I got a light meter, and am surprised at the readings

[naoki]

Originally Posted by Magnus A

You are probably mixing up light values!

The very high values recommended is often the maximum light intensity at mid day at the natural habitat, close to the equator and that has very little to do with the plants need !

You have to consider the accumulated light energy the plants get over the day and if you use artificial light you have a constant flux of light over the day that is NEVER present in nature!


If those very high light values were correct it would be impossibly to grow orchids indoors in terrariums! And it is not!

I agree, some people are not interpreting the recommended intensity appropriately. This may be an interesting read. http://www.aos.org/Default.aspx?id=516 The title of this article seems irrelevant, but it clarifies the difference between the sun and continuous source

[My Green Pets]

That was...some science right there. So I should be looking at 50 to 70 percent roughly of the maximum recommended levels? Either way, my experience this winter has shown me that at less than 2000 lux and a photoperiod of less than 8 hours, my phals will spike and flower, although the flower count is low.

[bil]

Originally Posted by CambriaWhat

Lol. I am going to take a chill pill and let mother nature do her thang. Right now they're dealing with an 8-hour photoperiod and the sun at a very low angle. In six months, the days will be 16 hours long and sunlight will be pouring in those windows. Can't wait to take some light meter readings then!

Your plants are lush and dark green. I was told that's a sign that they aren't really getting enough light.

[Optimist]

Plants and humans use light differently. Plants photosynthasis has do with color wavelengths, not light intensity. Foot candle light meters are for photography.

Plants photosynthasise using the orange and red spectrum, at about 600 to 700 kelvin.


The human eye can only see about 550.

I kind of think when people say Light, they are all talking about different things.