This may be a useful reference.
[url]http://palm_doctor.homestead.com/palm14.html[/url]
Foot Candles Chart for Palms
Moderators: lucky1, Alchris, Kansas, Wes North Van, Laaz
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Wes North Van
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Barb
That is what I deal with all day is footcandles.
600 footcandles is brighter than you will ever get your home so those are outdoor palms for sure.
600 footcandles is brighter than you will ever get your home so those are outdoor palms for sure.
Wes North Vancouver Zone 8b/9a
Keats Island BC Zone 8a
Palm Springs CA Zone 9b/10a
Keats Island BC Zone 8a
Palm Springs CA Zone 9b/10a
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lucky1
- Arctic Palm Plantation
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This relates foot candles to what we're used to, i.e. in the family room:
Visible light can be easily measured with a light meter (G. E. use to make a popular, inexpensive one that still can be found at used camera shops). Note that a light meter measures light at one time, that is instantaneously. It's not over a period of time. Footcandle is an instantaneous measurement of light. If you start to think about how bright certain levels of footcandles are, then you will start to understand the environment and light levels that indoor palms require. In the evening, inside your family room, with a TV on and a table lamp you might have 25 footcandles. The light in an office where it is to easy to read a book is usually about 125 footcandles. Sun light entering a south window often has levels of 500 - 800 footcandles. A typical shadehouse where indoor palms are grown has about 2000 footcandles. Outside, on a bright sunny summer day when the sun is directly overhead is around 10,000 footcandles. As you can see, you will almost never have as much light inside your house as in the nursery where the palms were grown, even if they came from a shadehouse with 80% shade.
I was wondering WHY the chart had TWO categories for palms requiring 300 foot candles.
Anybody know?
Allen, good. Me too. Good to know that full summer sun is about 10,000 !
Wes, so only the 600 group are the really critical ones for max light, especially in winter?
I'm asking because my Spindle is in the 400 group.
Barb
Visible light can be easily measured with a light meter (G. E. use to make a popular, inexpensive one that still can be found at used camera shops). Note that a light meter measures light at one time, that is instantaneously. It's not over a period of time. Footcandle is an instantaneous measurement of light. If you start to think about how bright certain levels of footcandles are, then you will start to understand the environment and light levels that indoor palms require. In the evening, inside your family room, with a TV on and a table lamp you might have 25 footcandles. The light in an office where it is to easy to read a book is usually about 125 footcandles. Sun light entering a south window often has levels of 500 - 800 footcandles. A typical shadehouse where indoor palms are grown has about 2000 footcandles. Outside, on a bright sunny summer day when the sun is directly overhead is around 10,000 footcandles. As you can see, you will almost never have as much light inside your house as in the nursery where the palms were grown, even if they came from a shadehouse with 80% shade.
I was wondering WHY the chart had TWO categories for palms requiring 300 foot candles.
Anybody know?
Allen, good. Me too. Good to know that full summer sun is about 10,000 !
Wes, so only the 600 group are the really critical ones for max light, especially in winter?
I'm asking because my Spindle is in the 400 group.
Barb
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Cali-wanna-b
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Thanks for the very usefull information!