Before we start learning, let us introduce ourselves. We are a craft growing club where our main mission is to provide free support to those who join. TheBudLab
is a team of top-notch craft growers who are passionate about the industry. We do product quality testing to ensure all of our recommendations are up to our standards so you don't waste your time and money to find the right product. What we look for when testing is; build quality, ease of use, correct product specifications, and lastly does the performance match the value. In this post we will explain the difference between advertised vs actual wattage, what light spectrum and PAR means, and finally we put everything we learned up against the CGE Max300 (SP1)
Your garden is finally all setup, exhaust is hung, pots are laid out, and air is moving. You have the best nutrients money can buy to make sure your first crop is a success. You purchase a grow light that looks perfect; reviews were high, output looks promising, and it was advertised for exactly what you were looking for. Did you make the right decision? Let us example to you some of the important information you need to look for before that final click.
This is how most companies advertise their LED grow lights by multiplying the number of LED diodes by the maximum output wattage (Theoretical wattage). Let's say the LED grow light you purchased was advertised as 1000 watts which looks very enticing! When you plug the product into your setup, you realize it's actually only consuming 150 watts!
The actual wattage
, or true watts is generally shown in the grow light’s specifications. This is how much wattage the light is consuming. The LED shows that it only uses 150 watts, which isn't nearly as good as the 1000W that was advertised. We as growers use actual wattage along with other grow light specifications (PAR) to determine the right size for our grow space.
Light spectrum is the different wavelengths of energy (light) that are measured using (nm) or nanometers
. Each nanometer is associated with a specific light colour. Confusing, I know - but this should help explain; the light spectrum starts with ultra violet (UV) which has a (nm) between 180-400 most of which is blocked out by our atmosphere. We then move into our visible spectrum
(what are eyes can see) which is between 380nm-750nm. This includes blue light (450-485nm) for vegetation growth
, green light (500-565nm), yellow light (565-590nm) and red light (625-740nm) for flowering
. We don't stop there - just because light isn't visible doesn't mean it isn't visible to the plant, this is where (IR) Infrared Light (700-1000nm)
comes into play. IR light is used in your TV remote to transmit signals, and in security cameras to allow them to record at night. They appear as being “off” but in reality, they are just not visible to our eyes.
or photosynthetic active radiation
is the amount of light the plants see to photosynthesize.
When measuring a lights PAR ratings, we use the measurement PPFD (photosynthetic photon flux density) to get the exact amount of PAR that actually makes it to the plant. A very basic guideline for how much PPFD a plant needs is as follows;
- 200-400 is great for seedling, clones, and mother plants
- 400-600 is perfect for early to late veg cycle
- 600-1000 is great for flowering
Can you have too much light?
It is possible to output too much light. At 1100 PPFD, this is what is known as the light saturation point. At this point you will see a decrease in photosynthesis and in turn either have to raise the fixture or start adding C02 to the grow space to allow the plants to thrive. Now you can understand why your LED grow lights need to be installed at a distance when growing to meet the guidelines above. Just because LEDs are advertised to run cooler than traditional growing lights, keeping the canopy too close to the fixture can result in “Light Burn”. Now let’s take what we just learned above and use the CGE Max300 (SP1)
as our test subject.
The CGE Max300 (SP1)
As we can tell by the name, the CGE Max300 grow light is advertised as a 300 watt fixture. With an inexpensive energy monitor we can find out what the actual wattage is. The total actual wattage of our CGE Max300 is 250w, which means it is consuming up to 83% of the advertised wattage, which is very good ratio! Next let’s look at the PAR ratings.
With the grow light height set to 18" from plant canopy, The PAR value in the dead center is 685 PPFD
, What this tells us is at 18" the center of your growing space is getting perfect amounts of PPFD for the late vegetation to early flower stage. The light will need to be lowered to achieve higher values when in full bloom. As you can see, the measurement lowers as the light covers over a larger area. This is important information to look at when purchasing the right size LED grow light for your grow space.
Looking at the CGE Max300 SP1
Light spectrum we can see the blue light for vegetative growth, high values of red light for flowering, and a great deal of infrared (IR) to be able to penetrate through the canopy and reach the root structures while creating larger leaves. This creates greater nutrient absorption, and stronger stem structures.
By reading this post, you now have learned the basic understanding of the specifications behind an LED grow light. Always research before you make the final purchase, no one wants to unbox a product to find out that it isn't performing how they advertised it would.
Derek Ryken is the Co-owner of TheBudLab
, which is a craft growing club focused on helping people grow successful legal Cannabis. They have a team of top-notch growers ready to answer questions with a live stream, forum, and chat to help you get the results you want.
TheBudLab – We are passionate about growing, let us teach you.