Using T5 Grow Lights for Cannabis
T5 Grow Lights & Other Fluorescent Tubes
A few years ago, growers usually only used fluorescent tube lighting as a supplemental light for cannabis plants, or for young seedlings and clones only.
In recent years, we’ve seen the creation of new high-light-output versions of fluorescent grow lights which can actually be used through the entire vegetative stage.
Some growers even use fluroescent grow lights such as the T5 successfully to flower their plants (if the plants are kept short/small enough through growth control methods).
In general, I recommend changing to stronger grow lights like LEDs or HIDs for the flowering stage because they will usually give you double or more yields/watt of electricity. Unless you keep your plants very small, they will need more light to produce buds than a fluorescent light can usually produce. If you’re in a dire situation where your plants have grown too big and you can’t afford to get a different type of light, you can supplement your fluorescent tubes with additional light, for example you could supplement their light with a few CFL(compact fluorescent light) bulbs wherever you notice any “shadowy” areas. This is only a minor fix – the real fix is to grow very short plants or upgrade to a bigger light for the flowering stage.
Training plants to grow very short will produce the best yields with T5 grow lights
The biggest problem with fluorescent tubing is that the light that they give off is only useful for about a foot or so. That’s why they’re kept so close to your plants.
T5 grow lights should be kept as close as possible without burning your plants.
Any part of the plant that is further away then 1-2 feet from the fluorescent grow lights is not getting an optimum amount of light, especially in the flowering stage when plants need a lot of light to produce buds.
With the new high output lights such as the T5, fluorescent lights can be used until the plants are about 24 inches tall, which is just enough to grow a very short plant through to the flowering stage when you control your marijuana plant’s growth through the vegetative stage.
The great thing about fluorescent grow lights is that they don’t get very hot, and they can usually be kept 1-4 inches from the tops of the plants at all times without having to worry about burning your cannabis leaves or buds.
The other great thing about fluorescent lights is that they are usually relatively low powered and won’t make a huge mark on your electricity bill.
There are many different levels of fluorescent grow lights including the T5, the T8 and the T12. I strongly suggest sticking with the T5 style of fluorescent grow lights for cannabis because they give off the most amount of light for the size, and are specifically designed to be able to support taller plants up to 24 inches.
If the temperature is under control they can be kept as close as an inch or two away.
For optimal results, for vegetative growth choose fluorescent light bulbs that are labeled either as “Cool White” or “Cool” colored (also labeled as “6500k” colored).
For flowering, choose bulbs that are “Warm White” or “Soft White” colored (usually labeled as “2500K” or “3000K”).
Example of a ScrOG (Screen of Green) Grow Under a T5. Using a screen can be an effective way to create a flat, table-top shape to take the best advantage of T5 grow lights
However, you can use either type of lights during either stage and still get good results. People also use “Daylight” (5000K) bulbs with success.
If possible, opt for bulbs labeled as “High Output” (HO). This ensures that you’re getting the most lumens (light) from your bulbs. But any T5 bulbs will work – hundreds of cannabis growers have the harvests to prove it!
Fluorescent lights like the T5 can be used to grow a cannabis plant from seed to harvest, but it may not be a good choice for the flowering stage unless you train your plants. Learn more!
Here Are The 5 Best Fluorescent Lamps for Growing High-Quality Cannabis
There’s a lot to learn when you enter the world of marijuana growing. Newbies are confronted with a vast wealth of information and a steep learning curve. You need to learn about watering, feeding, pruning, and more. But before you even begin to grow your cannabis plants, you need a set-up.
Establishing the space where you will grow your plants is crucial. Many strains can thrive outdoors, but most cultivators opt for indoor set-ups where they can control the temperature and light thoroughly. Since marijuana strains can be picky and sometimes require different conditions at different growth stages, indoor growing can provide you with the highest yield – if you do it right.
There is much debate about what lighting type is the best for marijuana. Fluorescent lighting is a commonly used form of lighting, but you still need to learn which bulbs work best. In this guide, we cover the pros and cons of fluorescent lamps and explain where you can pick up the best fluorescent light for your grow space.
Why Use Fluorescent Grow Lights for Cannabis?
Fluorescent lights are ideal for newbie growers who are experimenting with cultivation. While they are pretty useless for big growing operations, fluorescent bulbs work well in a small grow space.
Fluorescent lighting works through a chemical reaction inside the bulb. Mercury vapor reacts with various gases to create an invisible UV light, which then illuminates phosphor powder that creates light. For this process to take place, you also need electricity; the current is what triggers the reaction. As a result, you often end up needing a socket for each bulb.
There are two types of fluorescent lights: CFLs and T5. A CFL bulb has a twisted, coil-like shape, whereas T5s come in straight tubes.
The type you choose is really up to you and the size of your grow room – T5s might work better in a slightly larger space. Either way, fluorescent bulbs are not as powerful as other lighting types. As a result, they are best for small grow rooms with only a few plants. Cultivating on a larger scale requires the use of HIDs or LEDs, for example.
Growers who have complex lighting set-ups using multiple lighting types often use fluorescent bulbs during the sprouting stage. Young plants respond well to these bulbs, but older plants sometimes require something more powerful. Sadly, you may get lower yields than if you used LEDs at a later stage.
Fluorescent Lamp Pros
- Cost-effective thanks to low electricity usage.
- Relatively cheap compared to other lighting types.
- Very widely available.
- Ideal for small grow spaces with a few plants.
- They work well for seedlings and young plants.
- Low heat output means they can be placed close to plants.
Fluorescent Lamp Cons
- Can’t be used in larger grow rooms.
- Lower yields because the lights are less powerful.
- Every bulb requires a socket.
- Shorter lifespan than other bulbs.
What are the benefits? …
Other Types of Lights
There are several types of lights that marijuana growers typically use. The most popular are LEDs and HIDs, which are both used for larger grow spaces.
LEDs (light-emitting diodes) are a favorite with growers because they last long, are super energy efficient, and emit very little heat. Still, they are powerful enough to produce high yields at the end.
HIDs (high-intensity discharge) are even more powerful, but they aren’t as energy-efficient and they use a lot of power. As such, they can give off quite a bit of heat. You may need to invest in a ventilation system to counteract this, leading to a higher cost.
As you can see, choosing the best fluorescent light is a bit of a trade-off. That’s why professional growers will change between different types of lights during different stages of growth. If you’re not that serious, though, and are just planning on growing one or two plants, then fluorescent bulbs will work just fine.
CFL vs. T5 Tube Fluorescent Bulbs
Compact Fluorescent Lamps (CFLs) have a coiled, twisted structure. These bulbs have a varying wattage, with some almost rivaling HIDs. Since CFLs are so common, you can find them at most household stores and even grocery stores. This is a blessing, but the downside is that you’ll need a separate socket for each CFL bulb.
Another great thing about CFLs is that they can be positioned in innovative ways. Some people place them horizontally, while others dangle them vertically over the plants. Since they can fit into a small space, they’re pretty good for stealth growing.
The downsides of CFLs is that they are less efficient than more powerful lights. Furthermore, you may need to keep moving and repositioning the bulbs for best results.
T5s, meanwhile, get their name from their tube shape and 5/8” diameter. T5 bulbs usually come in a set, where multiple tubes are placed side by side in a panel. As a result of this set-up, T5s provide more even light coverage. You’ll need to hang T5s from a fixture, but don’t worry, as they’re often very cool and won’t cause heat damage.
T5s are the preferred fluorescent bulb of choice for more experienced growers. However, CFLs definitely work, too. Bear in mind that you’ll have to put up with a smaller yield with both types of fluorescent lighting.
5 Best Fluorescent Lamps for Growers in 2021
Here are WayofLeaf’s top picks for fluorescent grow lamps. These should suit all budgets and grow spaces, no matter what you need.
1. Hydrofarm FLC125W Compact Warm Fluorescent Bulb
This warm fluorescent bulb is designed for flowering plants, potentially negating the problem that often occurs with CFLs during the flowering stage. Most growers use this bulb with a reflector to ensure the best distribution of light.
For a relatively cheap price, the Hydrofarm FLC125W light provides excellent light quality. It can be placed both horizontally and vertically. The bulb provides 125-watt full-spectrum light in a warm tone.
The brand offers a 1-year warranty on this product, and most customer reviews state that there have been no problems.
- Warm, full-spectrum lighting
- No heat given off the bulb
- 1-year warranty
- Ideal for flowering plants
2. Apollo Horticulture 250-Watt CFL Compact Fluorescent Grow Light Bulb System – 6400K
Even stronger is the Apollo Horticulture 25-Watt bulb. This CFL bulb comes with a USA standard reflector and a 13ft power cord, perfect for setting up your grow space. The bulb is 6400K, but the brand recommends switching to a 2700K lamp during the flowering period.
Growers recommend using this light in spaces that measure 3’x3’ or more. The reflector itself is 19” x 19” x 5”.
Apollo Horticulture describes this bulb’s light as “warm and inviting”. It makes a pleasant and effective addition to your grow room.
- 25-Watt, 6400K bulb
- Comes with a 19” x 19” x 5” reflector
- 13ft power cord means you can set it up anywhere
- Easy to set up for horizontal use
3. EnviroGro FLT24 2-ft T5 Bulbs
If you’re looking for T5 bulbs, then this option is fantastic. The EnviroGro FLT24 T5 lights are a little more expensive, but we think they’re worth it.
You can buy this product in multiple versions. First off, you can choose between 2ft or 4ft lights. Then, you can decide whether you want two, four, or eight tubes. The EnviroGro bulbs have a sturdy, reliable construction and come pre-assembled. All you need to do is plug it in.
You can hang the lights overhead, vertically, or horizontally closer to the plants according to your preference. There is a 10ft grounded power cord to help you reach, and the powder-coated steel housing protects the T5 tubes.
- 3” x 13.5” x 23”
- Powder-coated steel casing
- Multiple options for sizing
- Hangs both overhead and horizontally
- Features 6400K bulbs
4. Durolux T5 Grow Light (4ft) Dl844S Ho Fluorescent Hydroponic Fixture
The Durolux T5 grow lights have a super high light output of 20,000 lumen. The four tubes come in a German Hammertone Reflector, which provides 30% more light output. Each bulb is 6500K and measures 4ft. There are hanging hooks featured to help you position the lamp overhead.
Although this model doesn’t offer vertical positioning like the EnviroGro FLT24, it does offer two modes of light. Switching off some of the tubes allows for dimmer light that works better for times when you need it a little darker.
With an 8ft power cord, this model also has the advantage of being water safe. The Durolux model should remain safe in damp conditions. Plus, there is an AAG Stucchi lampholder that prevents fire if the tubes become loose.
- Light output of 20000 lumen
- 95% reflective sheet built-in for better distribution
- Outlet featured on the fixture; power up to 5 fixtures from one wall outlet
- Features modes for dimming
- Fire and water safe
- 8ft power cord
5. Hydrofarm FLCDG125D Fluorowing Compact Fluorescent System
Hydrofarm is back again with the Fluorowing Compact Fluorescent System. This model is designed for a small grow space of 2’ x 2’, with 125-watt bulbs. You will need to add additional reflective sheets for maximum efficacy, but this light is still decent for small spaces.
The FLCDG125D is CSA-certified and comes with a small reflector already attached.
Please note that this bulb is not the best on the market. However, it is cheap and will do the job in the smallest grow tents.
- Full daylight spectrum of light
- 125-watt bulb
- Lightweight and compact
- Can be positioned in various places around the room
- Reflector attached for better light distribution
Final Thoughts on Fluorescent Lighting for Cannabis
So, there you have it. These are our five top picks for fluorescent lighting that will show some love to your cannabis plants. Make sure to do your research, though, as there are hundreds of fluorescent lamps available on the market.
While fluorescent lighting may work for small-time growers with a handful of plants, you will need to invest in an upgrade if you’re wanting to produce more marijuana. LEDs and HIDs are much better for getting a higher yield.
And, before you start growing, make sure you check the current laws in your state. Many localities limit the number of plants you can grow at one time, so check to see what your allowances are.
Fluorescent lamps are a popular option for growing cannabis. Here are the pros and cons along with some of the best models on the market.