Yes.

frostwoman,

Obviously, low-light plants such as African Violets would suffer under too much light.

If you are talking about sun-loving plants, then the answer is a maybe. They can get too much a day, that is, if they do not have a chance to "go to sleep in the dark." But that can take a month or more of 24/7 lighting o show up. Presumably, if someone wanted to hot the plants with lights double the intensity of the sun, and they got rid of the heat so it was not a factor, the plants would suffer.

I do know that lots of studies have been done when it comes to artificial lighting and plant growth. None tried to deliver too much light, except for denying a period of darkness and what was found was that there is a point where more light or longer periods does not equal better production.

The bottom line is that lighting is just one part of the equation, and what makes up the lighting is a sub-species.

Clear as mud, huh!

Mike

Hi,

I realize this is a case study and not empirical but... I live in the country, we grow a lot of corn and soybeans --miles and miles of corn and soybeans -- it's 20 miles to the nearest traffic light! Some years back the state built a prison in the middle of the corn and soybeans. The lights from the prison caused problems with the crops. Everything is so precisely controlled when it comes to crops it made it very easy to determine the problem was the lights. I don't remember how they resolved the issue, or if they resolved it -- fortunately they weren't my crops :) We (meaning humans) have such an impact on our environment.

Take care,
Luv_to_gardn

BTW -- I've been snowed in the past two days so I've been reading the posts off and on and commenting. I usually don't have this much time on my hands :)