How do Ebb & Flow benches work?
Modern Ebb & Flow benches provide a sturdy, level, waterproof bench top surface on which the plants are grown. The benches are designed to be perfectly level, and the bench surface (typically vacuum-formed polystyrene) has drainage channels and plumbing wells to ensure complete drainage of irrigation water from the crop when the irrigation cycle is done. When the crop requires watering, the irrigation solution is pumped into the bench, and then allowed to drain, and is returned to the holding tank to be reused. The process from starting a watering cycle until the bench is at full irrigation (typically about 3/4″ of water), and then completely drained again usually takes 15 to 20 minutes. During this time capillary action within the plant root media takes up the irrigation solution, thoroughly watering the crop.
What sizes of Ebb & Flow benches are available?
We currently stock the polystyrene bench trays in three widths ( 4’0″, 5″0″, and 6″0″) many additional widths are available as a special order. Benches may be any length, but usually must be at least 7 1/2 feet long. They can be as long as you want, but usually benches longer than about 60 feet will have the polystyrene tray bench tops in two or more sections. All benches from Innovative Growers Equipment, Inc. are custom made to order. While the standard bench height results in the bench top surface being approximately 30 inches from the floor, any bench height (at least 13″ from the floor) can be manufactured.
Can Ebb & Flow benches be rolling benches?
Yes, all our growing benches are available as either stationary or rolling benches. Rolling benches (5-foot width or wider) can roll side to side approximately 10 inches each way. This allows for an access aisle between any neighboring two benches of about 20 inches. Benches can be laid out so that there is only one 20 to 24-inch aisle in a bay of the greenhouse. This maximizes the use of the space, spreading the fixed operating costs over the maximum square footage of the production area. Remember when you use rolling benches, you do gain maximum production area, but you do give up some access to the crops. Typically rolling benches are used in areas that are strictly for production, and fixed benches are commonly used in retail areas where easy customer access is important.
How much slope is needed with Ebb & Flow benches?
Actually, the correct answer is none! This is a common misconception among people new to Ebb & Flow benches. In almost all cases, the bench top surface should be perfectly level. The reason for this is that Ebb & Flow benches are designed to water every plant on the bench perfectly evenly. If the bench top surface is sloped, the plants located at a higher portion of the bench will receive water later, and be in contact with the water for a shorter period of time. This will result in uneven watering of the crop, negating one of the main advantages of Ebb & Flow benches. The vacuum-formed polystyrene trays that are used in our benches have a series of BOTH deep and shallower grooves molded into the surface, designed to deliver water to all the plants on the bench simultaneously when watering and to drain evenly and completely when the watering cycle is complete.