Growing under lights

(Question)

I bought an Agro light for my indoor plants since there is not enough sun coming thru the windows at this time of the year. Can you please tell me as to: 1. How many hours should I turn it on? 2. What is the correct distance from the light source to the plants? 3. What are the do’s and dont’s? Unfortunately, there is no information in its package. Thanks.

(Answer)

If you are growing flowering indoor plants you will need 14-16 hours of light per day. Foliage plants will require only 10-12 hours, but seedlings require 16 hours of light. It is however important that you don’t leave the lights on all the time as plants need some darkness in order to grow properly. The easiest way to make sure this happens is to attach a timer to your lights.

Most indoor plants should be between 6-12 inches from the light source. Seedlings however should be positioned much closer at 2-4 inches away. As plants grow you can adjust the height of the chains. Keep in mind that the intensity of light drops rapidly as the distance from the tubes increases. You should also be aware that the center of the tube is the brightest spot and that the ends produce less light.

If plants are not getting enough light, they will get tall, spindly and pale. The lower leaves might even turn yellow and fall off. If however plants get too much light the leaves may bleach, brown or shrivel.

It is generally recommended that you use one “cool white” fluorescent tube and one “grow light” tube in your fixture when no additional natural light is available. In your case however since you still have some natural light, you can use two of the less expensive cool white tubes. You will get enough light that is in the red end of the light spectrum from your window and the cool white fluorescent tubes will provide the orange, yellow- green and blue end of the spectrum. I hope this helps you have a successful indoor growing season.