IPPS Eastern Region Tours:
Outstanding Minnesota nurseries and garden centres

By Calvin Chong, Department of Plant Agriculture, University of Guelph, Division: Horticultural Research Institute of Ontario, Vineland Station

Typical of other U.S. states, Minnesota's economy is robust. Nurseries and garden centres are optimistic and buoyant. This report highlights the tours at the 49th Annual Meeting of the International Plant Propagators' Society Eastern Region in the twin city areas of Minneapolis and St. Paul. These cities are at a latitude close to that of Ottawa. With winter temperatures typically dipping to lows of -25 to -30o F (-25 to -35o C), only the hardiest plants survive this climate.


University of Minnesota Landscape Arboretum
Situated on 1,000 acres (400 hectares) of rolling property located 25 miles (40 km) from the main university campus, this arboretum is the world's repository for Hostas and a children's education program, hosting 20,000 visitors per year. The arboretum left impressions in other ways: 14 well-manicured display and specialty gardens, all plants neatly labelled and some demonstrating how the plants adapt to restricted space. There are 4000 species and varieties, including the maple collection with the famous telephone maple specimen which literally grows straight up; the crabapple collection; the extensive plantings of pines, azaleas, etc.; the Prairie area and seven other native settings; the Pillsbury shade tree area; etc., etc.

     In the shrub rose garden, which includes our famous hardy Canadian Explorer series, rose bushes must survive on their own. No pesticide or winter protection is provided. Some of us had the chance to visit Dr. Harold Pellet's famous test plots - one of few places remaining in the world that identifies and develops winter hardy landscape plants.

Gerten's Greenhouse & Garden Center
Gerten's seems to be the ultimate one-stop depot for the avid gardener. It sells a complete line of hard goods and green products, including annuals, perennials, cut flowers and holiday crops, plus a complete range of nursery stock. Gerten's also provides on-site landscape design service for the do-it-yourselfers.

     As one passes through the main entranceway, flanked on both sides by high-priced metal pottery and attractive hardy mums, a decision must be made to go to the left (B & B trees and containerized conifers and evergreens of all types and sizes), the right (mostly perennials and deciduous materials), or ahead into the new 37,000-sq.-ft. (3,427-sq.-m., $2.6 million) premier complex, which includes 12,000 sq. ft. (1,115 sq. m.) of attached greenhouse space and 12 cash registers for peak spring sales. The Christmas season alone accounts for 12 per cent of annual sales. Inside, Dutch bulbs, grass seeds, fertilizers, and specialty gift items are conspicuously displayed. Close to the perennial area is the 'spooky house' with singing bats and scary creatures heralding the Halloween season.

     The whole retail complex is 'tied together' by the use of bold, neat, and consistent red-on-white (outside) or white-on-red (indoor) signage everywhere - creating a subtle sense of continuity.

     Gerten's produces about two-thirds of all its green products, starting from seeds or rooted cuttings. At the six-acre (2.4-ha) greenhouse production area situated just above and behind the central complex, all 30 greenhouses are interconnected with a labour-saving, manual-driven, monorail system. Most greenhouses are equipped with computer-controlled irrigation booms, which potentially can deliver some 60-odd different watering regimes at 15-30 minute intervals. The water is acidified because of the high pH (7.8 +) and bicarbonate content (320 ppm). About one half of an adjacent 40-acre (16-ha) site is devoted to the production of its full line of nursery stock, and about 50 per cent of this is in containers.

Len Busch Roses
This business prides itself on being the one-stop for florists. Len Busch Roses has been successfully bucking the trend against cheap South American imported cut flowers by producing fresher and better quality flowers. In addition to more than five million cut roses yearly, Len Busch produces a wide range of other cut (alstromerias, liles, gerbers, tulips, snaps, etc.) and potted (kalanchoe, sunflower, cyclamens, etc.) flowers required by florists. Over one-half of the current 500,000 sq. ft. (46,450 sq. m.) of greenhouse space is used for cut rose production. The company employs close to 200 people.

     Len Busch Roses competes and stays on top by utilizing a variety of high-tech or innovative systems such as:
  • a closed recirculating hydroponic growing system for roses and wide use of the inarching method, which produces longer and better quality roses;
  • a state-of-the-art rose machine, which improves grading quality;
  • a computer controlled ebb and flow greenhouse for potted flowering crops;
  • a unique low-pressure boiler heating system, which burns wood at one-third the cost of natural gas.


Bachman's, Inc.
From a humble beginning as a vegetable produce operation in 1885, a switch to flower production in the 1920s and addition of nursery production in the 1940s, Bachman's is one of the largest floral and nursery businesses in the world. At the 500-acre (200-ha) Lakeville growing range, there are 30 acres (12 hectares) of nursery container production, 250 acres (100 hectares) of nursery field production, and eight acres (3.2 hectares) of glass and poly covered greenhouses. Growing and handling its own products allows Bachman's to produce only top quality plant material for their six floral, gift and garden centres, 14 branch floral stores and various other outlets.

     The greenhouse facility is impeccably tidy and obviously well managed. Moveable benches, automatic overhead watering, ebb and flow system and other hardware are state-of-the-art. Typically, bedding plants are grown in the spring, followed by a wide variety of seasonal flowering plants. At our visit, there were lots of poinsettias, chrysanthemums, Asiatic lilies, azaleas, cyclamens, and kalanchoes, to name a few - all of high and uniform quality. At the adjacent 25-acre (10-ha) re-wholesale centre, there were hard goods and a broad line of perennials (487 varieties), containerized shrubs (219), evergreens (133), B & B trees (180) and hardy roses (66). The shipping season was well underway.

Cross Nurseries
Long recognized for introducing many varieties of nursery plants, such as Little Elfie globe cedar, which needs no shearing and the more recent Cross spreading yew, Cross Nurseries is the largest supplier of hardy yews in the upper Midwest. The nursery produces 85 per cent of its own extensive line of hardy shrubs, trees, and perennials on 300 acres (120 hectares) with five nursery fields, all within 10 miles (16 km). Sales go as far as Canada and Alaska.

     The nursery roots about 500,000 softwood cuttings between July and August in various plastic and outdoor beds. In the winter, it also produces another 200,000 deciduous and conifer hardwood cuttings, vines and seedlings.

     In the fall, about 750,000 different shrubs and small trees are harvested. About 50 per cent of this production is sold as bare root deciduous material. Each spring over 2500 two- and three-inch (50- to 75-mm) caliper trees are dug on contract. Although all propagation is being done the old-fashioned way - by hand, plans are underway for new generation greenhouses and propagating areas, and also to get more into pot-in-pot tree production.

     Back in the mid-1950s, Cross was one of the first nurseries to use the original microfoam for winter protection. Today, all its container plants and potted perennials are routinely overwintered under microfoam and white poly and covered with hay.

Bailey Nurseries
As a longtime 'heavyweight,' Bailey Nurseries is known across the continent for its innovative techniques, high quality plants, and its immense holdings - totalling 4,500 acres (1800 hectares) across Minnesota, Oregon, and Washington. What little we were able to see of the Minnesota facilities was awesome, as were the statistics:
  • Five million cu. ft. (141,600 cu. m.) of cold stor­age space, mostly in five huge buildings capable of holding six to seven million bare-root plants on pallets;
  • 1,800 acres (720 hectares) of field stock;
  • 450 acres (180 hectares) of containers, including 80 acres (32 hectares; 90,000 plants) grown pot-in-pot in 5- to 25-gallon containers, and some 45-gallon above-ground containers.

Nord Farm - Seedlings and Cuttings
Bailey's consolidated seedling and cutting propagation at their St. Paul Nord Farm in 1981, and now produces 40 million liners in 129 polyhouses and 40 acres (16 hectares) of seedbeds. This represents 80 per cent of their propagation needs. The other 20 per cent is done at their Western locations.

     Bailey collects most of its own seeds, presently 115 varieties: five per cent in spring, 15 per cent in July, and the rest between September and October. Before sowing, the seedbeds are disinfected with VAPAM at a rate of 80 gal/acre using an orchard-type sprayer. In July, just after sowing, seedbeds are mulched with Sudan straw to maintain uniform moisture and protect the seedlings. Some species such as dogwood and cotoneaster are seeded at this time since they require both warm and cold stratification.

     The seedbeds and seedlings are irrigated by overhead or boom sprayers. Granular 21-4-10 is the major fertilizer source applied and, sometimes urea, when extra nitrogen is required. Until seedlings are established, the seedbeds are continually hand-weeded by a six-man crew. When ready for lifting, a 15-member crew can harvest about one acre (0.4 hectare) of seedlings per day.

     In late fall, the beds are again mulched with Sudan for winter protection. Considering the high value of these seedling crops, Bailey has been reported to be the first to employ helicopters hovering 40-50 ft. (12-15 m) above the beds to prevent late winter/early spring frost damage when seedlings are out of dormancy. At $180 per hour, the cost to hire two helicopters for three to four hours could easily reach $1500 per night.

     At one of the cutting production areas, there are 24 200-ft. long x 25-ft. wide (60.0 m x 7.6 m) greenhouses (approx. four acres or 1.6 hectares) each filled with rooted softwood cuttings. The green­houses are attached on both sides of a huge headerhouse. Each house is equipped with roll-up side vents, cooling fans, shading and overhead boom spray.

     Cuttings are treated typically with powdered or liquid rooting hormones and stuck in ground beds of sand. Liquid fertilizer and sulfuric acid to maintain the water at a pH of 6.5 are routinely dispensed with irrigation. An adjacent open space greenhouse complex (approx. 1.5 acres or 0.6 hectare) is also filled with rooted softwood cuttings. Each bay, with 100,000 cuttings, is equipped with its own irrigation boom.

Container East - Small Containers
This 240-acre (96-ha) farm, acquired eight years ago, produces three million plants, mostly in #1 containers in a one-year turn-around cycle. This includes 200,000 roses and a wide variety of herbaceous perennials.

     The production area is made of a gravel base and tiled subsurface. All run-off is channelled into a 50-million-gallon pond and recycled using two 75 HP pumps, each capable of pumping 15,000 gallons per hour. Nothing is done to specifically treat the water in the pond. The standard potting mix consists of rice hull, peat and coir. This mixture is very porous and has a pH of 5.8. Plants are fertilized usually with incorporated slow-release fertilizers and sometimes a slow-release topdress. Supplemental 18-18-8 is also used for quicker up-front release of nutrients.

     Various strategies are used for weed control: for perennials, soils used for growing perennials are sterilized before potting; for evergreens, the herbicides Goal and Surflan are sprayed over the tops; and, for other woody species, Ronstar is applied as a wettable powder. For winter, plots are consolidated pot-to-pot, or tipped on the side, and covered with Sudan or plastic or a combination of both. About one hectare of Sudan is required to cover one hectare of pots. Ramik is placed amongst the pots for rodent control. Among the cultural practices, pot consolidation is perhaps the most expensive operation, since the procedure is done with manual labour.

Container West - Landscape Materials
This 120-acre (4.8-ha) farm produces one million trees and shrubs in two-gallon or larger containers suitable for landscape planting, for which there has been increasing demand. Typically, these materials are planted in mid-April and cared for much like those at the Container East site. Plants are watered by overhead irrigation. The water runs off into four ponds and recycled after mixing with fresh water from three deep wells. Before winter, the underground lines are pumped out. The aboveground lines are simply left on the ground. Pruning is done by hand monthly on site and sometimes at planting. Some lilacs are pruned with a power trimmer.

Bailey ships 60 per cent of its production across the U.S. and Canada in the first 30 days of the shipping season. A lot of time is saved by using pallets. Without pallets, a four-man crew typically takes six to eight hours to load a truck. With pallets, the same crew can complete three loads in a day or unload a truck in 45 minutes. Also, the plants remain upright and there is little or no damage. Forty per cent of all plants are shipped this way.

Bare-root Stock
With 13 farms producing bare-root trees over a 15-mile (25-km) radius, Bailey re­quires twelve, 12-man crews (including drivers) to harvest the total 500 acres (200 hectares) each year between October 1 and November 8. Also, a 20-man crew is needed to harvest all the bare-root seedling materials. All this material is stored in the huge cold storage facilities at 95-98 per cent relative humidity. Bailey was the first to install automatic humidity and refrigeration controls in bare-root storage rooms. Most of the bare-root shade and apple trees produced in Oregon are also shipped in December to this Minnesota facility to be stored before later shipment to their individual customers.

     For many of us, this half-day tour to Bailey Nurseries was certainly the climax to this year's IPPS tours.