Fall is the Time To Bring In Your
Begonias After Spending The Summer Outdoors.
How To keep Them Growing
Indoors Under Artificial Lighting
1. Metal Halide lights are blue-orientated in the spectrum. It is the best type of light to be used as a primary
light source (if no or little natural sunlight is available). This type of lamp promotes plant growth.
2. High Pressure Sodium lights are red/orange in the spectrum. They are the best lamps available for secondary
or supplementary lighting (used in conjunction with natural sunlight). This" type of light promotes flowering/budding in plants.
These are most commonly used by commercial growers but they consume a lot of electricity.
3. Sodium Conversion lamps allow you to tailor
the light source to the growth stage of the plant
(again using halide blue light for growth and
sodium red light for flowering/budding) merely
by changing lamps. These are also used mainly
by commercial growers and are an expensive choice
4. Fluorescent lights are economical and good for starts and seedlings but is a poor light source
for growth and budding primarily because of low lumen output. However, the amount of sunlight that shines in a greenhouse
is sufficient to grow spring bedding plants. Best success for growing seedlings in low natural light situations is achieved
by keep the fluorescent tubes within inches of the growing plants and raising the lights as they grow. Lights are typically
kept on for 16 hours each day.
5. Incandescent lights do not
require a ballast. Special “grow” lights typically come in 75 watt and 150 watt. They are good for starts and
seedlings or for individual or small groups of plants. These provide an inexpensive alternative to Halide and Sodium lamps.
The common T-12 fluorescent
light bulbs are being phased out and being replaced with a smaller T-8 bulb. The T-8s contain less mercury than the T-12s
and are more energy efficient.
*Information from
Central Penn Chapter
Hobby Greenhouse Association Newsletter
