Labor-saving ideas

Labor is still the greatest cost in the production of plants, accounting for about half of production costs. Unloading trucks, moving and spacing containers, loading carts and conveyors, and getting equipment to the right location requires time and effort. A review of where the labor input goes in the production of a flat or pot will indicate where potential savings can be made. Can you answer the question, “How much time does it take to accomplish a particular task?”

Examples of common tasks that could be reduced or eliminated with equipment available today:

• Workers often drop seeds individually into plug trays. A low cost vacuum seeder would speed up this operation.
• Employees sometimes carry hanging baskets two at a time down a 100-foot aisle to be placed on overhead racks. A $500 cart could handle many baskets at one time.
• Having a person stand at the end of a line to insert tags as they come off a conveyor is very costly. A tagging machine will place a label in each pot or tray.
• The bulk of irrigating crops in a large greenhouse should be done with an irrigation system. From overhead sprinklers, to drip tubes, to boom irrigators, systems are available to water all types of containers and plants.
   

Equipment should be compared on a payback basis. How long will it take to pay off the investment that I make? This requires getting a quote on the cost of the machine and putting a dollar value on the savings in labor. Dividing the cost by the savings gives the years to payback the investment. A payback of less than three years is good for most equipment.

One of the best ways to reduce labor costs is to reduce the amount of walking that employees have to do. An average time to pick up or set down a flat of plants is 1.5 seconds. Research has shown that carrying or walking can be figured at 4 feet per second. At a labor rate of $10 per hour, walking 10 feet back and forth in order to place a flat of plants on a bench adds 2 cents to its cost. And walking to the far end of a 100-foot greenhouse costs $0.15. And when you stop to ask how many times is the flat or pot handled before it is sold, it’s easy to see how these costs add up and why the use of carts and conveyors makes good business sense.
 

Carts and conveyors

All sizes of operations can benefit from carts. Today you can purchase carts that:

• Fit into the narrow aisles between benches.
• Carry 30 to 60 flats at a time.
• Tow a garden tractor or electric cart, creating a train to carry as many as several hundred flats.
• Fold or disassemble for easy transport when empty.
• Make handling plants more convenient for the grower and retail customer.
   

Carts are low-cost tools to reduce the cost of plant handling.

There is also a large selection of conveyors that have application in greenhouse operations.

• Belt conveyors work well for moving boxes, bags, bales, pots, flats, and bulk materials. A light- to medium-duty unit is adequate. Folding and section conveyors make relocating easy.
• An overhead conveyor can move materials anywhere there is a track. Its low cost and simple installation make it a good choice for moving plants from the head house to the growing area.
• Gravity conveyors are ideal for moving boxes, bales and flats, either horizontally, by manually pushing the material along using the force of gravity. Close wheel or roller spacing is important to smooth material handling. These are readily available in used condition.
   

Conveyors are available in many sizes and adapt to many tasks. And they free employees for more skilled work.

When you’re able to do that, the quality and profitability of your operation will increase.

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.