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Container plants for
desert restoration
David A. Bainbridge
Restoration Ecologist
Why containers?
• Container planting is desirable because direct
seeding may succeed only once every ten
years in the desert (Cox et al., 1982)
• Good seedling survival and growth from
containers can be expected even in areas
with less than 3 inches [75 mm] of rain per
year when plants are:
– Well prepared in the right container
– Protected from grazing
– And get supplemental water as needed
Deep containers
• The choice of container type is guided by
ecological, physical and bureaucratic issues
• Use local site adapted seed
• Deeper (taller) containers have often been
more successful
• The more uncertain the climate and the
bureaucratic environment - the bigger/deeper
the containers should be
Production goals
• A container that will produce an
acceptable seedling at the highest
practical growing density, in the shortest
time, at the lowest cost
• Easy to handle and plant
• Suited to the project, site environment,
and planting and maintenance program
Restoration v/s landscape plants
• Restoration goal:
roots, toughness,
minimal shoot
Restoration
Landscape
• Landscape goal:
maximum shoot,
minimal root, fast
growth in nursery
Root development wanted
• Small shoots and
vigorous roots are
wanted
• The root/shoot ratio
should favor roots
• Fertilizer
management and
pruning may be
used to get good
root/shoot ratios
Container options
Supercells
• The ten cubic inch
plastic cell fits in a rack
• The plastic holders are
relatively fragile
• I like to transfer cells to
5 gallon plastic bucket
with a rack for planting
• Deepots add volume
and depth
Plant bands
• Plant bands are square
tubes made with folded
and glued plastic or foil
coated cardstock
• Holes in the sides can
lead to root tangles
• Seams should face in in
blocks to avoid melting
glue
• Plant bands can be
removed with minimal
root disturbance
Half high
Smoothwall PVC 6” x 16”
If drainpipe or less shiny plastic is used it can be
hard to get the plants out without disturbing roots
• The bottom can be closed with a crossed wire
and wire mesh disk or shadecloth or screen
taped onto the pipe
• This summer I am trying Tubex shrub plant
protectors as containers. Pulling it up after
planting would give a secure and effective
protector
Container suppliers
• Deepots and
Treepots from
Stuewe and Sons
www.stuewe.com
• Plant bands can be
custom made at any
size
Other options
• Citrus pots and tall
containers
• It is often good to
use tapered pots
upside down - this
minimizes root
disturbance on
planting
Tall pots
• The Center for Arid
Lands Restoration
at Joshua Tree
National Park
pioneered the
development of the
Tall Pot made with
32 inch tall, 6 inch
diameter PVC pipe
(Apache 2729)
Jelly Roll
• For some situations and
species the best
container is no
container
• Plants are grown in a
loose soil mix, then
rolled bareroot in a roll
of moist absorbent
paper or Kimtex
• A cooler with some ice
can hold hundreds of
plants
Other challenges
• Timing - what do
you do if contracts
are delayed?
• This field of cholla
was finally plowed
down - it became
too hard to handle
after a long delay
Soil Mix
• Many desert species have limited defenses against
root rots, damping off, and other pathogens
• They may also have high oxygen demand
• Well drained soil mix (washed plaster sand is often
used with some compost or organic matter)
• Experimental trials are recommended before big
grow-outs are attempted
• The soil mix must fit the container, plant species,
irrigation, and nursery operation
Inoculation
• VA mycorrhizal fungi (phosphorus) and
rhizobia (nitrogen) may be important for
very large disturbances such as mines
and borrow pits but on most sites native
species will colonize roots and wind will
blow in more inoculum
• If needed collect inoculum on site and
put in planting holes
Handling
• Efficient and gentle handing and staging
is important to improve survival
• Dropping or careless handling can
shear roots
• Contract growing is often more efficient
than starting a local “nursery” which is
labor intensive and 24/7
Cost per survivor
• It depends on the year, the site, the planter
and the species
• With water and plant protection
• An average survival and cost per survivor
might be something like
Supercell
Plant band
Tall pot
40%
60%
95%
$15
$10
$30
These costs may seem high - but the plant itself at the nursery may be
only a dollar or two. Transport, planting and aftercare are costly.
The right choice?
• There is no one container or production
system suitable for all conditions and species
• Deep (tall) containers generally result in
higher survival and better growth
• A combination of small through large
containers is often best
• This might include 10% tall pots, 20% half
highs, 30% plant bands and 40% supercells
Out of season
• Growing plants out of season never
seems to work (we have tried)
• When contracts come at the wrong time
it is better to insist on waiting
• Build in sufficient time to collect seed,
prepare sites and grow healthy plants
• This often requires educating managers
who don’t understand plants
Everything has to be right!
• Neglect of any of the key factors may lead to
complete failure or very low survival
• Plant protection rarely receives sufficient
attention (see plant protection presentation)
• With careful preparation, good protection and
some water -- excellent survival and growth
may be achieved with minimal water use,
limited maintenance, and low cost
• Rainwater harvesting can help long term
growth and survival
The toughest conditions
• Off road vehicle
damage A-BDSP
• Far from the road, 4wd
access only
• Soil pitting, direct
seeding (few seedlings)
and container planting
(successful)
• Low budget - or the
road could have been
graded out
More information
• Available from
Island Press,
Amazon or your
local bookseller
• See other
presentations in this
series
http://works.bepress.com/
david_a_bainbridge