June 2023 - 26

PRODUCTION
the plugs or cuttings that are located within arm's reach.
A variable speed motor on the conveyor adjusts the
speed from 5 to 50 feet per minute to adapt to the type
of container, the number of plugs/containers and the
experience of the workers.
Transplant conveyors are available in several widths -
8 inch, 12 inch and 18 inch - and in lengths to
accommodate four to 24 workers. Tray supports are
usually adjustable to accommodate the worker's needs.
A counter can also be added to keep track of the number
of containers completed.
MECHANIZE IT
A pot filling machine can also be substituted for the
tray filler. Mechanical potting machines usually contain
a soil hopper that holds 1 or more cubic yards of mix, a
conveyor that lifts the soil and drops it into the pots, a
pot conveyor with holders for each size of pot, and
controls that regulate the speed of the conveyors.
Accessories that may be added include pot dispenser,
soil compaction and leveling devices; dibble or drill for
the plants; return conveyor for excess soil; and a take-off
conveyor for planted pots. Machines are available that
will handle containers from 2.5 inches to 21 inches in
diameter. The machines fill and prepare the pots and
transplanting is done by employees as the pots pass in
front of them on a belt conveyor.
Once the containers are transplanted, they can continue
through a watering tunnel and tagging machine before
being transferred to carts to be transported to the
greenhouse. Additional workers are needed to set the
containers in the growing area.
I recently observed a system with a bale breaker, pot
filler, transplant conveyor and watering tunnel operated by
10 workers potting 30 12-inch baskets per minute (one
person on pot filler, three sticking plugs, three attaching a
hanger, two labeling and one loading the cart). At $14 per
hour pay, the labor cost is only 8 cents per basket.
For larger operations or for growers who are producing
plants year-round, there is an automatic transplanter that
will fit your needs. Machines are available that will plant
from 10,000 to over 50,000 plants per hour. Automatic
transplanters are available with a lot of features that
may or may not be needed. When selecting an automatic
transplanter, consider the following:
* Select a machine that has a production rate that will
match your production needs and schedule. One of
the greatest benefits to having a transplanter is that
you can refill growing areas quickly.
* How quickly can the machine be changed to handle
a different size container, different cell configuration
or a different plug size? Will the transplanter handle
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JUNE 2023 GPNMAG.COM
An accumulation table collects planted trays for forklift transport
to growing areas.
hanging baskets, patio pots and bowls? Will the
machine plant multiple plugs in the same pot?
* Can the picking and planting depth be changed
easily? Are the plugs damaged during handling?
There are several designs for grippers, including
multiple needles and different styles of external
grippers. Some machines incorporate a plug ejector
to loosen it before the gripper holds it.
* How many employees are required to operate the
machine? Basic machines may require an operator and
several persons to supply and remove the pots or trays.
* What information will the transplanter computer
system retain? Number of flats, size of flat, cell
configuration, variety of plant, etc. This information
helps in planning future crops.
Manufacturers usually require that sample containers
and plugs be provided for testing on a machine before
it is delivered. This helps to design the right number of
grippers and the position of plants in a multi-plant pot.
An automatic transplanter may require you to adapt
your production system to handle different plug or tray
sizes. You will also have to purchase or grow uniform
plugs that are at the right stage of maturity. If plugs are
not uniform or if there are skips, hand patching will be
required. If a limited number of containers of a particular
variety is needed at one time, it may be more efficient
to do the potting by hand. With a new price of $20,000
to more than $100,000, automatic transplanters are
generally economical for medium to large growers.
John W. Bartok Jr. is an agricultural engineer and emeritus
professor at the University of Connecticut. He can be reached at
jbartok@rcn.com.
http://www.GPNMAG.COM
June 2023

Table of Contents for the Digital Edition of June 2023
