Tech Solutions: Growing media preparation

BUDGET SOLUTION

Uniformity in plant growth depends on uniformity of the growing mix. Today, most growers use a commercially prepared growing media. After the components are mixed, the media is placed in bags or bales. The bags usually hold 2.8 or 60 cubic feet of mix and are shipped palletized. Bales are compressed mix and, depending on manufacturer, hold 3.8, 40, 55, or 100 cubic feet of mix. The compressed bales reduce the volume and the cost of handling and shipping. With a yield of up to twice the volume of the bale when processed and fluffed, the cost per cubic foot is considerably less than bag mix.

Fluffers
Both bag and bale mixes can benefit from fluffing. It can maximize the yield. This procedure breaks up any clumps and gives a light uniform mix that has good drainage and aeration. Water can be added during this operation to moisten the mix to reduce dust and increase the moisture content. The increase in the number of flats filled and the reduced labor of hand breaking the bales help to pay for a fluffing machine.

Fluffers are designed to loosen the mix without separating or breaking down the components. Usually they are placed over an inclined conveyor that transports the mix to a potting table or container filler. Some are designed to fit directly over a potting machine. The small bags or bales are placed in a hopper and broken up by hand. Instead of cutting blades, such as are used in a shredder, the fluffer uses tines to break apart the clumps. Water from nozzles can be sprayed over the mix as it is conveyed. The loosened mix provides a more uniform fill for the containers.
 

Bale breakers
These machines are designed to process the large compressed bales. Sizes are available to handle bales from a 4-foot cube to the 100-cubic-foot size. Bales can be placed in the hopper by a hand pallet jack, fork lift or a portable gantry crane. A 60-cubic-foot bale weighs from 900 to 1,250 pounds depending on the mix. A typical 55-cubic-foot bale will have enough mix to fill 1,200 to 1,400 806-cell trays.

Bale breakers are usually designed for easy loading of the bale into the hopper and removal of the plastic wrap. They work either by shearing the mix off the bale with a knife action of a scraper blade or by a series of rotating tines. Movement of the bale is with hydraulic cylinders or a walking floor. Some units, such as the Bouldin & Lawson Bale Buster, are available with a fluffing unit. Bale breakers usually cost in the $15,000 to $20,000 range.

When selecting a machine, look for one that will handle the size of bale you use, is easy to load and supplies the mix at a rate that complements the container filling machine. If you plan to move it, look for one that has wheels or can be picked up with a fork lift.

With a potential 25 cents to 30 cents/flat savings in media and labor from using large compressed bales and a bale breaker as compared to 2.8 cubic foot loose bags of mix, it takes only 60,000 to 80,000 flats to pay back the cost of a $20,000 machine.

With large bags and bales becoming available from more manufacturers, the fluffer and bale breaker machines are a necessary part of the plant production process. These machines save both on the cost per flat and the handling labor.