Light and reflective floors
By Ed Rosenthal - Thursday, February 6 2003
I am setting up a room 6' x 4' with two HPS 600-watt lights. While setting up, I thought the use of a reflective "space blanket" on the floor would improve light penetration and plant growth. However, now having the lights and everything set up, I'm starting to think that this may be a bit of overkill and may actually damage the plants. I was wondering what your opinion would be on this subject.Also, are two 600-watt lights too much for this space?
AJW,
Adelaide, Australia
The room has a total of 24 square feet. Dividing the 1200 watts by 24, the total is exactly 50 watts per square foot. This is on the low end of the range of 50-65 watts per square foot I recommend for flowering.
Putting a space blanket on the floor to improve light reflectivity is a good idea in a small garden, where it won't be walked on. You could also use white polyethylene, which is sometimes available at indoor garden shops. It is usually offered in the 6-millimeter thickness, which is heavy enough to withstand rough treatment.
If you are planning to walk on the garden floor, you can increase its reflectivity by painting it white, or by making Styrofoam or white cardboard panels that can be pulled off the floor when you are working in the area.
Light does not damage the plants. More often, it is the heat that the lights produce which causes problems. The garden should be kept between 70-80?F (21-27?C). Fans, air conditioners, or vented air-cooled lights all help to keep the temperature within range.
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