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Color, line, form, texture and scale are tools which are used in
combinations to adjust design principles. Design principles include
unity, balance, transition, focalization, proportion, rhythm,
repetition and simplicity. All these principles interact to yield the
intended design.
Unity
is obtained by the effective use of components in a design
to express a main idea through consistent style. Unity is emphasized by
consistency of character between units in the landscape. Use of
elements to express a specific theme within units creates harmony.
Unity can be achieved by using mass planting and repetition.
Unity means that all parts of the composition or
landscape go together;
they fit. A natural feeling evolves when each activity area belongs to
and blends with the entire landscape. Everything selected for a
landscape must complement the central scheme and must, above all, serve
some functional purpose.
Balance
in design refers to the equilibrium or equality of visual attraction ( Figure 6 ).
Symmetrical balance is achieved when one side of the design is a
mirror image of the other side. There is a distinct dividing line
between the two sides. Equal lines, forms, textures or colors are on
each side of a symmetrical design.
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Figure 6.
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Asymmetrical balance uses different forms, colors and textures to
obtain balance of visual attraction. These opposing compositions on
either side of the central axis create equal attraction. For example,
mass may be opposed by color or linear dimension by height.
The landscape designer must skillfully
manipulate the design elements
to create asymmetrical balance. The central axis must be predetermined
and then developed by the elements of art and other principles of
design discussed in this publication.
Transition
is gradual change. Transition in color can be
illustrated by the radial sequence on the color wheel (monochromatic
color scheme) previously discussed. Transition can be obtained by the
arrangement of objects with varying textures, forms, or sizes in a
logical sequential order. For example, coarse to medium to fine
textures, round to oval to linear structural forms, or cylindrical to
globular to prostrate plants. An unlimited number of schemes exist by
combining elements of various size, form, texture and color to create
transition ( Figure
7
). Remember, transition refers to the 3-dimensional perspective of
composition, not just the flat or facial view.
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Figure 7.
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It is possible to use transition to extend visual dimensions beyond
actual dimensions. For example, radical lines in the private area of
the landscape can be used to enframe and/or focalize a lake scene.
Transition of plant materials along these lines can make the scene
become a part of the landscape ( Figure 8
). Transition from taller to shorter plants with textural changes from
coarse to fine along focal lines emphasizes the beauty of a lake scene.
Transition from shorter to taller plants and from fine to coarse
textures would enframe the scene and make it appear closer, like a
painting on a wall. Generally, transition assists in the gradual
movement of a viewer's eye to the design and within it.
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Figure 8.
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Proportion
refers to the size of parts of the design in relation
to each other and to the design as a whole. One large towering oak may
compliment an office building but would probably dwarf a single story
residence (
Figure 9
). A three-foot pool would be lost in a large open lawn but would fit
beautifully into a small private area. And of course, a colossal
fountain would dominate a private garden but could enhance a large city
plaza.
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Figure 9.
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Proportion in landscape design usually relates to people and their
activities. The desired size relationships of components in a design
should pose little problem for the designer who considers this
principle routinely in systematic thought processes.
Rhythm
is achieved when the elements of a design create a
feeling of motion which leads the viewer's eye through or even beyond
the designed area. Tools like color schemes, line and form can be
repeated to attain rhythm in landscape design. Rhythm reduces confusion
in the design.
Focalization
involves the leading of visual observation toward a
feature by placement of this feature at the vanishing point between
radial or approaching lines. Straight radial lines as in
Figure 10 create a strong focalization when compared to
curved lines. The
viewer's eye is quickly forced along straight lines to a focal point.
Generally, weaker or flowing lines of focalization are desirable in the
residential landscape. Transition of plants or other objects along
these lines can strengthen or weaken the focalization. Curved lines are
stronger when curved toward each other than when curved outward.
Indirect focalization is created by lines curved in the same direction.
Focalization can be adjusted by plant materials along the lines to
create symmetrical or asymmetrical focalization. Asymmetrical
focalization is indirect while symmetrical focalization is more direct,
creating stronger focalization.
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Figure 10.
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Since focalization can be used to direct attention to a point, traffic
in an area is usually directed to that point. Therefore, focalization
could be used to direct traffic in a garden area. Guidance of view
toward features of commercial, aesthetic or cultural value may attract
the eye of the unaware without conscious effort.
Repetition
refers to the repeated use of features like plants
with identical shape, line, form, texture and/or color. Too much
repetition creates monotony but when used effectively can lead to
rhythm, focalization or emphasis. Unity can be achieved better by no
other means than repetition. Think of repetition as not having too much
variety in the design which creates a cluttered or busy appearance.
Simplicity
goes hand-in-hand with repetition and can be achieved
by elimination of unnecessary detail. Too much variety or detail
creates confusion of perception. Simplicity is the reduction of a
design to its simplest, functional form, which avoids unnecessary cost
and maintenance.
STEPS IN DEVELOPING A LANDSCAPE DESIGN
The benefits of an organized system in developing a landscape design
are tremendous. As with most endeavors, the level of efficiency
relative to time input is greatly increased with an organized approach.
The game plan for the landscape designer should follow a sequence such
as the one presented here:
Steps In Design
- Develop a plot plan.
- Conduct a site analysis.
- Assess family needs and desires.
- Locate activity areas.
- Design activity areas.
- Plant selection and placement.
Develop a Plot Plan
It is difficult to visualize certain aspects of design without putting
it to scale on paper. The designer should think with drawings or
sketches and make the mistakes on paper not on the landscape site. The
plot plan should consist of 1) accurate house placement on the lot, 2)
accurate lot and house dimensions with window and door placement and 3)
existing driveways and/or walks. It saves a lot of time if the customer
has an accurate plat of the house and lot and a house floor plan with
outside dimensions. These plans maybe secured from the builder,
developer or county or city property records. Although the floor plan
scale will probably be different from the scale you use, it will still
be easier to convert the scale than to physically measure the house,
lot, etc.
Once the house position on the lot has been
determined, this should be
drawn to a predetermined scale on tracing paper placed over grid paper.
Commonly, 1 inch equals 5 feet or 1 inch equals 10 feet, but you may
choose another scale based upon your drawing equipment and project
dimensions. Recommended drawing equipment includes: drafting pencils,
T-square, scaled rulers, triangle, art gum eraser, drafting tape, grid
paper (8 or 10 squares to the inch) and tracing or drafting paper. The
designer must have a firm, steady working surface.
Conduct a Site Analysis
A complete survey of the customer's property is essential. The plot
plan will assist you in organizing the information from the site
analysis. A thorough site analysis can save you time and money.
Existing vegetation, natural factors and features, views, noise levels,
utility placement, easements/setback lines and primary architectural
features of the house should be noted.
Existing
plants should be
examined. Tree condition and placement
should be recorded. Trees on adjoining property that would affect shade
patterns on the customer's lot should also be surveyed. This
information is essential to designers, especially since it is their
responsibility to blend this home into the natural or existing setting,
or to create a setting to be functional and to complement the
structure. Shrubs, groundcovers and grasses should also be examined as
to their condition and potential use.
The landscape horticulturalist may also be
involved in protecting
existing vegetation during construction. It may be desirable to block
vehicular traffic from areas close to valuable trees.
Natural
factors and features of a
landscape include house
orientation, land form, soil conditions, rainfall distribution,
seasonal wind pattern and micro-climatic conditions. House orientation
affects the exposure of various portions of the house to the sun (
Figure 11
). This knowledge is essential so the designer can provide shade in
important spots and locate activity areas appropriately. For example, a
southeastern exposure is generally the most comfortable spot year-round
while a western slope will be hot in the summer and cold in the winter.
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Figure 11.
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Land
form refers to slope or
land elevation changes. It
determines surface water drainage patterns and is essential knowledge
for the landscape horticulturalist in developing functional and
aesthetically pleasing landscapes.
Soil characteristics will
determine selection and placement of plants. Soil pH, nutrient and
waterholding capacity and drainage should be considered. Native
fertility levels and soil characteristics may be indicated by existing
vegetation. Turkey oaks on the property usually indicate dry, infertile
soil. Native cypress trees usually indicate poorly drained soils exist
or did exist in that area.
Rainfall distribution can be determined on a
regional basis. Periods of
heavy rainfall can magnify the problems of shallow soils or a hardpan
resulting in unwanted standing water. Sometimes these conditions may
require the engineering of drainage modifications by some type of tiles
or pipe. Often the conditions simply require careful plant selection.
Predominate wind directions differ with the area
of the state, the
season and the time of day. Where the wind direction differs in summer
and winter, plantings can be arranged to block the cold winter winds
from a patio and direct summer breezes into this same area (
Figure 12
). While conducting the site analysis, be sure to look for existing
wind breaks provided by plants and structures on the property or on
adjacent property.
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Figure 12.
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All of these factors interact to create micro-climates. This means that
the conditions in a isolated spot may differ considerably from the
conditions in another area of the landscape. The designer must consider
those variations in order to "fine-tune" the landscape plan and plant
selection.
Views should be identified that are to be
preserved or accented.
Likewise, less desirable views must be considered so screening can be
planned. Views and activities 30 feet (9 m) or so from the property
line must be surveyed. During the site analysis, views should be
observed from inside the house to outside and from outside to inside
the house (
Figure 13
). Observe the neighbors' property from positions on the customer's lot
and view the customer's property from the neighbors' lots if possible.
The house should also be observed at multiple angles from the street.
Pictures from an instant camera can be helpful in reminding the
designer of specific views when sitting back at the drawing table.
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Figure 13.
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Surrounding distractions must be identified. You may need to question
neighbors or the property owner about these factors. Record a noise
source like roads, factories, saw mills, etc. and plot the direction
and distance of the source. The time of day for peak noise levels can
be important as well. It may be necessary to return to the site during
such a period. Other distractions could include glare or odors.
Utility lines may be on poles or underground.
Locate the position of
these on the plot plan. Also locate the electrical meter on the house,
the air-conditioner unit and water outlets. Consider the position of
television and telephone cables, water lines and sewage lines, or a
septic tank and field line. Television cable companies and the
telephone company will usually locate their service lines accurately.
However, these services must be requested in advance.
Architectural
style of the house is
of primary importance.
Specific details of interest must be identified during the site
analysis. Things like the height of windows, the height of house
corners from the ground and overhang widths should be considered. Is
the house guttered or should it be? If so, locate the outlets. Notice
major traffic problems so proper access and movement can be provided.
Assess Family Needs
A landscape should be an outdoor extension of indoor living areas. It
should be functional and provide space for family activities. Before
the designer can create such an environment, knowledge of certain
family characteristics is essential.
The questions used in the form
at the end can be among those asked of the customer.
Locate Activity Areas
Once the family needs have been determined, areas for these activities
must be located on the property. Their placement should be considered
in terms of the house plan and in relation to other activities in and
adjacent to the property. These activity areas could include a public
area, entrance, living area, quiet zone, service and work area, or
vegetable or cut-flower garden plot.
These areas should be defined on the plot plan
or maybe on a piece of
tracing paper laid over the plot plan. Actually sketch the outline of
these areas (
Figure 14
). Be sure to include all needed activity areas and draw them to scale
and to the size necessary to accommodate the activity, yet still fit
within the property lines.
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Figure 14.
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Two major considerations for the placement of areas must be emphasized.
1) Place outdoor areas in relation to indoor activity areas (
Figure 14
). The outdoor living or entertaining area should be an extension of
the family or living room in the house. The service area and work area
may be an extension of the laundry room, kitchen or garage. 2) Arrange
areas relative to the activities in each and activities on adjoining
property. For example, do not position the children's play area beside
the quiet zone. Always leave a clear view to the children's play area
from some identified observation point like the kitchen window.
Design Activity Areas
A systematic approach should be taken in designing activity areas.
First, determine the objectives of the design and establish the general
type of plan -- formal or natural. Plan for structural needs, consider
land form modifications, determine traffic flow, develop bed form and
then specify plant materials.
Structural needs should be considered first. If
a storage building is
needed, a level spot and access must be planned. Required access may
mean a path or limited vehicular access to haul in firewood, etc.
Land form information derived from the site
analysis can be used now.
Do surface water drainage problems exist? If so, determine how to
correct them. Engineering and legal considerations are involved in
major surface water drainage problems. Seemingly simple solutions may
affect someone else's surface drainage. Consider grassed waterways,
paved waterways or possibly drainage tiles. Drainage problems may not
exist but land form modifications could be used to create interest, or
help block undesirable views or noise. Care should be taken not to
create surface water drainage problems with land form modifications.
Existing land form may have slopes which will
erode. Existing slope or
steepness will determine what actions should be taken. Ground covers
may be the answer for long, gentle slopes while terraces with railroad
ties or blocks may solve the problem of a short, steep bank. Grass
should not be put on slopes greater than 1:6 (1 foot of rise per 6 feet
of run) because of maintenance safety. Other ground cover materials
will probably hold a 1:2 or 1:3 slope. Bark mulch should not be placed
on a slope greater than 1:10.
Bed form, traffic flow and plant selection and
placement utilize art
elements and design principles previously discussed. These can best be
covered as the development of specific areas is discussed.
Public
Area. The
public area is the portion of the
residential landscape the public sees and uses. The current trend
toward smaller residential lots encourages the development of some of
the front yard for family living. The public area contains the
driveway, parking, walks, open space and entrance area. The purpose of
the public area is to enhance the home, provide comfortable access and
lead the visitor to the entrance.
Foundation planting is not all of landscaping
but can be a vital part
of functional landscape design. Too often foundation planting is
overdone and left to stand along. History reveals that foundation
plantings were used to block the view of raised foundations and to slow
cold air movement under the house (
Figure 15
). Although these needs do not often exist today, some
landscapers and
homeowners think it is a must to cover every linear foot of the
foundation with plants.
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Figure 15.
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The objectives of foundation planting are to focalize the main
entrance, compliment the architectural style of the house and to break
long continuous lines of the house and blend it into the surroundings.
The designer should avoid competing elements which detract from the
main entrance and the house in general. An isolated bed in the middle
of open lawn area is one of these competing elements. Plants should be
selected which can easily be maintained to proper scale with the house.
This is probably the most common failure of foundation plantings.
A general rule of thumb is that the height of
plants in the foundation
planting should not exceed two-thirds the height of the wall at house
corners (
Figure 16
). Generally, plant height should not exceed the height of a line
extending from the doorway to this imaginary point at the house corner.
This does not mean every house should have plantings this high.
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Figure 16.
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Balance in landscape design is not always necessary. Imbalance may be
used with architectural features of some houses to create desirable,
interesting effects. However, when balance is suggested, it should be
achieved.
Symmetrical balance has been overdone in
residential landscape design. This approach seems formal and monotonous
( Figure 17
). Asymmetrical balance is often more desirable for residential
landscapes as balance is created without monotony. Size is balance by
mass and texture in this example. Architectural style may dictate the
use of symmetry or asymmetry. Driveways, parking and walks must be
functional. They must be positioned to provide easy access from points
of entry onto the property to the entrance of the house. Too often
walks are placed from the street to the front door with no
consideration of access from the driveway to the front door. Many times
a walk dividing the front yard is not necessary and may detract from
the house.
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Figure 17.
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Walk and driveway surfaces should be selected based on traffic demands.
Low traffic walks and driveways may be surfaced with less expensive
materials such as bark or gravel, but walks and driveways with high
traffic demands should have a hard surface.
Walks accommodating two people abreast should be
at least 4 feet (1.2m) wide (
Figure 18 ). Walks for one person should be at least 30
inches (74cm) wide
(Figure 18). A straight driveway for one car should be at least 8 feet
(2.4m) wide while 14 feet (4.3m) is required for two cars side-by-side.
Circle drives should have a minimum inside radius of 18 feet (5.5m) and
an outside radius of 32 feet (9.8m) with a surface width of 14 feet
(4.3m). Steps should be designed with human comfort as the top
priority. Generally, a taller step, one with greater rise, should have
a longer tread area. A handy rule of thumb states that twice the rise
in inches plus the tread should equal 26 or 27 ( Figure 19
). Ramps for wheelchair access are necessary or desired in some
residential landscapes. The average wheelchair user can negotiate a 5
percent gradient independently and the minimum width is 3 feet (90cm).
The bottom and top approach to a ramp should be clear and level for a
distance of at least 5 feet (1.5cm).
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Figure 18.
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Figure 19.
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Driveways must be wide enough at the street to allow cars to merge
easily into the flow of traffic. The higher the average speed of the
street traffic the wider the mouth of the drive should be.
The view of street traffic from the driveway
entrance should not be
blocked. Large plants placed along the driveway entrance create a
dangerous situation. Plants on the outside of a curve in a driveway or
highway aid the driver by giving definition to the traffic flow. Make
sure such a planting blends into the total design. A plant screen on
the inside of a curve in a driveway or highway is hazardous because it
blocks the driver's view of the road ahead.
Trees can be used in the public area to soften
lines, provide shade and enframe the house (
Figure 20
). Also trees placed in the backyard can provide an excellent
background for the house as viewed from the street. Vertical lines of
many houses can be effectively softened by a small tree planted in
conjunction with other plants at a corner. Tree shape is very
important. A low-branched, rounded tree softens this line while a
slender upright tree only accents the line. Trees with a lot of exposed
trunk, like a sabal palm, will also accent and not soften these
vertical lines.
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Figure 20.
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A long low house (ranch style) can be made to appear taller in relation
to its length by proper placement of plant materials ( Figure 21
). Larger trees planted as a background break the horizontal roof line.
Smaller trees spaced a few feet from the ends or corners of the house
would also help the house seem taller in relation to its length.
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Figure 21.
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A tall slender house seems longer when few or no trees are placed in
the background but medium-sized, rounded trees are positioned on either
side of the house (
Figure 21
). Plants placed near these trees should be shorter and decrease in
height the farther from the house they are positioned. This planting
design effectively created a sloping line to replace the strong
vertical line of the house. The house then appears longer in relation
to its height.
Trees positioned for shade must be carefully
located. The designer must
learn what area needs shade, and during what time of the day and what
seasons the shade is needed. This information will determine where to
plant the trees relative to sun angle, sun direction and areas to be
shaded.
A moderate amount of open area in the front yard
can create the feeling
of a large expansive area that allows the observer's eye to move from
the street to the planted areas. The planted areas can then direct the
observer's eye to the appropriate place. Some family game activities
need not be in the private living area and can be accommodated by open
portions of the public area.
Entrance.
The entrance should
be an area of transition
between outdoors and indoors. Considerable detail should be given to
the planning and maintenance of this area. This is true because a
visitor is close to this area and moving slowly or actually standing
still. Therefore there is time to view this area and a favorable
impression can be developed before a person enters the house.
Plantings in the public area should focus
attention to the entrance.
This means there should be no doubt in the visitor's mind where to
enter the house. If the house is approached commonly from more than one
direction, the focalization of the entrance form these different
perspectives must be considered. This focalization is achieved through
repetition of plant masses (
Figure 22 ). Transition of plant form, color and texture
and the bed lines can
help direct attention.
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Figure 22.
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Focusing attention toward the entrance is not the same as accenting the
entrance or access area. Plantings, like liriope, along both sides of a
walk in the open lawn only draws attention to or accents the walk.
These do not direct attention to the entrance, but actually distract
the observer's attention from the entrance area to the walk itself.
There should be a feeling of intimacy or comfort
with limited exposure
when a person is standing in the entrance area. Security and the need
to focus the entrance may dictate the extent of exposure in this area.
In a outdoor public area for a larger home, an extensive entrance
garden may be appropriate. Be careful to keep this area in scale with
the house and its surroundings. These areas are sometimes called "good
night" areas, because they provide an effective transition between the
indoors and the vehicle parking outside.
Living
area. Elements
in the living area, primarily the
backyard, depend upon the desires and needs of the family. These
desires and needs were determined during the interview outlined
previously. This area must be clearly organized to avoid wasted space.
Living area space must be organized based on the activities to be
included there. Consideration is given to the house design, land form
and house orientation as they relate to space organization.
Private area(s) are usually a part of the living
area. A private area
may be for reading and meditation as an extension of the master bedroom
or it could be an area for small group conversation as an extension of
the living room. A private area may be placed close to the house or in
an isolated corner of the landscape.
Space and equipment for children's play are
required in many
landscapes. The play area should be an integral part of the landscape.
Enclosure of this area may be required, based on age of children, size
of area and activities on adjacent property. The permanency of the play
area depends upon the ages of the children and family plans. If the
children are 8 to 10 and no other children are expected, the area may
be temporary and plans for future modification should be suggested to
the customer.
The children's play area may require some open
space. This space may
also serve for adult entertaining. Planning for multi-use space of this
sort can lead to high space utilization and efficiency.
It is often important to provide a degree of
privacy in the living
area. Fencing, walls or plants used for this purpose can also block
views, enhance views and direct or block prevailing winds.
Structural features in the living area could
include a patio, deck,
terrace, water feature and/or garden and workshop. A patio used as an
extension of the family room should be at least 12 feet by 15 feet (4m
by 5m). The selection of surface material is based on land slope,
expected use rate, style of the house and the amount of funds
available. Raised wooden decks are suited for sloping land and are
cooled by air flow beneath them. Brick and sand is less expensive than
brick and cement and if installed properly can be quite durable.
Stained concrete and concrete with an aggregate surface are also
alternative surfaces for patios.
A water feature could be a swimming pool, spa,
or a simple reflection
pool. Moving water creates a secure, relaxed feeling in a private area
and is often overlooked for this use. Expense of these items is often
the limiting factor.
The designer should be concerned with traffic
flow and circulation in
the living area. Each unit in this area should be a part of the whole
and contribute to the overall circulation pattern. This is especially
true in the areas where entertaining is planned. Areas of limited
access, like service areas, may not be a part of this circulation
pattern. Circulation refers to the movement of people's eyes and then
their bodies through a specific pattern in the landscape. For example,
a quiet sitting area located in the back corner of the lot is hidden
from view of the patio (
Figure 23
). Proper bed arrangement and plant selection will lead the observer to
one focalization point in the landscape. The person, now located at
that point sees another focalization point and so on until the sitting
area is seen. This systematic method moves people from one point to
another until the desired circulation and traffic flow patterns are
created. Walt Disney World is a working example of planned traffic flow
by this technique.
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Figure 23.
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Service
Area. The
outdoor service area is an extension of
the indoor service rooms like the kitchen, utility room and/or garage.
It is a part of the overall design, but is usually screened from most
parts of the living and public areas. Access from the house and from
other parts of the landscape will be necessary. Sometimes vehicular
access is desired. The family interview previously discussed, will
determine what must be included in this area. The amount of space
available and number and type of activities to be included will
determine the required size.
A service area could include tool storage, work
space, clothesline,
garden supplies storage, trash cans, firewood and a vegetable or
cut-flower garden. It is possible to have service functions in two or
more locations in the landscape.
Definition
and Separation of Areas.
Once the activity
areas have been located and ideas for development of these areas have
been formulated, the need for separation of these areas is often
apparent. Space can be the medium for separation when working with a
larger piece of property. Most often some other type of separation is
required due to the number of separate activities planned in a small
area. Sometimes it is only necessary to define space with a rail fence,
etc., rather than providing a complete screen or barrier. Spaces can
also be separated by changes in elevation. Planters can separate areas
and can be a very attractive means of defining space.
A visual screen from one direction without being
a physical barrier
fits the bill for some situations. Groupings of plants can be
positioned to give a visual block in one direction while allowing air
flow into the activity area as previously shown in
Figure 12 .
The required height of a screen depends upon the
elevation of the view
to be screened. A screen for privacy from the neighbor's two story
window will require a taller screen than one for blocking the view of a
neighbor down in the valley (
Figure 24
). Generally, a screen should be placed as close as possible to the
item to be screened.
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Figure 24.
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Plant materials provide an inexpensive screen with color and interest.
They generally require more space than fences and it takes time for
them to grow to mature size. Fences provide an immediate screen, occupy
little space and are quite expensive. The budget and available space
will be the determining factors in this decision.
Screens can be combinations of raised land form,
ground covers, small
shrubs, large shrubs, and trees to give a complete or strong barrier.
This combined planting is especially suited for noise abatement where
the lot adjoins a busy public street (
Figure 25
).
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Figure 25.
|
Plant Selection and Placement
Plant selection is the last step in the design process. Up until this
point, plant form, texture, color and size have been visualized, but
now a name must be assigned to each plant. Plants are selected on the
basis of climatic adaptability to the microclimate of the location,
plant architecture and availability.
No matter how well a plant meets the physical
characteristics for a
location, if it is not adaptable to the conditions there, it will fail.
These microclimate conditions include sun intensity and duration, soil
conditions, rainfall, air circulation and temperature. Some plants
perform better in partial or full shade than in full sun. The length of
daily exposure to a particular light level also influences plant
responses. Soil pH, soluble salts level and drainage properties
influence plant adaptability greatly. Plants can be selected to
tolerate varied soil conditions, but the designer must have a working
knowledge of available plant materials.
Some locations in a landscape may be
characterized by little or no air
movement. Plants susceptible to mites, scales and other insects will
usually be attacked more severely in areas with poor air circulation.
Also locations in the landscape differ as to the maximum or minimum
temperatures and daily fluctuation between these extremes. Plants can
be selected to tolerate one or more of these conditions.
Plant architecture consists of form, size,
texture and color. Plant
form is classified as columnar, upright, spreading, broad spreading and
prostrate. Plants should be selected on the basis of their mature size
or a size at which they can be maintained easily. Texture is referred
to as fine, medium or coarse. It is determined by branching habit, leaf
size and shape, leaf arrangement, leaf color and leaf surface texture
(dull or glossy). Plant color is determined by the foliage, flowers
and/or fruits. Knowledge of a plant's seasonal color variations is
essential.
Landscape designers must also be aware of insect
and disease problems
for plants they expect to include in a plan. Desirable plants are those
resistant to or tolerant of pests like mites, scale, nematodes, borers,
root rots, powdery mildew, wilts, galls, blights, and leaf spots.
Plants in some locations must be tolerant of human abuse, air pollution
and animals.
Usually, plants should be spaced with
consideration to their mature
size. Plants in large areas or groups are generally spaced to cover an
area in 3 to 5 years. Plants should be spaced far enough from the house
so that there is adequate air circulation near the house. Generally,
space plants from the house by at least the distance of the plant
radius at maturity. Spacing plants too close to the house is a common
mistake.
Minimal
Maintenance Considerations.
Maintenance cannot be
avoided, but it can be minimized. Even the perfectly designed and
installed landscape will fail if maintenance fails. However, many
maintenance problems are designed into landscapes.
Complex designs usually require more
maintenance. Simplicity can be
achieved by avoiding unnecessary detail. Limit the number of plant
species and create well-defined planted areas by not scattering plants
throughout open areas.
Design the appropriate size of maintained area
and arrange plants in
groups of like species to create a mass effect. Tree beds can eliminate
trimming, reduce lawn mower damage to tree trunks and increase the
speed of mowing. Edging of beds creates a sharp clean line and reduces
maintenance requirements.
Make sure bed
lines encompassing a lawn area meet at angles greater
than 90 degrees. Walk, driveway and patio surfaces that are in grassed
areas should be above the ground level. Avoid improper plant selection,
spacing and installation that can cause maintenance headaches.
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