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Let's take a look at CFL lights for growing weed. There are quite a few options for lighting when looking to grow cannabis indoors. CFL lightbulbs are becoming more popular because they are beginner-friendly and easy to use. The best CFL lights for growing weed will help you produce more marijuana in small spaces than you thought was possible. If you have a small space that you want to utilize for growing ganja, CFL lights may be the best option!

What Are CFL Lights?

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.

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.

CFL Lights For Growing Weed

CFL Light Bulbs For Growing Weed

 Using CFL bulbs for plants and producing marijuana on your own doesn’t have to be complicated. CFL lights are the most beginner-friendly setup. They are also the best choice for small spaces. Beginners shouldn’t grow too much for their first experience, meaning CFL lighting is a win-win for cannabis growing for beginners.

Using CFL bulbs allows you to use daylight mimicking CFL bulbs during the vegetative stage of the plant’s life and use a softer light for the flowering cycle. You don’t want to use a soft white CFL for vegging as it is closer to the sunlight in Autumn when plants start to flower. However, if soft white is all you can find, it will still work as long as you have enough wattage to supply ample light to each plant.

 How To Grow 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.

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

While the wattage of the light produced by the CFL bulbs is more important than the spectrum of light, optimizing the spectrum is a good idea.

The best CFL for vegetative growth will be somewhere around 6500K. A softer spectrum around 2700K will be a good choice for a CFL flowering bulb. These spectrums mimic natural daylight spectrums in Spring/Summer during the growing cycle and Autumn for the flowering cycle.

 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.

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 Grow Light Coverage

As mentioned, the coverage of one CFL bulb will only produce enough light exposure to about 12 inches away from the bulb itself. This means that you’ll probably need multiple lights per plant to account for lateral growth.

Since CFL lights are only optimal up to about 12 inches below the light, it’s best to train your plants to grow horizontally instead of vertically. Topping your plants and tying them to grow more laterally is the best way to ensure your plant can grow large without being too tall for CFL full spectrum grow bulbs.

 The CFL light spectrum isn’t as important as the total wattage of the light produced when growing cannabis, but it doesn’t hurt to use daylight simulating CFL bulbs during the growing stage and soft-white CFL bulbs during the flowering stage.

If you are trying to do a single CFL grow operation with only one bulb, you need a small plant that flowers quickly, like an autoflower variety. Keep in mind that the yield of cannabis will be low with this setup. But, if you can’t spare more room than this, it’s still doable multiple times a year!

Pros & Cons Of CFL Lights For Growing Weed 


  • CFL offers the best fluorescent lights for weed for beginners and those on a budget
  • CFL grow room design is simple
  • CFL grow lights for flowering can be soft-white to mimic natural sunlight during Autumn
  • CFL setups are great for small spaces
  • Little heat is generated, compared to higher-powered grow light options
  • Your utility bill won’t be large


  • CFL lamps for growing weed aren’t as effective as more expensive lighting solutions
  • Not a great choice for tall-growing cannabis strains
  • Not a great choice for growing operations of more than 3-4 plants

How To Get Big Buds With CFL

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.

The sun produces about 100,000 lumens per square foot, so the closer you can get to this number, the more productive your marijuana plants will be. Building a hood for your CFL lights and concentrating them as close as possible during flowering will help mimic natural sunlight as much as possible.

Many novice cannabis growers do great with CFL setups during the vegetative stage but fail when the plants go to flower. If you want bigger, denser, more potent buds, you need maximal light intensity.

How Many CFL Lights For One Plant?

When setting up something like a small CFL closet grow, you might want as little light as possible. Each cannabis plant will require around 80 watts of light, with more being better. Using 2 40 watt CFL bulbs is sufficient for a mini CFL grow.

CFL Lights For Growing Weed FAQ's

Are CFL lights effective for growing cannabis?

CFL lights can help small-scale cannabis growers, especially those with limited space. Their decreased light intensity and heat output make them ideal for seedlings and young plants. They are less efficient for commercial or large-scale grows.

What are the benefits of using CFL lights for cannabis cultivation?

CFL lights are cheaper, energy-efficient, and emit less heat than HID lights. Their decreased heat output decreases plant heat stress and makes them perfect for stealth grows or confined places.

What spectrum of CFL light is best for cannabis growth?

Cannabis plants thrive under colder, blue lighting (6500K) during vegetative growth. For flowering, a warmer, red spectrum (2700K) is better. Growers may utilize multiple spectrums as the plant goes from vegetative to blooming.

How far should CFL lights be placed from cannabis plants?

Due of their lower intensity, CFL lights should be set 2-4 inches away from plants. However, the lights must not be too close to heat the plants.

Can I use regular CFL bulbs from a hardware store for growing cannabis?

Cannabis may be grown with normal CFL lights. However, bulbs should be the right wattage and color temperature (6500K for vegetative, 2700K for blooming). High-wattage bulbs work well.

How many CFL lights do I need for my grow space?

How many CFL lights you need depends on your grow space and plants. Generally, grow spaces should have 100 watts of CFL illumination per square foot.

How do CFL lights compare to LED or HID lights for growing cannabis?

CFLs are weaker and less efficient than LEDs and HIDs. They work well for small grows and are cost-effective, but not for larger operations or maximizing production and potency. HIDs and LEDs have a wider spectrum and higher light intensity.

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Do I need to change CFL bulbs during the cannabis plant’s lifecycle?

For vegetative and blooming development, utilize bulbs with various color temperatures (6500K and 2700K). Change bulbs or use a combination as the plant grows.

How often should CFL bulbs be replaced for optimal cannabis growth?

Even though they work like ordinary bulbs, CFL bulbs should be replaced every 6-12 months due to light intensity loss.

Is it necessary to have a cooling system when using CFL lights?

While CFL lights emit less heat than HID lights, appropriate ventilation is still vital, especially in enclosed spaces. Unlike HID lights, it requires a simpler cooling system.

Ready To Start Your CFL Cannabis Grow?

Growing pot with CFL light bulbs is doable for complete beginners with access to a small growing space. While there are better options for larger cannabis growing rooms, CFLs may be the best choice for those who only want to grow a couple of ounces for themselves. What do you think? Have you used CFL bulbs to grow marijuana?

Luis Cordova
Luis Cordova

Luis Cordova is a distinguished author, and renowned expert in cannabis cultivation, who possesses a Master's degree in Plant Biotechnology and Pharmaceutical Science. As a valued contributor to highly esteemed publications such as Cannabis Training University and Maximum Yield Magazine, Luis has emerged as a trusted source of guidance and knowledge in the cannabis industry. Having written thousands of informative articles, Luis is widely recognized for his comprehensive expertise on cultivating cannabis, both indoors and outdoors.

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