Aspects of Light:

1. Intensity - brightness or level of light

2. Duration - day length or photoperiod

3. Quality - color of light

 

Light Intensity:

Light intensity, the brightness or light level, is accurately measured with a light meter. The units of measurement are either foot-candles (British system) or lux (metric system). Light intensity is the limiting factor in growing plants indoors. Plants with variegated or colored leaves generally need more light because photosynthesis does not occur in these leaf surface areas.Artificial light sources such as Gro-Lux or Vita-Lite may provide the necessary additional light for these plants.

 

Light Duration:

Light duration, the length of daylight or photoperiod, affects the flowering capability of certain plants. There are three types of plants according to their flowering response to day length: Short Day, Long Day and Indeterminate.

 

Short Day Plants:

These indoor plants require less than twelve hours of light per day in order to initiate flower buds. If inadvertently given more light the flower buds will not develop. They all flower in the winter months around Christmas time. Christmas Cactus, Chrysanthemum, Kalanchoe, Poinsettia.

 

Light Quality:

Light quality refers to the color of light. White light, which is actually a combination of all of the colors, is best for plants. Red light is important for photosynthesis and photoperiodism. Plants absorb red light and reflect green light which is why most plants have a green leaf color. Orientation Toward Sunlight: Orientation toward south or west sunlight either inside or outdoors provides high light or full sunlight conditions. Conversely, plants situated in east or north windows or on the east or north side of a house receive lower levels of sunlight. The angle of sunlight during different seasons of the year is also a consideration for the light requirement of plants.

 

High Light Houseplants:

These house plants require high light levels. They prefer the bright direct sunlight of south or west windows. Examples: Aloe, Agave, etc (succulents). Cerus, Euphorbia, etc. (cacti) Citrus. (calamondin orange) Codieum. (croton) Crassula (jade plant) Hibiscus (rose of China) Hoya (wax plant) Kalanchoe (flaming Katy) Nerium (oleander) Yucca (spineless yucca)

 

Low Light Houseplants:

Certain house plants, usually ones with larger leaves to trap more light, tolerate lower light levels than others. They may be situated in a north or east window and include: Aglaonema (Chinese evergreen), Aspidistra (cast iron plant), Homalomena (emerald gem), Monstera (split-leaf philodendron), Philodendron (heart- leaf, selloum or Xanadu), Sansevieria (snake plant), Spathiphyllum (peace lily).

 

Houseplants for Children:

These indoor house plants offer unique or interesting features or characteristics to children. Chlorophytum (spider plant-has hanging plantlets) Kalanchoe tomentosa (panda plant - has fuzzy leaves) Lithops lesliei (living stones - look like rocks) Maranta leuconeura (prayer plant - leaves fold at night) Mimosa pudica (sensitive plant-leaves fold when touched) etc.