How do I choose the perfect LED?
To ensure that your investment in an LED grow light meets your cultivation and production goals, you need to know what manufacturers mean by PAR, PPF, PPFD, and photon efficiency to make an informed purchasing decision. However, these three metrics should never be used as sole variables to make a purchasing decision.
There are several other variables that need to be considered as well, we will explain these later on:
■ your goal: Are you germinating (seeds), are you growing seedlings, cuttings or mother plants; do the crops remain in the vegetative phase, or do they flower as well? Do you aim for the highest yields possible or do you have medicinal purposes in mind (we recommend spectrum control for the best medicinal endproducts)? The plantphase will mostly determine your final choice. Please read a more detailed explanation in section 3.
■ coverage area: The size of the surface that you want to illuminate used to determine the required wattage (to a large extend). Wattage used to tell you ''how much light'' would be emitted. This is not the case with LEDs (and lighting sources in general) as PPFD tells you how much usable light is actually emitted on the surface of your plant(s). Please read a more detailed explanation in section 2.
■ the spectrum: Determines for what kind of plant(s) and for which phase(s) of the(se) plant(s) the fixture is best suited (for Germination, Clones, Motherplants, Vegetative and/or Flowering). Every wavelength / color has a different effect on plant development and photosynthesis. Plants are in need for different wavelengths / colors in different phases (germination, cloning, vegetative and flowering) and ratio's. Please read a more detailed explanation in section 3 or the complete information here: https://ledbypassion.com/spectrum.
■ your personal health: Does your health allow you to work on your knees, to bend and to ''SCROG'' for example? Does it allow you to lift heavy lights (15 – 20 kg) or do you prefer to work with lightweight LED bars?
■ your growing method: We recommend different lighting systems for several growing methods; some LED systems need to be used at a close hanging distance (the distance from your light to the top of your plants) and other lights are used at a high hanging distance. So it depends on the method of growing you prefer.
■ your grow environment: Temperature, humidity, air circulation, background noise and your living situation for example (HVAC) can influence your final choice. For example: you don't want any noise (caused by active thermal management) if you are growing in your bedroom.
All factors need to be taken into consideration to select the most appropriate system based on your cultivation and business goals, and the take home message is that PPF, PPFD, and photon efficiency are the proper metrics used by scientists and industry leading horticulture lighting companies. If a company does not provide you with the correct metrics used for horticulture lighting, they should not be selling horticulture lighting systems, and you will not be able to verify the true efficiency of their system.