How many watts of led grow light you need for your plants?


Are you new to the led grow lights? If so, this article will help you choose the correct wattages for your grow space.


Before the led grow lights appear to the market, HID grow light is the main choice for people growing a large number of plants. At that time, wattage is an important parameter

for measuring the intensity of the light. The higher the wattage, the more intensitive the light are. We can even said that the wattage is the "relic" of HID grow light.


Actually, for led grow lights, wattage should not be used to determine the coverage area and how useful the light are. More efficient LED grow lights will use fewer watts to emit the same amount of light that a less efficient LED grow light will exude. It can only be used as a simple data for approximating the correct fixture size you need.


The actual watts of led grow light you need depend on:

1. Plant species

2. Growth phase

3. Grow area


Here has a quick guide about the wattage selection

All the wattages listed below are based on the flowering stage, maybe you can reduce your wattage by 50% during the vegging stage. And the data listed below for reference purpose only , as always, it is best practice to follow the manufacturer's recommendations.

Quick Guide


1'x1' : 32 watts (30-40 watts)


2'x2' : 128 watts (120-140 watts)


2'x4' : 256 watts (240-300watts)


3'x3' : 288 watts (250-300 watts)


4'x4':512 watts (500-650 watts)


5'x5':800 watts (700-900 watts)


4'x8':1024 watts (900-1100 watts)


6'x6':1152 watts (1000-1200 watts)



Recommended wattage assuming 1.0 sq ft/plant

numeber of plant           square feet             wattage
      1                        1                   30-40watts
      2                        2                   60-80watts
      4                        4                   120-140watts
      6                        6                   180-200watts
      8                        8                   240-300watts
      10                       10                  300-340watts


Recommended wattage assuming 2.0 sq ft/plant

numeber of plant           square feet             wattage
      1                         2                  60-80watts
      2                         4                  120-140watts
      4                         8                  240-300watts
      6                         12                 360-400watts
      8                         16                 500-650watts
      10                        20                 600-800watts 

Recommended wattage assuming 4.0 sq ft/plant

numeber of plant             square feet               wattage     
      1                          4                     120-140watts
      2                          8                     240-300watts
      4                          16                    500-650watts
      6                          24                    700-860watts
      8                          32                    900-1100watts
      10                         40                    1100-1400watts

(Above data reference:



If there are any concern or questions, please comment below, thank you for reading.

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