How to Determine Light Requirements for Houseplants

How much light do house plants actually need? Light is measured in units called "foot candles," which refer to the amount of light emitted by one candle at a distance of one foot. Here is an easy way to understand your plants' requirements and determine the if the light conditions in a room are adequate.

Difficulty: Easy

Instructions

Things You'll Need:

• Plant Light
• White Notebook Papers

1. Understand that low-light plants require at least 25 foot candles of light. That is equivalent to the amount of light shining through a north-facing window.

2. Understand that medium light plants require 75-100 foot candles. This is equivalent to an east- or west-facing window.

3. Understand that plants with high light requirements need at least 200 foot candles. You can get this amount of light from a south-facing window.

4. Understand that very high-light plants need at least 2000 foot candles of light. To achieve that amount, you will need to grow your plants under fluorescent lights.

5. Place a piece of white paper near the location you wish to set your plant.

6. Put your hand about 12 inches from the paper between the light source and the paper. If you see a distinct shadow, the location has high light. If you see a shadow, but the edges are fuzzy, you have moderate light. If you barely see the shadow at all, the area has low light.

Tips & Warnings

• To be a successful indoor gardener, try to provide the type of light each plant requires. Usually, light specifications are indicated on the label.
• Most gardening manuals will indicate what type of light is required by each variety of plant.

[SunflowerOcity]

on 11/30/2007 Bravo!
I enjoyed your article and rated it with five stars! Please check out plant light article at the following link:
http://www.ehow.com/how_2143383_providing-plants-proper-light.html
Thanks!
Chris

on 8/8/2006
How to read light level with an SLR camera?

Using your SLR camera in manual mode, you can measure light level:


Set camera ASA speed to 200.

Set camera shutter speed to 1/125.

Hold a large, white card (or sheet of paper) in the proposed plant location so that it gets max illumination.

Be sure that nothing but the white card is showing in the viewfinder.

Adjust f-stop on camera (or lens) until camera meter reads "correct exposure"

f4 = 64 foot-candles
f5.6 = 125 foot-candles
f8 = 250 foot-candles
f11 = 500
f16 = 1000
f22 = 2000
f32 = 4000

on 11/22/2005
How to read light level with an SLR camera?

Using your SLR camera in manual mode, you can measure light level:


Set camera ASA speed to 200.

Set camera shutter speed to 1/125.

Hold a large, white card (or sheet of paper) in the proposed plant location so that it gets max illumination.

Be sure that nothing but the white card is showing in the viewfinder.

Adjust f-stop on camera (or lens) until camera meter reads "correct exposure"

f4 = 64 foot-candles
f5.6 = 125 foot-candles
f8 = 250 foot-candles
f11 = 500
f16 = 1000
f22 = 2000
f32 = 4000

on 11/22/2005 Make a point to open your curtains or blinds every morning so your plants can get enough light, it's so easy and makes a huge difference!