Find your flow

Transplanting and potting operations add considerable cost to the production of a crop. Developing a smooth flow of materials from the bale of growing mix to the production area can reduce these costs considerably.
 

Determine initial cost

A simple of way of evaluating your whole operation is to total up the cost of employee time for the day and divide this by the number of pots or flats transplanted. For example, if you had four employees working the transplanting line and at the end of the day they had filled, transplanted and moved 1,200 flats to the growing area, then each employee, on average, produced 300 flats (1,200 ÷ 4 = 300).

To figure the cost per flat, you need to total up the wages, including benefits, for the four workers and divide that by the 1,200 flats. If we assume the employees worked 8 hours and were paid $10/hr then the cost per flat is about 27¢/flat (4 employees x 8 hours x $10/hr ÷ 1,200 flats = 26.7¢). Gathering the output and costs over several days will give you an average.

The output per worker can give you a benchmark to look at alternatives that may provide a lower cost per flat. In the above example, increasing the output to 1,400 flats per day by moving them on carts instead of hand carrying will lower the cost to 23¢/flat. The cost will vary with a number of factors, including: the number of plugs per flat or the size of the pot, the equipment used for filling and dibbling and the method and distance for moving the flats to the growing area.
 

Look for improvements

The following are some techniques that successful growers are using to improve transplanting:

• Handle pots in carrier trays. There are trays to handle most pot sizes and shapes. This speeds moving pots and is required with most container filling and handling machinery.
• A good workstation layout has everything in easy reach of the transplanter. The height of the station should be adjustable, or a floor step can be used to place the top of the work area at elbow height. The reach from the normal arm rest position to get materials should be limited to a 24-inch radius for women and 27-inch for men. A supply of prefilled flats and a cart to place transplanted flats should be located close to each worker.
• For small growers with a few hoophouses, set up the transplanting stations in the greenhouse. These work tables should be portable, preferably on wheels so they can be moved from one end to the other as the growing area is filled. They should also be light enough to be easily moved from one greenhouse to another.
• In larger operations, a transplanting conveyor can improve the production output versus using a fixed station. One grower reported that moving his perennial transplanting operation from outdoors near the growing beds to the headhouse doubled the output per employee and cut cost in half.
• Reduce the amount of walking time. A 10-foot round trip to set a flat onto the growing area costs at least 2¢. Making a round-trip to the far end of a 100 foot greenhouse costs 15¢ at a pay scale of $10/hour.
• Develop an efficient system for moving the containers from the transplant area to the growing area. Carts, wagons, conveyors or motorized vehicles are frequently used. Carts should be designed with adjustable shelves to handle different size plants. Large wheels and a paved walkway make pushing the cart easier. If the distance to the growing area is more than 200 feet, use an electric or motorized pull vehicle and carts or wagons. Leave a center access aisle with doors on both end of the greenhouse so the plants can be moved close to where they will be set.
• Low-cost, overhead trolley conveyors work well for some growers with compact greenhouse facilities. A four-shelf, trolley-mounted rack is easy to push on the steel tracks. Switches can be set up to allow movement to several greenhouses and the headhouse.
   

One way to offset the increasing cost of labor is to improve the efficiency of your present operations. An efficient work area and easy method for moving plants and materials are areas where the greatest gains can be made.

Bartok is a regular contributor to Greenhouse Management and an agricultural engineer and emeritus extension professor at the University of Connecticut. He is an author, consultant and a certified technical service provider doing greenhouse energy audits for USDA grant programs in New England.

Have a question? You can write John at jbartok@rcn.com.