What is PPFD and why is it important

PPFD or photosynthetic photon flux density. PPFD measures the amount of photosynthetically active photons that fall on a square meter area per second (PAR).  PAR spectrum is the visible light wavelength that fall between 400 and 700 nanometers. In order to understand how a plant grows, light itself must be understood. Particles of light aka photons are measured in different wavelengths (NM). Well how come I cannot see them? You can see them in certain reflections, also rain particles help in the visualization of these wavelengths aka rainbows. Hence the reason you see the different colors when looking at a rainbow. What you are seeing are actual individual massless photons coming down at the speed of light. 400-700nm can be absorbed by the plants pigment chlorophyll. The light this pigment mostly absorbs is blue and red. The light absorbed by the chlorophyll is used to fuel a process called photosynthesis.  

You as a grower want to optimize your growth. This means using a light source that has enough energy for what you are trying to produce. Which is why I am typing this article, so you understand the importance of measuring and calculating your lighting needs. Lights are rated by a couple different terms that vary in importance PPFD, PAR and watts. Watts are important because it is important to know how much energy you are using to achieve the amount of PAR or PPFD necessary to achieve desired results. Watts are also important in calculating the amount of yield you will harvest.

I hope this was able to help you in the search for the perfect grow light. Come grow with us!

And for the haters…

Lighten up we’re gardening here



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