Effect Description:

Plants use a process called photosynthesis to make or synthesize carbohydrates using water, nutrients, carbon dioxide and sunlight, hence the term photo ”synthesis”. These carbohydrates fuel the plants activities including growth, repair and movement.

This means that light plays a vital role in a plants overall development and is essential to life for a plant. If you cut back the light a plant will suffer and you place it in the dark it will die. That’s why determining the optimal light levels for the plant you are growing is so important.

Providing light for a plant means more than just sticking it near a window and hoping for the best. It means providing the proper ‘duration’ of light and the appropriate ‘intensity’ of light. Plants need between 12 and 16 hours of natural light to maintain growth. The intensity on the other is dependent on the particular strain ranging from cacti which require bright full on sun and ferns which require semi-shade or they will suffer severe damage.

Most plants that are purchased include a stick-in information stick which contains information about watering, feeding, temperature and light conditions. Follow these recommendations and better yet, do some of your own research on the plant you are growing to learn even more about the requirements.

Symptoms and Damage:

Too little light

  • Yellowing leaves on the whole plant
  • Leaves are much smaller than they should be
  • Brown tips on leaves
  • Brown edges on leaves
  • Lower leaves dry up and fall off
  • Plants with variegated (patterned) leaves lose their patterns
  • Stems become elongated and spindly as the stretch for the light

Too much light

  • Brown, scorched patches on leaves, known as sun scorch
  • Leaves look lighter than normal, almost faded
  • Plant wilts or collapses
  • Dry leaves that fall regularly

First Aid for Light Issues

  • Low Light - As always research the plant you have to determine the best possible conditions and try to provide them.
  • Sunscorch - Remove the plant and mist it to keep it cool if scorch is noticed during the day. You can trim the affected areas and allow new growth to occur.

Additional Considerations:

  • Artificial light may be used in areas were not enough light is available to grow plants using common flourescent bulbs. Many kits are available to the home gardener or you can make your own.
  • A light meter can be used to accurately determine an areas light levels.
  • Some window glass can actually magnify the sun's rays, take care when placing plants near windows.
  • Research the plant you are growing as all plants have different light requirements.