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Introduction
People
use landscape plantings for various purposes. They may plant to join or
to separate landscape spaces, to enhance the value and appearance of homes
or buildings, to produce fruits and vegetables, to shade an area or cut
the wind, or to provide for aesthetics and general well-being.
Develop a plan before planting. You will want to place the correct plant
properly to create the desired design effect and environmental conditions.
Take into account plant needs, such as exposure, amount of light, soil
moisture, pH, and drainage.
Woody landscape plants should last for many years. Most health-threatening
problems which affect landscape plants occur when plants are stressed
by use of improper cultural practices. In some cases, the effect of poor
cultural practices may not be seen for years.
Of all the cultural practices, those associated with improper planting
have probably killed more landscape plants than anything else. For example,
a tree killed by root rot might never have been infected if it had been
placed in a planting hole with proper drainage. Many long-standing practices
associated with planting trees and shrubs are no longer recommended, because
recent studies have shown they are either an unnecessary expense or are
detrimental to plant growth and establishment.
You may purchase woody plants that have bare roots, are balled and burlapped,
or grown in containers. Transplants of bedding plants and vegetables are
usually grown in an organic medium, without soil, in flats, partitioned
plastic trays, connected mini-pots, or small, individual containers. Each
plant, however packaged, needs special attention at planting time if it
is to grow well and become a part of the landscape.
Bare-Root
Plants
These
are mostly deciduous plants which have been dug without attached soil.
Many shade trees, fruit trees, and flowering shrubs are sold in this manner.
It is essential to keep the root system moist until planting. This may
be accomplished by soaking the roots in water for 1 to 2 hours, but for
NO MORE THAN 6 hours; by wrapping them in moist burlap; or by temporarily
planting (heeling in) to planting depth in moist sawdust, bark or soil.
For best results, hold plants in the shade prior to planting. If the roots
dry out, the plant's chances for success will be greatly diminished. Before
planting, prune back any badly bruised, broken, or jagged roots to sound
wood with a clean cut. Girdling roots (major roots which cross over the
root system close to the trunk of the plant) may eventually strangle (girdle)
the stem. Remove these and any badly kinked roots at transplant time.
Dig the planting
hole deep enough so the plant, when set in the hole, will be at the level
it was in the nursery, or preferably, 1 to 2 inches higher (Fig. 1). The
diameter of the hole should allow spreading the roots without crowding
or bending them. Backfill using the native soil, which was dug out of
the hole.
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Adding organic amendments
to the backfill soil has been a source of controversy and is still found
in many planting and transplanting recommendations. Recent research at
a number of universities has shown that the addition of large amounts
of organic matter (peat moss, compost, ground bark, etc.) does not improve
plant growth and may actually have a detrimental effect. If the plant
is to be planted in a highly compacted soil, the addition of organic matter
to the planting hole may create a constantly wet condition, leading to
root rots, or it may create an ideal condition which the roots will never
leave. The greater the difference between the structure and texture of
the soil in the planting hole and that of the native soil, the greater
the possibility of problems.
Amending the
backfill soil for the planting hole with organic matter is not generally
conducive to good root growth. Amending the soil over a large area, such
as an entire bed or border, is beneficial for good root growth. This can
be accomplished by spreading 2 to 4 inches of organic matter (bark, sawdust,
compost) over the area to be planted. The organic matter should then be
worked into the soil to a depth of 6 or more inches. The deeper the organic
matter is incorporated the deeper will be root development. If a number
of ericacious plants (members of the heath family, such as heath, heather,
rhododendron, azaleas, etc.) are to be planted in close proximity to each
other, it would be advisable to use this system, especially in poor or
compacted mineral soils.
Construct a
basin around the periphery of the planting hole, so that water drains
away from the trunk but not away from the root system (Fig. 1). Water
the plant immediately to settle the soil and to eliminate any air pockets.
Keep the newly installed plant moist but not soggy wet. After the plant
is fully established, you may level the basin. Wrapping trunks of newly
planted trees may lessen the incidence of sun scald. It is critically
important that any fabric or material wrapped around the trunk be white
or very light in color, and that the material breathes or allows free
exchange of air through the material. Solid plastic type materials increase
the incidence of stem cankers and other diseases. Inspect the wrapping
every month or so to be certain it is not girdling (strangling) the stem.
Where drainage
is a problem, it may be advisable to construct a planting berm. This consists
of placing the plants above grade, either partially or totally above ground,
and filling in around the plant(s) with soil.
Staking at
this point will be necessary only if the plant cannot stand by itself.
Drive two wooden stakes into firm ground and tie the tree to the stakes
with nonchafing material (Fig. 2). Inspect frequently, and remove stakes
as soon as the root system is firmly anchored into the soil, usually one
growing season.
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Dig the planting hole deep enough so the top of the root ball (as it was
grown in the nursery) is at the soil line or preferably 1 to 2 inches
higher than the native soil level when the plant is placed in the hole
(Fig. 3). The planting hole diameter should be at least twice the diameter
of the root ball. When working with plants that have large root balls,
make the planting hole at least 1 foot in diameter larger than the root
ball diameter. REMOVE ALL STRINGS AND TWINE to eliminate the possibility
of girdling the roots or stems. This includes natural materials such as
binder twine and hay rope. Cut natural burlap away from the root ball
and fold it into the planting hole before backfilling. Synthetic materials
used for wrapping the root ball must be cut away and discarded after the
plant is placed in the planting hole and before backfilling. Backfill
using native soil. Construct a water basin, as suggested for bare-root
plants, and water the plant immediately after planting.
At times, the
soil in which the plant was grown differs greatly from the soil where
it will be transplanted. That is, the native soil may be quite sandy,
while the soil around the roots may be heavier (more clay). The interface
where the native lighter soil (sandy) and the heavier nursery soil meet
may pose a barrier to water movement. This generally means the root ball
will be constantly dry, leading to a dried out (desiccated) plant; or
the planting hole will be constantly wet, increasing the incidence of
root rots. If large differences in soil types exist, gently fork soil
away from the root system, exposing some of the roots (Dashed line, Fig.
3, number 5). Clean-cut any poorly cut, broken or damaged roots, and backfill
with native soil. You can avoid many future problems by placing roots
in contact with native soil so they must grow into the soil.
Container-Grown
Plants
Plants
grown in containers pose special planting problems. Nursery culture dictates
that the plants must be grown in soilless, or organic, medium. When you
select a container-grown plant, remove the container and look for fibrous
(small) roots growing to the edge of the container, which hold the soil
ball firmly together (Fig. 4). Spread the roots (Fig. 5) when transplanting.
Fig. 4. A good root system on a container-grown plant.
Fig. 5. Spreading the root system of a container-grown plant.
Dig the
planting hole deep enough so the bottom of the root ball rests on the
bottom of the hole when the top of the root mass is AT or slightly ABOVE
the soil line. The planting hole diameter should be dug as described for
balled and burlapped plants. Carefully spread the roots while backfilling
using native soil (Fig. 6). If the roots are woody, cut or slash them
using an old knife, spade, or shovel (Fig. 7). Make six to eight shallow
vertical cuts into the root ball, slashing through the exterior woody
roots. Use your fingers to loosen the cut roots and spread them away from
the container medium. Plant as described above and backfill using native
soil. Be sure to keep the roots spread as you fill the hole.
Fig. 6. Container-grown plant in planting hole.
Roots are spread and hole is partially backfilled. The planting hole should
be larger than the extent of the spread-out root system. Backfill using
the native soil. Spread the roots when backfilling
Fig. 7. Slashing
a plant root system with circling roots. Make six to eight vertical cuts
through the surface roots and spread cut root ends when planting. If roots
were not slashed before planting, this plant could develop severe girdling
roots similar to those in Fig. 11.

An alternative is
to "butterfly" the root ball once it is out of the container. This works
especially well when the circling roots are very woody. In this procedure,
drive a spade or shovel straight through the bottom third to half of the
root mass, creating two flaps of the bottom portion of the root ball (Fig.
8, 9). Make six to eight vertical cuts on the top portion of the root
ball, cutting through any circling roots.
Fig.
8. Butterflying a container-grown plant root system. Drive a spade or
shovel straight through the bottom half of the root system. Make six to
eight vertical cuts through the surface roots on the top half of the root
system.
Fig. 9. A butterflied
root system. Two flaps of roots were created by using a spade cut, as
in
Fig. 8. The top portion of the root system was cut by vertical knife
slashes.
When planting, spread
the two flaps butterfly fashion and place them in the planting hole (Fig.
10). The top of the root mass should be AT or, preferably, slightly ABOVE
the soil line. Backfill using native soil, making certain that the cut
roots are spread when adding backfill to the planting hole.
Spreading and
keeping flaps apart may be difficult. Working a stone, stick, or other
piece of wood, or even soil, between flaps to keep them separated may
be necessary.
Circling roots
of container-grown plants that are not corrected before planting will
continue to grow in a circle, eventually girdling themselves
(Figs. 11, 12). These circling and girdling roots will place severe physiological
and mechanical stresses on the plant. The plant will grow poorly, and
it may, as in the case of the pine tree in Fig. 11, eventually die. This
underground cause of plant stress is difficult, if not impossible, to
detect once the plant is in the soil.

Fig. 10. A container
plant butterflied and slashed. Cut roots at the top of the root system
are spread out into the backfill.
Fig. 11. The root system, at left, of a 12-year-old shore pine (Pinus
contorta) which died slowly after attaining a height of 5 feet. The roots
were not cut, spread or butterflied at the time of planting. The roots
eventually girdled themselves, killing the tree
Fig.
12. Bottom of pine in Fig. 11. The pine was planted in the ground from
a 1-gallon container. Twelve years later, its root system still fits a
1-gallon container
Field Potted Plants
These field-grown plants are dug either with bare roots or with soil,
and placed in containers. If the plants are in papier-mache' pots, remove
all or at least the top portion of the pot AFTER the plant is in the hole,
because these pots may restrict root growth into the native soil. Otherwise,
plant as a container-grown plant.
Bedding Plants, Vegetable Transplants, Small Perennial
Plants
Starter plants that help gardeners get the jump on the season usually
have a relatively small root mass. They are grown in a highly organic
medium in various types of containers, such as flats, trays, or peat pots.
At planting, remove plastic containers, and at least the top portion of
peat pots. When transplanting these plants, even the annual types, spread
the roots so they have good contact with the native mineral soil in which
the plant roots must grow. Keep the root system moist, but not soggy wet,
until the plants are well established.
Pruning the Top at Planting Time
Limit
this practice to:
1. Removal of dead
and diseased branches;
2. Removal
of rubbing, interfering, and wrongly placed branches; and
3. Pruning
to the desired shape. Begin to select the main skeletal branches (framework)
of trees at this point. Planning and shaping the plant when it is small
will avoid the need to prune much larger limbs later. Most landscape plants
do not require pruning at transplant.
It is NOT necessary
to remove one-fourth to one-third of the top unless the plant is in full
leaf or soft growth when it is dug.
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