In the 2017 survey of labor and mechanization of New Jersey’s nursery industry, pruning was ranked, the third most important operation, that needs mechanization the most (41 responses). In spite of obvious benefits such as efficiency, quality, and consistency, lack of practical information about the mechanized pruning is delaying the rapid adoption by container nursery growers. This article summarizes inputs from Chris Ruske of (Cumberland Nursery), Donald Blew (Centerton Nursery) and Ed Overdevest (Overdevest Nurseries) on pruning mechanization, shared during the panel discussion at Clayton in Gloucester County in January 2018.
Moving pots through a rotating platform
There are multiple combinations of size and shape for the extensive variety of container plants grown by New Jersey nurseries, with no one specific machine available that could serve as one solution for all pruning and trimming needs. There are probably five or six different companies in the U.S. that are building trimming machines. However most of the machines are single use arrangements, where a plant goes in a machine, and then it moves on. However, nurseries can design their own pruning machines. For example, Overdevest Nurseries, based in South Jersey, designed their own unit which was then custom built by Bouldin & Lawson. As seen in this video Overdevest Trimming Machine there is a rotating platform with sickle bar trimmers mounted on the top and sides. It allows for a clean cut, for all the shapes and sized plants they grow. The machine operates alongside the house, plants are placed on the conveyor, trimmed, after which they go back to the same spot in the house where they came from. The clippings are simultaneously collected in a trailing wagon that is attached to the machine. This sanitation process can considerably reduce pathogen build-up and disease pressure in the plant growing area. The machine, with the help of two men, does 5-15 plants per minute – depending on plant size (1 gallon to 7 gallons).
Walking the machine over-top the plants
At Centerton nursery, beheading stems from growing ‘Knock Out’ roses, is that they were tired of. They had to have this popular variety of roses, basically staged in about two week crops so that they always had flowering knockouts. “We were not trying to remove a lot of material, were just trying to remove the last four to six weeks of growth to get it back to where it is going to reset buds, so we built some fairly simple machine that runs out of thousand watt gasoline generators. There are adjustable sickle bars that are mounted on the side and the top. You can trim a cone, a sphere, or basically whatever you need to trim. We just walk the machine right over top of the roses” said Don blew. It is about efficiency and streamlining things. It might not save as much labor as you think, but it does make your operation run smoother. Centerton also has a progressive machine where the plants are constantly moving through a series of blades. It is less accurate on the precision side of it, but the machine will run through seventy pods a minute with a crew of about five guys.
According to Chris Ruske of Cumberland Nursery “getting the machine to work correctly in the first place is a hassle. However, you cannot beat the consistency. Just like the robots, it is there every day, it’s usually working now that we have gotten the bugs worked out, and it’s reliable. The downside is that you have to have someone who really knows how to fix it”. It is an emerging technology still, and the biggest problem is getting the product to and from the machine efficiently. The machine is very accurate in what it’s doing, but it’s slow because you’re only doing one at a time, however you cannot beat the consistency”.
Low tech, low cost solutions
You don’t have to get extremely high tech either. There’s a lot of things you can do to increase efficiency. Again, Don Blew, “Instead of having workers out there with head shearers, we bought a few gas powered shearers. For hoop houses, we knew that we couldn’t go in there during the winter so we decided to go to electric. It was cumbersome with power cords but we felt it was efficient. We ran two-hundred foot cords outside the house to a generator and we got a lot of work done this way”. Then, there are ones which resembles weed whacker, but you can put a sickle bar on it at an adjustable angel, you don’t need to bend over if you are trimming lower plants. “Just remember to think inside and outside of the box”.
For the mechanization of potting, and spacing, please read following articles.
https://plant-pest-advisory.rutgers.edu/spacing-robots-experiences-of-the-container-nursery/
https://plant-pest-advisory.rutgers.edu/transitioning-to-mechanized-potting-adopters-perspective/
