Landscape design with plants university of kentucky

Pdf File 1,414.17 KByte, 16 Pages


Landscape Design with Plants:

Creating Outdoor Rooms

Janice A. Cervelli, former Professor, Landscape Architecture

The garden has been considered an essential element of a happy and full life since the beginning of time. As a result, landscape design has enjoyed equal stature with the major arts. The garden or landscape designer has held prominent positions in many cultures, including the courts of ancient Egypt, Renaissance Italy, Imperial France, China, and Japan. Master designers have generated many of the techniques of design through their own artistic talent, experience, and interpretation, as well as through strong sensitivity to the client, qualities of the site, and plants and materials used.

Today, landscape design is popular with the average homeowner. However, moving high-garden type art to the backyard context is difficult. When using plants in landscape design, the result is usually oversimplified and misinterpreted. Easy-to-follow "cookbook" landscape rules can be found in many popular landscape design magazines. Unfortunately, these publications do not discuss the overall three-dimensional structure of the design. Instead, they discuss the use of plants in terms of individual ornamental characteristics including form, color, and texture. In this type of approach to planting design, the most immediate visual attractions within the landscape are emphasized. One of the more important, basic, and classic aspects--the creation of three-dimensional outdoor space with plant walls, floors, and ceilings--is overlooked. That is unfortunate since this aspect of planting design can evoke the longestlasting overall impression within the outdoor experience.

This publication outlines the often-overlooked concept of landscape design with plants as architectural, engineering, and aesthetic tools that build an enjoyable outdoor environment. It is not intended to present any textbook rules for home landscaping nor discuss the most appropriate use of specific plant species. Such techniques of design are developed through one's own design experience or through viewing the design of others.

Plants as Architecture

Plants with respect to architecture can perform two roles. They can complement and reinforce the existing architecture of the house or structure, and they can create outdoor rooms.

Trees, shrubs, and ground covers can be used to emphasize the desirable architectural lines and masses of the house. The form and branching pattern of particular trees and shrubs can echo the vertical, horizontal, and diagonal roof and wall lines of a house. A pleasing, unified, and harmonious appearance can result (Figure 1).

Figure 1. Plants soften and filter light as well as blend with natural material.

Figure 2. Plant and house forms are in harmony.

Plants can be used to soften and balance harsh and awkward architectural angles, masses, and materials (Figure 2). Before actually purchasing and installing plants, an owner can plan the locations by assessing the desirable and undesirable qualities of the house. To do this, take a photograph of the front and back of your house, and sketch where plants are needed. Judge ultimate plant sizes at this time to ensure harmony with the house.

You can use plants to frame desirable views of your house. Remember, the best views are not always from straight on. Often, views to the entrance or windows are more interesting from an angle as one approaches from a drive or walkway (Figure 3). Selective framing allows the viewer to see only the best parts of the house and yard in a sequence that builds up curiosity.

Views of the house are important, but views from inside the house onto the front or backyard are even more so, and they merit consideration. A large shrub or medium-sized deciduous tree with lacy foliage and branching pattern can be used to provide enframement, a sense of scale, and an interesting foreground to the viewer from inside. In the winter, the branching pattern creates the same effect. Such a treatment can double your enjoyment of the landscape. Be careful to size and space the plant so that it does not overgrow and block windows.

The human eye has a tendency to follow the outline of the objects in the landscape. With this idea in mind, you can affect the apparent size of your house. By placing plants in increasing height away from the house corners, the horizontal lines are emphasized and its apparent length increases (Figure 4). This is especially helpful with boxy, two-story structures.

Figure 3. A grove of river birch is used to screen this house from the road. A sweeping drive, brought in from the left, focuses on the entrance of the house and discloses the rest of the house in a sequence.


Figure 4. By graduating plant sizes away from the house, the apparent size of boxy, two-story structures is increased.

The same arrangement in a scaled-down version can emphasize and lead the eye to the entrance or large picture window. Placing large, conical evergreen plantings on either side of the entrance often has the disastrous opposite effect of emphasizing the vertical lines, making the house appear taller and narrower and creating an uninviting, inhibiting appearance (Figure 5).

The proper placement of foundation plantings raises similar concerns. Evergreen foundation plants originally became popular for masking exposed foundation walls that were two to three feet thick and made of concrete block.

Most foundations on newer homes rarely expose more than 12 inches and can be masked with a ground cover. Older homes often have attractive stone foundations that should be emphasized, not masked. It is not always necessary to place great amounts of expensive evergreen plantings around the entire house.

It also is unnecessary to restrict the type of plant to evergreens such as yews or boxwood. Deciduous trees and shrubs are equally effective in complementing architecture. Deciduous plants can unify the architecture through a

Figure 5. Tall evergreens create an uninviting, inhibiting appearance to this entrance.

branching pattern. For example, horizontal house lines can be unified with a horizontal branching pattern. Deciduous plants also add an infinite variety of color and textural interest throughout the year. All of this is possible without distracting from the main feature, the house.

The growth habits and requirements of plants must be considered when they are used close to the house. When sizing a plant, take into consideration its mature height and width. Otherwise, an overgrown and crowded appearance that dwarfs and hides the house can result (Figure 6). Consult a number of information sources concerning plant growth. Check any special cultural and maintenance requirements of the plants such as soil type, moisture, sun exposure, and pesticides.

Figure 6. Plants that reach large sizes at maturity are often planted too closely to the house when small. When mature, they dominate and make the house look smaller.


Creating Outdoor Rooms The word architecture suggests the creation of spaces or

rooms for use by people. Inside the home, floors, walls, and ceilings are used to create different settings for a variety of activities ranging from gardening, handiwork, and cooking to formal entertaining, relaxation, and active sports. As a result, greenhouses, garages, utility rooms, kitchens, living rooms, dens, studios, and gyms are created.

The development of outdoor architecture or outdoor rooms utilizes the same elements as indoor architecture--floors, walls, and ceilings. The difference is that the elements of outdoor rooms are composed of plant materials that have a changing and dynamic, living quality. As time passes, the room will grow and mature and provide a varying seasonal display each year.

The second role of plants with respect to architecture is the creation of outdoor rooms. Before creating such rooms, determine what number, type, and size of spaces are needed. List what type of outdoor activities you expect to conduct. The list might include entertaining, cooking, gardening, reading, painting, sunning, or relaxing. You might also want space for children's play, active sports, storage, building projects, hobbies, and maintenance. Those activities that require a separate room must be noted, as well as those compatible activities that can be combined in one space, such as a workspace, storage, and parking area. Note the desired qualities of the space; that is, sun or shade, or hard or soft surfacing.

The creation of the various outdoor spaces can take one of two approaches. The most typical involves the new homeowner in landscaping a house that had previously received some landscaping and where outdoor spaces such as patios already exist. The approach is similar to that of redecorating an older home: the basic floor plan remains the same while the qualities of the floors, walls, and ceilings are changed with the addition of a new rug, wallpaper, paint, and furniture.

In landscaping, the designer should assess the condition of existing plants and views and determine what is to stay and what needs improvement. The result may be a simple cleaning-out, trimming, replanting of existing plantings, or planting of new foundation plantings. This approach may appear to be the most efficient. However, it fails to completely consider the new owner's special needs.

The construction of most new homes is also completed with little consideration of outdoor rooms. The front and rear yards are left as two large spaces with the side yards as small voids (Figure 7). Foundation plantings around the house, hedges along the property lines, and a few shade trees are often added by the first owners, but these additions will do little to encourage the most efficient spatial development in each yard.

Figure 7. A small side yard developed into an intimate strolling garden.

The second approach to room creation is the development of new outdoor rooms. Compare this to changing the actual floor plan of an old house by knocking out walls or building an entirely new structure. To develop a new room, assess the qualities of the existing site. Such qualities as views, topography, drainage, sun and wind exposure, and proximity to the house can suggest appropriate locations for activities. This type of assessment requires you as the designer to experience the site and characteristics on a frequent basis through all of the seasons. This activity will allow you to get a "feel" for the site and better match its qualities to your needs.

The simplest approach to locating new rooms is to begin by extending the house's interior rooms to the exterior. The outdoor room will take on a function and quality similar to the indoor room, producing a stronger relationship and harmony between the house and the landscape as well as increasing the apparent size of both. In this regard, the location of the house on the property and the floor plan of the house can help with strategic window and door locations overlooking good views. The small patios and decks added to new homes by developers are a positive step in this direction. Similarly, the entrance foyer or vestibule can be extended outward by expanding and developing


the front porch and area. Garage and driveway access can be extended to include an outdoor work and storage space. Define these rooms with plant or constructed walls, floors, and ceilings to avoid blending them into one large, characterless space.

Further development of each individual outdoor room should begin by determining whether the space is inwardly or outwardly oriented (Figure 8). Inwardly oriented space is characterized by either complete or nearly complete enclosure and a strong central focal point. Certain areas for sitting, sculpture displays, patios, and hot tubs require enclosure for purposes of privacy, quiet, and concentration. Rooms within rear yards will typically contain such activities and require this type of orientation.

Outwardly oriented rooms are enhanced by amenities outside the space such as good views and breezes. Certain spaces may require selective cutting of existing plants to provide good views or the installment of new plants to

frame the views. In most situations, activities taking place within the front yard are more public in nature and will require free visual access on and off the site and little enclosure; thus, it is outwardly oriented.

Once you have determined the orientation and function of the outdoor room, you can define the basic elements of architecture: floors, walls, and ceilings. The floor of an outdoor room can provide for continuity and a comfortable transition throughout a number of spaces. The floor can be created with pavement, lawn, ground cover, annuals and perennials, or low (1' to 3') shrubs.

As in any building, the activity to take place in a room will determine the size and material of the floor. Just as work and exercise areas or kitchen areas have a durable linoleum, tile, or wood floor, similar outdoor areas in the yard should be underlain by a durable lawn or even hard pavement. Likewise, as a formal living room or entertainment area calls for a more decorative, plush carpet, so should a formal outdoor garden, patio, or terrace. A variety of swathes and ribbons of ground covers, annuals, and perennials provide the highly decorative effects of an oriental rug if carefully planned to take full advantage of seasonal interest.

The type of plant materials used to define the outdoor room also will suggest the function. Lawn areas typically invite low volume, pedestrian traffic, and relaxation, while spots with ground covers, annuals and perennials, and low shrubs do not. You can create an activity-oriented room using a lawn area bordered by ground cover or low planting beds. Or a passive viewing garden can be created with more elaborate planting combinations and little or no lawn (Figure 9).

Figure 8 (top). Inwardly focused space. Figure 8 (bottom). Outwardly focused space.

Figure 9. An outside extension of the entrance foyer creates a viewing courtyard of elaborate plant combinations instead of lawn.


Download Pdf File