T5 Grow Lights Buyers Guide
T5 grow lights are often used for the propagation and vegetative stages of plant development. They consume little power compared to other lighting methods and put out only a tiny amount of heat, which, with their compact design, makes them the favourite propagation and vegetative lighting solution for many growers.
What is a T5 grow light?
Like CFLs, T5 grow lights are a type of fluorescent lighting. The ‘T’ describes the shape of the lamp, standing for ‘tubular.’ The ‘5’ gives an indication of the diameter, which is measured in increments of 1/8 of an inch. For example, T5 lights are 5/8 of an inch in diameter and T8 lights are one inch in diameter.
Types of T5 lighting
In the horticultural industry, single T5 lights are often arranged side by side in a parallel array, usually in a reflective panel like the ones pictured above. This design offers the greatest spread of light possible.
The lights we stock are available in four different sizes:
- Two foot long two light panel
- Two foot long four light panel
- Four foot long four light panel
- Four foot long eight light panel
Both of the two foot long systems are supplied with 24W bulbs and both four foot systems are supplied with 54W bulbs. The full amount of light available differs with each system and the output is calculated by multiplying the wattage of each lamp by the total number of lamps.
For example, a two foot two light panel will output a total of 48W whereas a four foot eight light panel will output 432W.
All of the T5s we stock are supplied with blue spectrum bulbs. This is because T5s are primarily used for the propagation and vegetative stages of development when blue light is needed to promote healthy growth.
Red spectrum bulbs (usually used during the flowering / fruiting stage of development) are also available to accommodate growers who choose to use these lights through all stages of plant development. However, we do not recommend T5s as a standalone light for the flowering / fruiting stage, as you will notice considerably lower yields when compared with using a HPS grow lamp.
T5s are widely used in commercial settings for propagation due to the fact they carry several advantages over other types of lighting. For one, they are only 6cm deep which means they can fit neatly into most spaces, and they are perfect for growers looking to fully utilise their growing space by housing multiple propagation shelves vertically.
Secondly, the fact most systems use a number of T5 grow lights in a parallel array offers a substantially even spread of light, ensuring that all plants, including those located at the edge of your grow room, receive plenty of light.
Finally, T5 lighting systems come in a variety of sizes, use very little power, and output minimal heat, meaning they are suitable for use in any sized grow room and can be safely hung just a few centimetres above your plants without causing any issues. Low power consumption also means they’ll save you money on electricity costs over CFLs (small difference in cost) and HIDs (big difference in cost).
T5s can be used as a complete light source for the vegetative stage of plant growth. Growers have reported that using T5 panels in this stage can obtain similar levels of vegetative growth as using a metal halide lamp. The combined wattage output of a four foot panel will put out plenty of blue spectrum light to encourage healthy growth.
Flowering & fruiting
Both blue spectrum and red spectrum T5 bulbs exist on the market. Even though it is possible to use red spectrum T5s as a main light source for the flowering / fruiting stage of plant development, they are rarely used by growers because they simply cannot offer the same levels of performance and overall yields of a HPS lamp. If you want to get the most out of your plants, use a HPS as your main light source during this stage of development.
As a supplementary light source, red spectrum bulbs can give your plants an extra boost during flowering / fruiting. Additionally hanging T5 grow lights in your grow room whilst using a HPS lamp will produce little in the way of added heat and can provide extra light to those hard to reach areas where your HPS won’t have full effect.
To sum up
Although they don’t perform very well as a main source of light for flowering and fruiting, T5 grow light systems are great when it comes to propagation and vegetative growth. They often get results that are comparable to metal halide bulbs without carrying the added heat and electricity costs.
If you have not yet tried fluorescent lighting for these stages of growth then we highly recommend using a T5 system, or a combination of CFLs and T5 systems. You may just be pleasantly surprised by their high performance and reduced running costs.