plant Growers Association. The research funding unit remained the Bedding Plants Foundation, Inc.

Stanley Bachman was inducted into the SAF Hall of Fame in 1989 for outstanding contributions to floriculture. Clare DaRe also replaced Jim and Gen McCarthy as executive director of the North Central Florists' Association that year.

Across the nation, in the 28 states where floricultural production was considered to be a major industry, both the numbers of different floricultural crops and the total volume of sales of those crops continued to increase annually through the 1980s. The USDA tracking of the floriculture industry showed the number of crops increasing from 17 to 28 across the decade, and the total value of those crops growing from $921 million to nearly $2.77 billion by 1990, an increase of about 300 percent. Minnesota production increases nearly kept pace, growing from $15.8 million in 1980 to almost $42 million by 1990, an increase of 265 percent. (Table 2)

Although total cut-flower production sales value significantly increased both nationally and in Minnesota from 1980 to 1990, their percent of market share held by cut flowers decreased appreciably. The possible causes were many, including significant increases of cut-flower imports from South America, and greater increases in domestic production of potted and bedding plants. Dollar volume of potted plant and bedding plant sales increased at least 400 percent in the 28 states and about 300 percent in Minnesota.

Pot plant production sales in 1990 exceeded domestically grown cut-flower sales in all 28 floricultural production states, not just in northern states such as Minnesota. Bedding plants sales represented 55.8 percent of total wholesale floriculture production sales for Minnesota, compared to 35 percent for the 28 state totals. Even in 1980, Minnesota and other northern states signaled their regional bedding plant surge with 44.7 percent of their wholesale floricultural production in bedding plant sales, versus 23.3 percent for the 28 states combined. Minnesota-grown foliage plant production sales were fairly stable, showing a return to average conditions following the unusually high demand for this crop in the 1970s.

Use of High Intensity Lighting

A rose house showing the rows of high-pressure, high-discharge sodium vapor lamp fixtures overhead. They were used to improve quality and increase yield of cut flowers, especially in the short-day half of the year. (Photo by author)   An indoor section of a garden center prior to the outdoor growing season showing potted cinerarias, recently planted packs of annuals, pots of perennials and hanging baskets plus a few spruce trees.

Use of supplemental lighting, especially high-pressure sodium lamps, to improve and accelerate plant growth primarily in the short- day season became relatively widespread in the north in the 1980s. Crops that benefitted from this treatment included chrysanthemum stock and potted plants, plugs of many species, gerbera, gloxinias and rose cut flowers.

Energy prices moderated from their peaks in the previous decade. Probably of equal importance was that many greenhouses were now better maintained and more efficiently operated to limit heat loss.

Plastic Greenhouses

The 1990 USDA Floricultural Crops Summary disclosed that Minnesota had 244 floricultural production establishments with $10,000 or more in gross sales, and that there were almost 7.2 million square feet of greenhouses in the state. They were glazed with a variety of materials: glass, 1.07 million square feet (15 percent); rigid plastics, 1.59 million square feet (22 percent); and film plastics, 4.54 million square feet (63 percent).

The rigid plastics included the now less popular fiberglass reinforced plastics as well as the newer box-ribbed, double layer plastics which are long lasting, heat conserving, break resistant and higher priced than glass. Minnesota appeared to be ahead of the national trend to plastic film covering, in terms of the percentage of greenhouse area under that material.

The lower priced plastic film structures which are widely used for, but not limited to, bedding plant production fueled a healthy increase across the industry in greenhouse area. Nationally, in 1990 there were 404 million square feet of covered greenhouses, plus 313 million square feet of shade and temporary cover growing area. There were also another 26,188 acres of open ground production area devoted to floriculture. Types of glazing materials used by the 9,185 nationally surveyed growers were glass (20 percent), rigid plastic (24 percent) and plastic films (56 percent).

Safety Standards

Government agencies established strict standards prior to 1980 for the safety of greenhouse workers and others who might be in the vicinity, as well as for protection of the environment. Development of the standards continued, but enforcement was softened during the terms of presidents Reagan and Bush (1980 to 1992). In the 1990s, tests of soil beneath greenhouses for toxic substances were frequently required, along with the removal of undesirable residues, before bankers would provide financing for the purchase of greenhouses.

Industry Associated Activity

An outdoor garden center in late summer featuring potted garden chrysanthemums in bud and in bloom, ornamental kale, blooming garden lilies and more. (Photo courtesy Bachman's)

The Minnesota Commercial Flower Growers continued to hold monthly information meetings. Its functions included serving as the growers' contact and support group when dealing with the University of Minnesota, government agencies, and other groups and organizations that might effect its members. It also organized educational tours to growers, conservatories, experiment stations, and similar facilities in other states and nations. From it inception in 1953, this relationship between the University and the state's growers remained beneficial to both parties.

The North Central Florists' Association continued to stage attractive displays at the Minnesota Sate Fair, as it has through the century. Amateur designers and flower growers have sought awards there annually in a wide array of staged categories.

Minnesota has been fortunate in that sales representatives of local and out-of-state florist and greenhouse supply firms, who called on Minnesota growers one or more times annually, were usually high caliber, well-informed individuals. They have frequently served as trouble shooters, and offered the latest information on their products in addition to soliciting orders.

Additional advice and assistance to the industry's practitioners has come from a number of local supply firms and specialty growers, and from a few large out-of-town firms regularly sponsoring trade fairs, exhibits, short courses, etc., for growers and retail florists. This private industry assistance has supplemented, but not replaced, the needed, timely assistance received from regular Minnesota Agricultural Experiment Station and Minnesota Extension Service specialists.

University Faculty Activity

Jimmy Ozburn, Ph.D., left the University of Minnesota to accept an administrative position at Kansas State University in 1981. Jane McKinnon served as the Department's interim head until James Bartz, Ph.D., became the sixth head of the unit in 1982. Ozburn later became president of North Dakota State University, Fargo.

Dick Widmer was awarded the SAF Alex Laurie Award for Research and Education, and became a Fellow of the American Society for Horticultural Science in 1981. He also served as a Senior Research Fellow at the Levin Horticultural Research Center in New Zealand for 10 months in 1980-1981. His sabbatic leave objectives were to evaluate various growth media nutrient analysis methods, study interpretation of analysis results and determine preferable media nutrition levels for specific crops. Thereafter, he visited various research establishments and commercial flower growers in Australia and Europe before returning to Minnesota.

David Koranski left the Department for a position at Iowa State University in 1982. Graduate student Nancy Olson was hired as a part-time liaison between commercial growers and extension specialists on the St. Paul Campus.

Harold Wilkins was elected a Fellow of the American Society for Horticultural Science in 1984. He spent a six-month leave at the Royal Agricultural University of Norway in 1987, investigating the effects of twilight and of red, far-red and blue light on plant growth.

In 1985, the University of Minnesota hosted the Intercollegiate Flower Judging Contest for the second time on the St. Paul Campus. Local growers and wholesalers were fully cooperative in donating plant materials and participating in educational sessions. Pi Alpha Xi initiated Stanley F. Bachman and John R. Johnson as national honorary members during their meeting. Both men had long, innovative, productive careers in the floriculture industry, and were highly worthy of the honor. T. Ferris, Ph.D., of the University of Wisconsin at River Falls co-hosted the contest. Dick Widmer chaired the local committee and Harold Wilkins assisted. The American Florists Endowment, Paul Ecke Poinsettias and the national Pi Alpha Xi fraternity contributed the awards for student and team winners. Seventeen colleges entered teams in the contest. The Ohio State University team won first place followed by Cal Poly State University and New Mexico State University in that order.

Dorothy Johnson became Executive Director of the Minnesota State Horticultural Society in 1987.

Widmer and Wilkins Leave the University

Dick Widmer retired from the University on July 31, 1988, after 39 years of service.

Harold Wilkins was inducted into the SAF Hall of Fame in 1988 for outstanding service to floriculture. He resigned from his professorship at the University on December 31, 1988, after 221/2 years of service, and became the Technical Director of a large California flower and plant production company. Harold received numerous additional awards, including being named a Pi Alpha Xi Fellow in 1993.

New University Floriculture Faculty

Floriculture faculty John Erwin (left) and Mark Strefeler were hired in 1989 to fill the vacancies left by Dick Widmer's retirement and Harold Wilkins' resignation from the University of Minnesota. (Photo courtesy Mark Strefeler)

New faculty members, John Erwin and Mark Strefeler, were hired in the second half of 1989 to fill the University vacancies created by Dick Widmer's retirement and Harold Wilkins' resignation. Erwin was hired to conduct research in floricultural physiology and to head the floricultural extension program. He earned his Ph.D. studying under Royal Heins at Michigan State University. Heins, in turn, had earned his doctorate as a graduate student under Wilkins at the University of Minnesota.

Strefeler, a plant breeder and geneticist, earned his Ph.D. at Cornell University. He was hired to work on cultivar improvement and genetics of varied floral crops, and to teach floricultural courses, which had been reduced in number because of the Widmer and Wilkins vacancies.

The University instituted charges for some laboratory analytical services, including plant tissue (foliar) analysis in the late 1980s. The charge for soil analysis was also increased. John Erwin increased the size of the Minnesota State Florists' Bulletin. Dues of the Minnesota Commercial Flower Growers, which in part paid for bulletin printing and mailing, were increased. In recent years, the bulletin has been distributed to member florists only.

University Floricultural Research Findings

Results of research by faculty and staff of the University of Minnesota continued apace through the 1980s. Even a brief compilation is of substantial length.

Alstromeria

Alstromeria will bloom after treatment at 40 degrees Fahreheit for two to six weeks, continuing to bloom until soil warms above 60 degrees. Vernalization of the cultivar 'Regina' was provided by six to eight weeks at 40 degrees or 16 weeks at 55 degrees. After four to six weeks at 40 degrees, plants flowered sooner at a forcing temperature of 65 degrees versus 55 degrees. A 13-hour photoperiod provided by day extension or night interruption hastened flowering.

Total shoot production during the flowering span was inversely related to duration up to eight weeks of treatment at 40 degrees. Total shoot and flower shoot production were not influenced by the number of weeks at 40 degrees when grown at 70 degrees if clumps were divided prior to treatment.

Alstromeria require frequent fertilization for best growth and they prefer nitrate-nitrogen with a one-to-one ratio of nitrogen to potassium.

Azaleas

Greenhouse azaleas were studied to find ways to replace the expensive low temperature requirement, shorten production time and facilitate earlier forcing into bloom. Substituting GA3 (gibberellic acid) spray for low temperature was promising, but variable. A combination of GA3 and a shortened low temperature treatment was effective. A night interruption, long day photoperiod should follow low temperature or GA3 treatment until flowering. High light intensity increased GA3 treatment effectiveness.

Calla Lilies

Yellow, Zantedeschia elliottiana, and pink, Z. rehmannii, calla lilies held at 50 degrees Fahrenheit until planted and grown as potted plants flowered in 62 and 52 days, respectively, when forced at a constant 68 degrees. They required up to 110 days when forced at lower temperatures. Rhizomes replanted immediately after mechanical leaf removal with no storage period did not grow. Rhizomes replanted after leaf senescence induced by withholding water sprouted without storage, but height, leaf number and shoots per rhizome were greater from rhizomes that were stored three weeks at 50 degrees. Height and number of leaves and shoots were greater after storage at 48 degrees than at 39 degrees or 72 degrees. Z. rehmannii growth with a medium temperature of 68 degrees or 72 degrees and air temperature of 59 degrees or 68 degrees accelerated flowering compared to a 59 degree air and ambient medium temperature. Flower numbers at all temperatures were the same over a 120-day cycle.

Plants grown with a night interruption in the first cycle, and then replanted and grown for a second cycle, were taller than plants grown from short day first-cycle plants. Flowering was not altered. Lowering natural irradiance up to 85 percent did not alter flowering time or number. A preplanting rhizome soak in GA3 provided earlier flower bud initiation, and increased numbers of flowering shoots and flowers per shoot.

Carnations

A sequence of 30 natural days, 75 short days and 30 natural days until flower harvest increased production 75 percent over the natural day controls when cuttings were planted in June and discarded in March.

Chrysanthemums

Ten new garden chrysanthemum cultivars were introduced in the 1980s (Appendix B). Significant progress was made in developing seed propagated lines, though none were as yet ready for release. A day-neutral cultivar was developed that bloomed on attractive plants when grown in continuous light at a constant 83 degrees Fahrenheit.

Inheritance of flower color and analysis of flower color phenotypes with thin-layer chromatography were researched. Flower color inheritance was studied using clonal testers. Cultural requirements and schedules for pot plant production of new and appropriate University of Minnesota cultivars in 3-inch to 8-inch pots were updated.

Cyclamen

Cyclamen seed germination in a sphagnum moss peat medium occurred at a pH as low as 4.5, but a pH of 5.0 to 6.8 was preferable. A calcium level of 20-25 parts per million, when combined with other nutrients was especially beneficial in early growth. Plant growth in a 50 degree or 60 degree Fahrenheit air temperature with a 66 to 70 degree root temperature for 60 days, starting 90 days after the seed was sown, was equivalent to that of plants grown at a constant 66 degree to 70 degree air temperature and resulted in energy savings.

Capillary mat watering of cyclamen was successful. Vegetative characteristics were significantly affected by rate of application and balance of nitrogen and potassium. Chloride and sulfate sources of potassium were equally effective. Flowering was delayed by inadequate, excessive or unbalanced fertilization.

Leaf blades of the first 17 leaves grew at about the same rate, except for leaves 6 and 7, which grew significantly faster. Growth rate of successive leaf blades after leaf 17 almost tripled. Although the first flower buds initiated in the axils of the sixth and successive leaves, flowering usually did not occur until plants unfolded 35 or more leaves. A spray application of 10 parts per million GA3 to the crown of plants with 10-20 unfolded leaves accelerated flowering by two to five weeks and provided more uniform flowering. Applying GA3 also accelerated leaf unfolding. Revised schedules were developed for producing flowering 4-inch to 6-inch pot plant specimens in seven to nine months.

Lilies

'Nellie White' Easter lily leaf unfolding before visible flower buds ranged from 0.7 per day at a constant 40 degrees Fahrenheit, to a maximum of 2.5 per day at 80 degrees. Maximum flower bud development rate once flower buds were visible was at a constant or a 24-hour average 70 degrees. Higher temperatures did not accelerate flower bud development, but resulted in taller plants. Peak flower count developed at 55 degrees. 'Nellie White' plants with white puffy buds were stored up to 26 days with no loss in plant quality. They were held at 35 degrees with 10-footcandles of light and moist soil.

The annually revised guidelines for handling and producing quality potted Easter lilies were published on a national basis. Evaluations of hybrid colored lilies and cultural requirements for Minnesota pot plant production were also prepared, based on greenhouse studies.

Moss Peat Media

Appropriate nutrient formulas were developed for addition to sphagnum moss peat media used for propagation and production of varied florist crops.

Picloram (Tordon)

Red and Blue 'Flash' cultivar petunias showed flower distortion from as little as four to six irrigations of water containing 0.45 to 3.6 parts per billion of the herbicide picloram within 18 days of the first application. Tomato cultivar 'Sunny' exhibited symptoms after 21 days. 'Novette Pink' impatiens were more resistant. Reaction to such a low concentration has been considered very unusual.

Plugs

Guidelines were developed for plug culture.

Poinsettia

Best response to first pinches of young poinsettia stock plants potted March 15, April 15 and May 15 resulted when leaving seven, nine and eleven nodes respectively. Thereafter, best plant response followed leaving 2 to 4 nodes when pinching or taking cuttings. A constant 70 degrees Fahrenheit resulted in the quickest production of high quality cuttings of 'Annette Hegg Brilliant Diamond', 'Annette Hegg Lady' and 'Glory' ('Gutbier V-14') selections. Optimum temperature range for flower bud initiation was between 65 degrees and 70 degrees, with a constant 65 degrees preferable. A short photoperiod hastened bract development between 60 degrees and 75 degrees. Foliar applications of calcium lessened leaf-edge burn, but soil applications of calcium were ineffective. Attempts were made to determine if a 'free branching' agent was present in poinsettias. New cultivar trials were conducted.

Roses

Stem length of 'Forever Yours' hybrid tea roses decreased as the level of potassium fertilization increased. Foliar calcium levels were positively correlated to flower bud weight. Flower buds on plants top-dressed with gypsum were longer at all stages, than buds on plants that were not top-dressed.

University Developments

Unveiling of the plaque at the student restructured teaching greenhouse dedication ceremony in 1982. Pictured are Paul Olson of Minneapolis Floral (left) and John Hertog of Hertog Floral (right). (Photo by author)

The student population pursuing graduate degrees in the Department of Horticultural Science and Landscape Architecture peaked at about 100 in the 1980s. Graduate student numbers in the floriculture program peaked at about 11 at any given time. Not all of these students received grants or assistantships.

The Care of House Plants, Minnesota Agricultural Extension Service Bulletin 274 written by Dick Widmer in 1953, proved to be one of the most popular extension bulletins ever in Minnesota. It was revised in 1961, 1970 and 1982, increasing in size from 32 to 64 pages over those revisions. The bulletin was distributed as a North Central Region Extension Bulletin. An estimated 350,000 copies have been distributed.

Greenhouse Advancement, Mechanization and Automation

New systems, products and methods have been developed and applied across the industry, primarily within the last 30 years and especially in Europe and America (see summary list below). These advances, ranging from improved greenhouse construction to new plant growing techniques, clearly demonstrate that the floral industry has awakened from the relative slump in recent decades that generally paralleled the nation's economic woes.

Growing Structures

• Metal framework for all styles
• Improved life-span polyethylene films
• Use of tempered glass in commercial greenhouses
• Glass now the least used glazing
• Greater use of rigid, box rib, two-layer rigid plastic glazing as well as plastic films

Benches

• Rolling bench tops to minimize aisle space
• Bench top trays for growing and moving plants
• Hanging baskets on movable belt lines that are watered, fertilized and sprayed as they pass the work station
• Roll out bench top trays to move plants in and out of greenhouse, depending on the weather, or to the headhouse
• Conveyor belts and tracks with computer controlled destinations
• Special greenhouse carts

Growth Media

• Soilless plant media
• Nutrient film technique
• Machine blenders, mixers
• Rock wool

Plugs

• Containers machine filled with growth medium
• Environmentally controlled growth chambers for seed germination
• Machine seeding, with or without plugs
• Machine labeling of pots and packs

Irrigation

• Intermittent mist
• Nozzle watering
• Automated overhead booms
• Ebb and flow (injection)
• Tube watering
• Irrigation mats
• Troughs

Fertilizer

• Controlled-release, non-organic products
• Wide use of liquid application
• Proportioners and injectors
• Supplemental atmospheric carbon dioxide
• Monitors in line beyond injectors for checking concentration
• Microelement emphasis, especially in soilless media
• Monitors for adjusting liquid and nutrient levels in nutrient solutions in holding tanks

Temperature Controls

• Natural gas as the most widely used fuel
• Power plant waste heat as source of heat
• Bench bottom hot water tube heating
• Thermal curtains for night use
• Fan-jets for air circulation and temperature uniformity
• Evaporative pad cooling
• Warm night, cool day plant height control technique (DIF)
• Automated waste wood furnaces, where wood supply is reliable
• Fin heating pipe - aluminum and copper
• Horizontal air flow
• Collapsible polyethylene tube vents
• Honeycomb paper evaporative pads

Light

• High-intensity (fluorescent, mercury, sodium vapor) lamps for plant illumination in short-day portion of the year
• Automated photoperiod and light intensity control curtains

Computer Controls

• Available for almost all greenhouse operations and procedures, including most of the items noted in the eight sections above, and for lowering and raising humidity and injecting carbon dioxide into greenhouses, and growth and storage chambers.

Produced by Communication and Educational Technology Services, University of Minnesota Extension.

In accordance with the Americans with Disabilities Act, this material is available in alternative formats upon request. Please contact your University of Minnesota Extension office or the Distribution Center at (800) 876-8636.

University of Minnesota Extension is committed to the policy that all persons shall have equal access to its programs, facilities, and employment without regard to race, color, creed, religion, national origin, sex, age, marital status, disability, public assistance status, veteran status, or sexual orientation.