Automated Benching Systems
Last month’s article focused on options for materialmovement when growing on the floor, but what about growing on bench systems?Creating the proper environment for crops should be the single most importantcriterion when deciding on a production method, though in the past, economic orlabor considerations have been the prime decision factors. The traditional viewwas that growing on the floor (without flood floors) was the least-expensivealternative and offered the most flexibility and that growing on benches costmore money but was more accessible.
Advances in automation technology have changed thetraditional reasoning, making this more of a personal-preference decision.Flood floor systems and automated benching systems cost approximately the same,and automation exists for both systems that allows efficient use of labor andmaximum flexibility.
When a grower decides to grow on benches, a mobile systemshould be seriously considered. These systems are available in varying degreesof sophistication. Many articles have been written on operations in TheNetherlands where only four people are needed to operate a 4-acre range. Thebench systems in these ranges are totally automated, and people, theoretically,never go in the growing range. I have seen one of these operations growing fouracres of Boston ferns, and it was an extremely efficient operation. However,U.S. growers cannot make a living growing one crop with a 16-week cycle.
Systems do exist that provide the American grower with an extremelyefficient method for moving large amounts of product in a relatively shortperiod of time without total automation. Automated bench systems can bedesigned with or without flood bottoms, allowing the benches to be both atransport system and an integral part of the irrigation system, from plastic ormetal, with mess or solid bottoms, etc. The only real defining characteristicof automated bench systems is that the benches are designed to ride on a systemof rails that allows them to be moved from the headhouse to the greenhouse andon to the shipping area. In many instances, the movement to and from theheadhouse is done using a powered transport line, while the movement of thebench to and from its position in the greenhouse is done manually. It is possiblefor two people to easily move even a 20-foot bench. Because of this, any givenbench can be placed in position on the transport line, providing theflexibility so crucial for the American grower. This manual movement issurprisingly quick.
To be most efficient, a bench system must be designed aspart of an integrated system. The flow of the crops through both the greenhouseand the headhouse must be considered. Optimally, newly planted crops will enterthe greenhouse on one end, and finished crops will exit the greenhouse on theopposite end, creating a circular product flow through the facility. Thegreenhouse itself must be sized to allow maximum space utilization. A properlydesigned system of bench and greenhouse uses space as efficiently as a floodfloor system. The headhouse must be planned to allow for automatic washers forthe benches as well as equipment to automatically load the benches. Thissupplemental equipment need not be part of the initial investment.
Benching in the Future
One of the most exciting aspects of automated benchingsystems is the future potential. Technology is being tried in a greenhouseenvironment that uses bar coding to identify the location of every bench anddescribe the plant material on it, an invaluable aid in inventory control. Thisinformation can also be used to guide the irrigation equipment so thatfertigation is unique to each bench.
Cynics may say that automation has made both benching andfloor-growing systems very expensive. However, this is only true when lookingat the initial installation cost. As with any automation decision, it iscritical to look at total operating costs over the life of the equipment. Whenlabor savings, efficiencies and standardization are considered over the life ofthe product, the cost is very reasonable.
With all the technology available, and the size of theinvestment required, how does a grower decide on the proper system? The keys tothis decision are no different now than 20 years ago. There never has been noris there likely to be a substitute for the instincts of the grower. See whatothers are doing, decide what you need, consult your manufacturer and trustyour instincts.