One aspect of a custom residential project that is often overlooked is landscape lighting. The home looks beautiful during the daylight hours, but when evening falls, the homeowners can't enjoy their investment. By offering a landscape lighting service, Landscape Contractors can increase their marketability along with their bottom line. The following article will serve as a refresher course on basic lighting techniques, fixture selection and light sources.

Illuminating landscape and architectural features has many benefits. Lighting enhances the beauty of any setting and extends viewing hours. Safety and security are increased. Functional light levels provided to facilitate pedestrian traffic or illuminate special features improve a project's image.

Unfortunately, the mystery surrounding lighting design can be intimidating. This article is intended to dispel myths and eliminate the fear of designing systems to illuminate landscape and architectural features. Including lighting in your plans is an excellent idea. The worst mistake you can make is not lighting your projects.

Lighting is both challenging and rewarding. Challenging because you have to balance differing amounts of art and science for each particular project. Rewarding because a well thought out and well executed design is magical. Having a basic working vocabulary of fixture types, lamp types and techniques is essential. It is also important to understand fundamental lighting principals. Knowledge will increase your comfort level.

Tools of the Trade:

Highlighting is an uplighting technique used to illuminate sculptures, boulders, plant materials and garden structures by placing two or more spot light fixtures at the base and angling them upward.

Light fixtures are the brushes and lamps are the paints used to create that art. Lighting fixtures simply house and protect the light source. Fixture choice is based on location restrictions as well as aiming and wattage requirements. Lamp choice determines the color, intensity and life of the light being projected. The pattern or spread of light is controlled by reflective surfaces built into the lamp or reflector supplied with the fixture. The total package is called a luminaire. Understanding how these tools work and which techniques to apply is where art blends with science.

Bullet fixtures are typically tapered or conical in shape and are designed for PAR or R style reflector lamps. Bullets are primarily used for uplighting. Since they offer good directional control and shielding; bullets are excellent for signs and columns and they are the tool of choice for creating "Moonlight" or other downlighting applications.

Well lights are one type of uplight and consist of a sealed fixture suspended inside an open cylinder or well sleeve. Because the lens and lamp are shielded from view, well lights are used on projects where glare is a primary concern.

When spotlights are placed behind plant material or a garden element and aimed at an adjacent wall to create a backdrop, it allows the viewer to enjoy the outline form of the object only. This technique is useful when trying to showcase very dense plant material that has interesting structure such as Pinus thunbergiana, Yucca varieties or Chamaerops humilis.

Direct burial uplights are totally sealed with the lens at grade level. They offer a great deal of design flexibility due to the wide selection of lamp and reflector types. Direct burial fixtures are rugged; so they are often used on commercial jobs. Glare can be controlled with internal louvers or external shields.

Pathway or border lights come in many styles all of which are designed to provide low level lighting. Decorative luminaires are used to accent flower beds, ground cover and shrubs while providing an architectural element. Bollards range from three to four feet in height, with the optical system located at the top. Bollards are usually available in round or square configurations and are used to illuminate large areas on commercial and public projects.

Floodlights provide wide, uniform light distribution horizontally and vertically and are used for wall washing, signage, and area lighting. They may be mounted on stanchions as uplights or on poles and walls as downlights.

Sources (Lamps)

Shadowing is similar to highlighting, but with the spot light in front of plant material that has a tall adjacent wall so that dramatic shadows are created as a backdrop. This method of lighting is an excellent choice for immature landscapes typical of new construction because it transforms a small plant and a plain wall into a high drama effect that moves with the wind.

Incandescent sources can be subdivided into Line Voltage (120V) and Low Voltage (12V) which are available in either standard incandescent or quartz/tungsten halogen versions. Electricity passing through a filament causes incandescent lamps to glow. However, tungsten filaments in quartz enclosures filled with halogen gas burn brighter, whiter, and longer than standard incandescent lamps. Typically 200 hours versus 750 hours. Low voltage requires a transformer to convert 120 volt power to 12 volts.

The scalloping effect is similar to silhouetting in that the fixture is positioned at the base of a wall behind the subject aiming up. The use of a non-reflector micro filament lamp combined with a clear lens creates a very sharp elliptical light pattern backdrop. Using this effect is an elegant way to enhance, straight, flat walls - especially if they have symmetrically shaped plant material such as Pyrus kawakamii or Dwarf Citrus positioned in the foreground.

Fluorescent lamps have an internal powder coating that glows when electricity passes through. A ballast is required to start and control the flow of electricity. Different types of powder coatings result in a variety of colors. Temperature effects the operation of fluorescent lamps. Average life is approximately 10,000 hours.

High Intensity Discharge (HID) lamps produce light when electricity passes through an arc tube containing pressurized gases. A ballast is required to start and control the flow of electricity. Mercury Vapor has an average life of 24,000 hours and produces a blue-green light which enhances the appearance of most plant materials. Metal halide, with an average life of 10-15,000 hours, produces a whiter light which gives a more natural appearance to most colors. High Pressure Sodium radiates a yellowish light, has an average life span of 24,000 hours, and is often used for architectural features.

Downlighting:

Downlighting involves lighting areas, objects or plant materials from above. "Moonlight" is created by aiming downlights through a tree's leaves and branches to produce soft, subtle shadow patterns on the ground. Shielded bullet fixtures are the proper tool. Floodlights and other unshielded fixtures create unwanted glare.

To create spectacular moonlight effects, fixtures should be placed as high in the tree as possible (generally ten feet higher than anyone is willing to climb). Aiming down through leaves and branches produces soft subtle shadow patterns on the ground. Placing fixtures higher in a tree lowers the light level on the ground. However, the coverage of each fixture is increased. Lights located deeper in a tree, toward its center produce softer effects because the light has to travel through more foliage. In contrast, fixtures placed lower in a tree cause higher light levels and offer a smaller area of coverage. Aiming down through holes in the foliage increases light levels and produces fewer shadows. Some designers place fixtures in the top of trees at the center and aim straight down while others aim down at an angle. Beams can be criss-crossed within trees to bring out texture. Fixtures aimed down out of tall trees onto shorter trees, shrubs, and flowers create wonderful patterns and simulate true "Moonlight". Aiming a fixture out the back of a tree will pull the viewer's eye past the tree and make the space seem larger.

When using multiple fixtures in a tree, placement is critical. Do not place fixtures too close together. This is unattractive during the day and is a source of unwanted glare at night. Do not aim fixtures above 45 degrees from vertical or glare may result. In general, shields should be placed between the source and the viewer. Shields can be rotated to achieve precise cut-off and light control. It is always a good policy to check the aim of each fixture. To save time on the job, fixtures can be energized and aimed during the day. However, fine tuning should always take place at night.

Recommendations for downlighting from trees in residential settings with moderate ambient light are shown in the following chart. Remember that bullet lights are also excellent uplighting tools.

Uplighting:

Accenting is a form of downlighting that draws attention to small garden details such as works of art, unique boulders or topiary. Trees, trellises and eaves make excellent platforms from which to downlight. By combining a remote light source with a very narrow beam pattern, an accent is embellished without an apparent source of light - further adding to the enchanting mood a well designed lighting system creates.

Uplighting is simply illuminating a tree or object from below. Since bright areas and shadows are the opposite of natural patterns generated by the sun and moon, uplighting is quite a dramatic effect. Dramatic uplighting effects can be achieved with bullets, floods, well lights, or direct burial fixtures. Although each fixture type can be used to generate equivalent effects, there are advantages to each type.

Choosing fixtures:

•Bullets are the least expensive types of uplights. Because they are mounted above grade they offer more aiming flexibility. Whenever dense ground cover is planned, choose bullet fixtures so that they will stick up out of the foliage. On the down side, bullets are more susceptible to damage by mowers or vandals than inground uplights.

When a project has walls or objects that have rugged surfaces, a series of fixtures placed 6-8" from the base will create a high contrast "black and white" effect. Graze lighting is perfect for high relief stucco or natural stonewalls; however, it can also be used to accentuate the unique bark texture of plants and trees.

•Floodlights can be used to uplight very large trees. However, their large size can be obtrusive. Barn doors or glare shields should be used on floodlights to prevent unwanted glare.

•Well lights offer the most unobtrusive form of uplight. The source is shielded from direct view because it is recessed in the "well sleeve" and shielded by the louver grill. Well lights are often used on the residential projects where glare is the primary concern. If soft and subtle uplight is what you seek, pick well lights. However, be prepared to follow a formal maintenance program. Leaves, insects and debris have a habit of falling into the opening of the fixture and they must be removed and the fixture cleaned regularly.

•Direct burial fixtures require less upkeep than well lights and should be used on commercial projects where maintenance is a concern.

Techniques:

•Using two uplights per tree will add depth and texture to the scene. With a properly spaced row of trees placing a fixture between each tree and at both ends of the row will create the effect of having two lights per tree.

•Fixtures located behind a tree will cause a backlit effect if they are aimed toward the tree and the viewer.

•Fixtures placed behind a tree will cause a silhouette effect if they are aimed at a reflective surface behind the tree. The location of the primary viewing area or direction of travel should be considered when locating fixtures. Uplights should be located 1/3 to 1/2 distance from the trunk of the tree to the outside edge of the canopy or "drip-line". Placing uplights less than three feet from the trunk will cause a hot spot at the base of the tree.

To illuminate the lion-head fountain, the lighting designer mounted a 12-volt downlight in a trellis (not pictured). The 20-watt lamp was aimed at a 35 degree angle to accent the lion's head. Lamps in the planter bed are 14 watt PAR lamps and the luminaire uplighting the tree is a 20 watt Hadco fixture set at a 60 degree beam spread.

Along with fixture placement, lamp type, wattage, and beam spread help determine light level. Desired light level depends on the type of project, design intentions, and ambient light level. Recommendations for uplighting trees in residential settings with moderate ambient light are shown in the chart above. Remember, uplights are excellent for illuminating columns, statues and special features.

To illuminate walls, the lighting designer can either opt to use floodlights or inground uplights. Each option has a unique set of specifications that need to be followed.

If your goal is uniform, scallop free illumination, using a floodlight is the best choice. Simply use the following rules of thumb:

•Aiming Points - For uniformity from top to bottom, aim the fixture two thirds up the vertical surface. If a wall is twenty one feet tall, aim at a point fourteen feet up the wall.

•Setback - Setback is frequently limited. However, if possible fixtures should be setback from the wall the same distance you are aiming up the wall. For the example above, the aiming point is fourteen feet above grade so the setback distance is also fourteen feet. The minimum setback distance is one-quarter the height of the wall. Regardless of the setback distance, spacing should be twice the setback.

•Spacing - For optimum uniformity fixtures should be spaced at a distance of two times the setback distance. Fixtures setback fourteen feet from the wall should be spaced twenty-eight feet apart. This causes the beams to overlap and produces uniform light levels. If uniformity is less of an issue than budget, fixture spacing can be stretched up to four or five times the setback distance.

Since inground uplights are unobtrusive, they are often chosen to illuminate decorative elements, signs and walls. However, due to differences in location and aiming angles, inground lights will not provide the same uniformity as floodlights.

To design attractive jobs simply use the following rules of thumb:

•Setback - Placing fixtures too close to a wall will result in hotspots at the base of the wall. Placing fixtures too far from a wall will cause shadows or scallops at the base of the wall. Most inground fixtures perform best when placed three to four feet from the wall. However, greater setbacks are required for taller walls.

•Spacing - Placing fixtures too far apart results in larger scallops at the base of the wall. For most applications, a spacing of three to four time the setback results in an acceptable appearance.