Rolling benches offer the grower numerous benefits. Most notably, they allow for more efficient use of space, but that is not the only advantage to them. Growers that install rolling benches can expect to see savings in labor, a reduction in incidences of disease, and a more ergonomic work environment for employees. But first, lets consider what a rolling bench is.
What Rolling Benches Are
As their name implies, rolling benches are surfaces for growing plants that move back and forth on rollers. They are thought to have first been used in the Netherlands in the 1980s before they started to become available to North American growers and to take their place in North American greenhouses. They are alternatively called rolling tables, rolling shelves, rolling containers, or Dutch trays, though “rolling benches” are the most commonly used term for them. At first, they were mostly just found in research greenhouses, and then migrating to the world of floriculture and agriculture, and commercial greenhouses. Now, rolling benches have become a staple in the production of high value crops and other horticultural crops.
Rolling benches vary in size with widths generally between four and six feet (1.2m to 1.8m), and lengths between ten and twenty feet (3m to 6m). They can be any size though, sometimes custom made to fit a grower’s exact specifications. Like any bench for growing plants, rolling benches serve several crucial functions, they provide a stable, well-drained surface for growers to easily tend to and access their plants. They are often customized in size and shape, based on the types of crops being grown as well as the environments they are being grown in, along with the physical layout of the grow space. They can be just a few feet long to extremely long, with some as long as 200 feet (61m).
Rolling benches are almost always made of metal. They can be aluminum or steel, galvanized or stainless. They often have food grade plastic, nylon, or polypropylene components. A typical rolling bench consists of the table or platform, which rests atop a set of two inch (5 cm) diameter pipes on which the table can roll. Sometimes there is a handle to turn in order to roll the table, but often they are just manually pushed from side to side as needed. A properly functioning rolling bench will offer very little resistance, and even if it is fully laden with just watered plants, it should glide almost effortlessly.
The movement of the rolling bench tops is often done by hands. In some high tech greenhouses though, they can be moved automatically or by a controller. Some are a combination of both manual labor and automation, depending on the needs, and of course, the budget of the grower.
Beneath the rolling pipes are the supports and table legs. The legs often set into feet that are affixed to the floor so that the whole table does not move, only the top. Speaking of the top, it is usually an expanded metal mesh, which allows for drainage of excess water onto the floor. Custom- fit trays can be set into the tabletop if the goal is to perform ebb and flood watering or if the grower wants their plants to absorb moisture, nutrients, or treatments from the holes in the bottom of the pots.
Advantages of Rolling Benches
The benefits and advantages of rolling benches are intertwined. They form a positive feedback loop where one advantage fuels another. They can be mostly divided up however into three main advantages; more space to grow with higher efficiency doing so, labor savings (and thereby money savings) and ergonomics, and healthier, higher yielding plants(i.e., more revenue).
Space and Efficiency
Arguably the biggest advantage to rolling benches is that they allow more production space in the same footprint as compared to fixed or stationary benches. They do this because there a walkway around and between each bench is not required, since the table rolls, a walkway can be “created” by pushing the bench you wish to approach to one side, or by pushing the adjoining bench. How much space can be gained depends on the space and configuration of your growing room and the benches you select; averages of space gained are all over the board. Some growers claim 24- 33 percent, others claim up to 50 percent gains in space. What this means is that up to 90 percent of your growing space can be utilized with rolling benches versus an average of 60- 75 percent with stationary benches. This bench space efficiency can be calculated in any grow room by measuring the area of space that the benches occupy and dividing that by the area of the entire grow room.
Rolling benches do not just save space though; they also allow for the more efficient use of utilities and resources. Your energy expenses are reduced on a per plant basis because you can grow more plants in the same space. Your water use will become more efficient because there is less vacant space for irrigation water to splash onto. Ditto for pesticide and nutrient applications. All of these gains in efficiency and increased plant production will improve your bottom line significantly. Even routine processes like potting, spacing, trimming, harvesting, etc. become more efficient because there is less moving around between plants since there are more in the same space.
Labor
Rolling benches not only save labor costs, but they also make growing quality plants easier and are more ergonomic than growing only with or on fixed benches. They are setup such that workers do not need to bend over to tend to plants such as for floor-grown or low bench-grown crops. Floor-grown crops may allow a grower to use 8-15 percent more of a greenhouse or growing space’s footprint, but it is impractical on any large scale. That difference in floor coverage compared to the use of rolling benches, is easily and quickly made up by the increased labor efficiency offered by rolling benches. When plants are at the desired height on a rolling bench, and the full range of motion and ease of movement of rolling benches are utilized fully, the entire greenhouse work environment is improved. This reduces the likelihood of work-induced injuries, potentially lowers insurance, and workers’ compensation, but more importantly, it is the right thing to do for the health and safety of yourself and your employees.
Labor costs (hours paid for) can also be reduced when using rolling benches. In some operations, it can be reduced by as much as 40 percent. When irrigation is added to a rolling bench, either in the form of ebb and flow, drip irrigation, or overhead watering, additional irrigation labor is cut too. Add in any other form of automation and it can be cut up to 60 percent over manually cultivating the same crop on fixed benches. The actual amount of savings will be unique to each grower and operation, but the savings are there to be had. Reducing the amount of labor in the greenhouse can also increase the level of hygiene as there is less chance of cross-contamination between plants by workers unknowingly spreading pests or pathogens.
Healthier plants
Rolling benches help to keep plants healthier. The particular configuration and type of setup will dictate which plant health benefits and to what extent you will realize them. Most rolling benches are open, metal mesh types, which greatly improve airflow around the plants. Increased airflow reduces humidity which in turn reduces the risk of some plant diseases. Plants grown on rolling benches have much better airflow than plants grown on the floor and because many stationary benches are made of wood which does not dry as quickly as metal, they have better sanitation as well. This airflow also helps with the distribution of heat during colder months, more evenly to the plants.
Rolling benches are conducive for the precise application of irrigation, nutrients, and pesticides (including plant growth regulators). This can be either through automation or ebb and flow type irrigation or manually, because rolling benches can allow employees to better access plants to make sure that they get even applications and coverage. Some rolling bench setups can allow for compartmentalized ebb and flow to further reduce the risk of spreading disease by not exposing all plants on a bench to the same irrigation water.
Heating can be incorporated into rolling benches, as well as other climate controls to help create as near a perfect environment for your plants as possible. This, along with the airflow will help to eliminate excess moisture on and around your plants which will prevent such diseases as molds, mildews, and root rot from setting in. Different climatic zones can be established on different rolling benches to accommodate the differing phases of growth (such as the vegetative or the flowering stages) that the plant is in or depending on the temperature needs of a specific species of plant.
Considerations when Selecting a Rolling Bench
So, you have decided that rolling benches are the way to go, to increase your yields and improve the health of your plants. How do you determine which configuration or which rolling bench is right for you though? You will need to assess how many people need to access your space at one time and consider what other types of accessibility you will need before you cover all of your available greenhouse or grow room footprint in rolling benches. Will you be needing to pull carts in the aisles between rolling benches? Do you have a mobile spraying unit that you will need to pull or roll between the tables? Will you be harvesting right at the bench? Answering these questions will help you decide whether you can put rolling benches end-to-end, side-to-side, or if you should leave room for an aisle. If you are giving different treatments to different plants at the same time, you may also want to cluster your rolling benches so as not to accidentally have one crop receive treatment meant for another or have over-spray inadvertently and adversely affect one of your crops.
You will need to determine the bench height that is most conducive for plant handling or if you have them, automatic operations. Decide how much air space you need to have circulate around your plants. Select a bench that can handle the weight loads of a fully saturated crop. Concurrently, select a bench with proper supports for the weight of your crops so that it cannot only hold up to the weight, but do so for extended periods of time without undue stress on your rolling bench tops. You do not want to find that the floor of your rolling bench is bowing or sagging under the weight of your plants. The prevailing guidelines suggest that each square foot of bench area should support about 25 pounds (11.3 kg). Galvanized rolling benches are generally the way to go. They are long lasting and strong; they are resistant to rust and decay. They are also easier to maintain and keep sanitary than other bench types.
Ultimately your budget will inform which rolling bench you opt for but look beyond the short term as the increases in yield and efficiency you will gain with rolling benches will justify adding more or adding on for subsequent crops. Optional add-ons and customization will further make your rolling bench an ideal fit for your unique growing operation. If you can budget for it, select a bench that has the capability of adding on over time, such as one that can support irrigation equipment or trellising to support upward growing plants.
Other Points to Consider
While nearly every growing operation would benefit from the addition of one or more rolling benches, there are a few things to consider regarding them and their use. Rolling benches are not designed for retail operations; they are designed for production and cultivation. They are suitable for high volume greenhouses as well as wholesale operations. They are not designed for their “shopability”. When rolling benches are properly deployed and in place, there should not be aisles on either side of all of them, in fact the fewer the aisles, the more efficiently the space is used. Fixed benches with dedicated space are more appropriate for retail staging, selling, and displaying of plants.
Access to plants in the center can be a challenge until you learn what system works best for your operation with rolling benches. Automation renders this problem negligible, but when relying on human labor, a new “rhythm” will need to be put in place to make the most of the increased efficiencies with rolling benches. Cost is of course another consideration to adding rolling benches to your growing operation.
Rolling benches will cost more than most stationary or fixed benches. This might mean transitioning to all rolling benches is not feasible all at once, but they may have to be deployed in phases. The increased cost of rolling benches however will be easily absorbed by the increased efficiency offered by utilizing them. Costs to be recouped will vary of course based on the size of the area where they are to be used, the types of crops grown, the irrigation requirements and respective equipment and the specific needs of each unique grower and growing space. It is always possible to start with a basic rolling bench and then add on to it over time as well. Regardless how many rolling benches are used, what configurations are set up, or what crop is being grown, the results are predictable; rolling benches increase harvest and plant yields, keep your plants and growing areas more sanitary, keep your labor costs down and employees safer, and last, but certainly not least, they will help you to realize greater profits.
