Pot-in-Pot production is pretty basic in concept.  A trifle expensive to build and
install at first, but it's well worth it in the long run.  It does fairly quickly pay for
itself by reducing watering, as well as reducing labor in having to continually
stand up fallen plants after windy days.

Depending on where your production facility is located, PIP can make a world of
difference in your operation.  Essentially, you either excavate an area, or build a
raised bed to start, depending on the size containers you expect to use.

In my case, a few drain lines were run under the bed, and the bed was graded so
that water would drain to a ditch about 10 feet from the bed's end.  The bed was
framed with treated lumber, and the frame was held in place with 3-foot treated
2x2" stakes driven into the ground.  The frame was then filled with sand.  The
failed attempt at a PIP bed that I mentioned on another page used sand that was
too fine in consistency, and it drained poorly (hardly at all, really).  Be sure to use
a coarse grade sand to ensure that water doesn't remain where it shouldn't.

I used a family member's auger to drill holes into the sand, and then "planted" an
empty Nursery Supplies Inc Classic 400 (1 gallon) pot into each hole.  This is
referred to as a socket pot, as you can likely imagine.  A "liner" pot (with a plant in
it) is placed into the socket pot, and the plant is then grown for the normal
production cycle.  When it's time to sell, you just lift the plant and liner pot out of
the socket pot.  You then replace the sold plant with a new one for a new cycle.

Additionally, I used drip irrigation, since watering with sprinklers is notoriously
wasteful and subject to landing in places it's not intended on windy days.  I used
two shallow well pumps to supply water from a pond on the property.  I ran lines
underground from the pond to the greenhouse, where I had the pumps housed.  
Supply lines were run to the PIP bed, and each pot had a 1/4" line and dripper run
to it.  Since I was only able to look in on my charges on the weekends, I installed
electric valves and a timer to take care of the watering between visits.  This
particular investment was a lifesaver.

The noteworthy benefits:
-Roots are protected from the hot/cold sides of pots in full sun.  The side of the pot
facing the sun can heat up to pretty high temperatures...and can damage tender
-Excessive rises and dips in air temperature are tempered by the ground, which
buffers and protects roots.  This translates to lusher, healthier plants.
-Since they're effectively anchored in the ground, plants are much less prone to
being blown over on windy days.  This saves damage to plants that break when
they fall, and on labor required to stand them back up.
-Because of how you set them up, plants are automatically spaced, depending on
how you space your socket pots.  This is good for airflow and reducing the length
of time leaves remain wet after rainfall or overhead irrigation.  This translates to
fewer and less severe cases of fungal diseases.
-Since the ground keeps root temperatures cooler, the plants lose less water to
evaporation, and thus require less frequent watering.
-Coupled with using drip irrigation, much smaller quantities of water are required
to keep your green and blooming friends properly hydrated.

The two really noteworthy drawbacks to installing a PIP system are cost and
initial labor to install it. It requires a relatively large investment of each to get it
going.  However, as I've mentioned here, both are more than made up for in time,
water, and labor savings over the long run.  Should you have the means and
determination, I highly recommend it.

Click on any thumbnail below to see the full-sized image.  Enjoy!
Bed 2 from the South Sep 2004
Bed 2 May 2005
Closeup of 1-gallon perennial in Bed 2 May 2005
Bed 2 from the north June 2005
Leftover sand from Bed 2 June 2005
Final irrigation system configuration Oct 2005
Remains of Bed 1 Nov 2005
Bed 2 from the northwest Nov 2005
Bed 2 from the south Nov 2005
Bed 2 slumbering Feb 2006
Closer view of Bed 2 Nov 2006