Transcript Chapter_8_Hort

Chapter 8
The Interior Use of Plants
Evidence of the use of potted plants is found in
ancient Chinese artifacts, on the walls of tombs
of the Egyptian pharaoh, and the ruins of
Pompeii.
 Containers of ornamentals adorned the palaces
of European nobility for centuries and filled the
parlors of middle-class Victorians and Americans
more recently.
 Potted foliage plants or house plants have had
their place in homes for many years.
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An unsatisfactory outcome is predictable
when architects and interior decorators try
to work with plant material whose
qualities and maintenance requirements
are unknown.
 The term interior plantscaping comes from
the demand for maintaining plants
indoors. It is a variation on the term
landscaping.
 For now, the term interior plantscaping
will be used to describe the work.
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Tropical foliage plants have proven to be the
most successful indoor plants because they do
not require the period of cool temperature
dormancy that often makes temperate zone
plants unsatisfactory.
 As a profession, interior plantscaping deals with
the design, installation, and maintenance of
plants in interior locations.
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Five things plants must adjust to when used
indoors:
– A drastic reduction in the quality and intensity of the
light
– Reduction and constriction of the plant’s root system
– The replacement of natural rainfall by dependency on
humans for correct watering
– A reduction in nutrient requirements and a potential
for buildup of soluble salts (fertilizers)
– A lack of air movement and rainfall, allowing dust to
accumulate on the leaves, often plugging stomata
and reducing photosynthesis
– Potential damage by air conditioners, central heating
system, cleaning chemicals, water additives, and
other irritants.
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To understand the lighting requirements of a
plant you must ask:
– How much light do interior plantings need?
– What kind of light do they need?
– What sources of light exist indoors?
No matter how many windows and skylights are
designed into a home or office
building, the light intensity inside
will never equal that outside.
 Light intensity is expressed in
units of lux or footcandle.
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A lux is the illumination received on a surface
that is 1 meter from a standard light source
known as unity.
A lux is and international measurement
comparable in use to the metric system.
In the United States, the footcandle unit is more
commonly used and understood.
One footcandle is equal to the amount of light
produced by a standard candle at a distance of 1
foot.
A light meter is the only way to measure light
intensity accurately.
A light meter is the first piece of equipment that
should be bought by a plantscape designer.
 The keys to a plant’s survival are acclimatization
and maintenance of the minimum light intensity
required for its survival in an attractive and
healthy condition.
 Acclimatization is defined as the adjustment of
an outdoor plant to interior conditions.
 The minimum light intensity is the level of
illumination necessary to allow acclimatized
plant to produce new leaves at a rate equal to or
slightly greater than the rate at which old leaves
senesce and abscise.
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The term used to describe when leaves
age is senesce.
 The term used to describe the falling off
of leaves is abscise.
 Light intensity is reduced gradually over a
period of several weeks or months. The
acclimatization process cannot be rushed
without a severe reaction (defoliation, or
death).
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During nutrient acclimatization, high fertility
levels in the soil is unnecessary, and thorough
soil leaching at the beginning of the
acclimatization period and occasionally
afterwards will prevent a buildup of soluble salts.
 During moisture acclimatization, the frequency
of watering is reduced to prepare plants for their
more stressful interior locale.
 During temperature acclimatization,
temperatures are gradually reduced to the range
common to most interior areas (65 -75 F).
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Light quality is the color of light emitted
by a particular source.
 Plants depend upon blue and red bands of
the visible light spectrum.
 The unit of measurement for light
wavelengths is the nanometer.
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Five questions to consider when selecting the
proper lamp for illumination of an interior
planting:
– How extensive is the planting?
– Are the plants to be encouraged to grow or merely to
be maintained at their current size?
– Will the plants receive any sunlight? If so, how much
and for how long?
– How far will the artificial light source be from the
plants?
– What types of lamps are being used for general
lighting of the area and what is the intensity of
surface illumination provided?
Special effects such as shadows or textural
highlights can be created with incandescent lights
installed beneath the plants and directed upward.
These are called uplights.
 When supplemental lights are added for overhead
illumination, they should be positioned to light the
plants fully without shining in the eyes of viewers.
 The most important of all light sources for interior
plantscapes is natural sunlight when it can be
planned for and depended on.
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Sunlight entering from overhead is of greater
use in the illumination of interior plantings than
light entering from the side.
 The medium that serves when plants are
growing in a nursery field or production
container is likely to be inappropriate for an
interior installation.
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Problems with natural field soil include:
– Too heavy to permit rapid drainage
– Too heavy for the floor to support if the
container is large
– Inconsistent in composition, making
standardized maintenance of separate
planters difficult.
– Infested with insects, pathogens, or weeds
Indoors, photosynthesis is reduced to survivalmaintenance levels, so the root system need not
be as large.
 One of the first steps at the time of installation
is to remove production medium from around
the roots and prune away excess roots.
 More interior plant deaths result from overwatering than from any other reason.
 The need to water a planting can be determined
by feeling the soil and observing its color.
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When water is applied, it must be in a quantity
adequate to wet the soil deeply, not shallowly.
Deep watering promotes deep and healthy rooting
while providing the soil leaching necessary to
prevent soluble salt buildup.
Fertilization is needed to provide the mineral
elements required for photosynthesis.
Too much nitrogen may lead to spindly, succulent,
and unattractive growth.
Excessive fertilization follows only slightly behind
overwatering as a major reason why interior
plants fail to survive satisfactorily.
Humidity is seldom a problem for plants growing
outdoors, but can cause a problem for interior
plantscapes.
 If the correct precautions are not taken, plants
can experience ethylene poisoning during
shipping. This is caused by the exhaust and can
severely damage the plants. Proper ventilation is
the key to preventing this problem.
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Air pollution cannot be escaped by bringing the
landscape indoors.
 Proper ventilation will carry away chlorine
vapors, fumes from smokers and chemical
cleaning agents, or the ethylene which may be
present if a building is heated by some form of
hydrocarbon combustion (fossil fuel).
 Dust is an air pollutant different from the others
in that it is a particulate not a vapor.
 Air filtration reduces the amount of dust.
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Pruning will not be extensive in an interior
planting because of the plants’ reduced
rate of growth.
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Repotting of plants is necessary in
plantings where growth is allowed.
Five common pests in interior
landscape
Aphids
Mealybugs
Spider mites
Common Pests Continued
White Flies
Scale
The only real defense against vandalism to
interior plants is public education and
cooperation.
 Grouping compatible species is used often
in interior plantscapes. By using plants
which have the same requirements for
light, moisture, fertilization, and soil mix,
grouping helps simplify maintenance.
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The success of the plantscape is measured
by its appearance and health.
 No greater field in ornamental horticulture
holds greater promise than interior
landscaping.
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