Retail: $36.95
Price: $31.95
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What do these numbers mean?

Green Thumb Grow lights are great for helping orchids, dwarf citrus, bonsai and all houseplants to maintain healthy growth. This grow light comes with your choice of a full spectrum 40 watt CFL bulb or 23 watt LED bulb. The 2700k bulb provides increased output in the red spectrum which promotes flowering in plants. The 5000K bulb is full spectrum bulb which promotes overall plant growth. Both bulbs have a 2600 lumen output (Equals to 200W incandescent bulb). Bulbs fit into a standard medium socket. Requires 110/120 volt outlet.

Green Thumb Grow Light Includes

  • Black clamp-on fixture with 6' power cord
  • Choice of 40 watt CFL or 23 watt LED grow light bulb


  • Primary growing area: 1' x 1'
  • Secondary growing area: 2' x 2'
  • Recommended height above plants: 3" to 1.5'
  • Light output: 2600 lumens
  • Heat output: Very Low
  • Bulb life: (CFL) 10,000 hours, (LED) 25,000 hours


Growing Area
The growing areas listed above assume the light bulbs are being used in a fixture
with a reflector similar in quality to the ones offered on this web site.
Primary - Use this area if the grow light will be the main or only source of light for the plants. This includes areas where minimal light comes from windows or standard house/office lights.

Secondary - Use this area if the grow light will be used in a greenhouse or other area that receives direct sunlight for part of the day to supplement the light from the sun.
Heat Output
Type of Bulb
Average Bulb Temperature
LED & T5 Fluorescent
100 to 120° F
CFL (Compact Fluorescent)
130 to 180° F
220 to 260° F
MH and HPS
450 to 550° F
How Long Should Grow Lights Run?
This depends on the type of plant. Foliage plants need about 14-16 hours of light per day. Flowering plants need 12-16 hours of light per day. You should give most plants at least 8 hours of total darkness daily. Try to have the lights on at the same time every day. Using an automatic timer for your lights is recommended to make it easier.
The Electrical Cost to Run a Grow Light System
To get the operating cost per hour for a light, take the lights combined wattage, and divide it by 1000 to get the kilowatts used. Then multiply that number by the amount your electric company charges per kilowatt hour. HID lights will use the number of watts it emits per hour, ie; 600w system will use 600 watts per hour (regardless of spectrum).
(light wattage output / 1000) x electricity cost per kilowatt hour = Operating cost per hour
operating cost per hour x hours used per month = Operating cost per month

Item # 5605160, 5605165, 5605170, 5605175

Overall Customer Rating of 5 Reviews:

Perfect for my calamondin tree!

I bought two of these for my calamondin tree. The tree is thriving even though it is growing indoor. It does get about two hours of sunlight through the glass door in the afternoon but it needs more than two hours of light in order to become healthy. When I first got my tree (ordered online), it is not as lush as it is now. As expected, for the first two weeks, it lost some of the young leaves due to the stress it went through during shipping. Now, it has grown more new leaves and it has more flowers and tiny fruits. I bought the grow lamp that is LED. It does get a little warm but it is not hot enough to burn if your hand or the leaves accidentally touch the light or the reflector.

Washington state

Grow light for my citrus plants

Seems to be working well, both trees are healthy. Great customer service!!

New York

Very Nice Grow Light

I'm very happy with the grow light itself. Now I just need someone to come over and remind me to use it every day!


It does the job I bought it for

This light are bright enough for my indoor plants. I think it is going to be exactly what I want.

Boise, Idaho

Strong Clamp and Bright Bulb!

Very good for the price. I was especially impressed with the clamp -- it is very strong and it is made out of rubber so it is less likely to scratch or damage whatever object you might clamp it to.
My dad commented that this clamp light fixture is also a very convenient way to move a light around -- and I would say he is right. This fixture seems to be a great choice for a portable light source. (Certainly easier than trying to move an entire lamp around).
The bulb is brighter than I expected. After only a few days, you can see the plants perking up and starting to grow towards the light.