growing weed under cfl lights

Growing weed under cfl lights

More Light = Better Results with CFLs. In fact you pretty much can’t really give your plant too much light when growing with CFLs (this isn’t true for all grow lights).

This will help you estimate how much yields to expect from your CFL grow, but you need to remember to take this with a grain of salt. A very general rule of thumb is to expect about 0.25g/watt of CFL light if you use plant training and don’t run into major plant problems. This is counting CFL true watts, not any type of “equivalent” watts. Some CFL growers definitely get bigger yields than that with CFLs, up to about 0.5g/watt for the pros, but 0.25g/watt is what you should expect as an upper limit for a first-time cannabis grower.

There are bulbs with different CFL color spectrums and it’s generally recommended to get “daylight” (6500k) CFLs for the cannabis vegetative and “soft white” (2700k) CFLs for the flowering stage. Each color spectrum has a small impact on how the plant grows (ex: 6500k encourages slightly more squat growth).

What Color CFLs Should I Get? (CFLs and Light Spectrum)

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Growing weed under cfl lights

To get big, productive buds when using fluorescent light bulbs for growing weed, you need the most light intensity that you can produce. This is the most important factor when flowering with CFL lights.

You can grow marijuana with CFL grow light bulbs in soil or hydroponically. Regardless of the growing medium, light needs remain the same.


They come in a variety of different bases, so flexibility when designing a grow operation won’t be a problem. CFL lights don’t use excessive energy and don’t heat up as high as some other specialized grow lights for marijuana.

How To Get Big Buds With CFL

Growing cannabis with CFL lights is simple to set up and maintain. Each plant will require around 80 watts of light, although more can be better. Since CFL light bulbs for plant growth don’t produce enough light exposure beyond around 12 inches, the lights will have to be adjustable with height to account for plant growth.

Investing in a timer to turn the CFL lights on and off on an optimal schedule for the plant’s stages of life is a good idea. It’s also a good idea to invest in high-quality growing medium and nutrients to improve yields.


CFL Light Bulbs For Growing Weed

CFL is an acronym for compact fluorescent lighting. Compact fluorescent grow light setups are easy to build out because you can buy CFL grow bulbs at almost any store that sells light bulbs! They are just like fluorescent light bars seen in stores and offices but packed into a small lightbulb, allowing the user to reap the benefits of fluorescent light without a large lamp setup.

However, this doesn’t make or break your cannabis growing operation. If you don’t use a warm white CFL for flowering, you won’t ruin your marijuana. This advice is more about how to set up CFL grow lights in a perfect world.

Growing weed under cfl lights

A Note about Using CFL Lights

That’s because growing weed with CFLs isn’t the highest yielding method. It doesn’t get the most yields for the electricity, it’s not suitable for a large grow, and it’s not going to work if you aren’t willing to watch over your plants closely throughout the grow.

CFLs lose a lot of light the further away they are and their light is almost useless once the plant is 6-8 inches away.

These common bulbs are much more efficient than old-fashioned light bulbs (which can’t be used to grow plants) and CFLs don’t use much electricity or produce as much heat compared to some other grow lights.

Note: Perlite can often be found in garden stores or the garden section of places like Home Depot and Lowes. I normally advise against all things Miracle-Gro, but their 8-quart bag of perlite is okay for this tutorial if you can’t find anything else. But remember, never use Miracle-Gro time release soil or their standard nutrient formula! But their perlite is okay.