speaking of light again i thought it was time to try explain how to use all these light figures ive been throwing around. So with that in mind ive produced a bit of a sheet and hopefully an easy visual representation of what we are talking about in regards to the intensity of light (PPFD) and the amount of light a plant needs in a given light period per day (DLI)
So let start with the infograph and then ill try to break down the info to give you the best chance of using it to your advantage
We have plotted the PPFD against the hours of light in a day to help show the area of DLI we are looking to achieve for "optimum" photosynthesis. Optimum is kind of a key word here and you will notice there is a large area to the top right of the chart which is in orange and deeper orange. this is to indicate a DLI which is very likely to require the addition of CO2 to maintain the optimum photosynthesis, with home growers in mind and most venting enough air to make CO2 addition ineffective in regards to cost vs return for the amount of air being removed that the chart has focused on DLI which shouldnt require additional environmental controls
The Large yellow area is to show what would be considered below optimum lighting, but this range of light can be greatly utilized while starting young plants and through early veg while leaf cover isnt complete for the use of high PPFD
The very bottom end low end is to represent day periods as well as intensities which are considered inappropriate for our uses with our plant, but if you have any experience in these ranges please feel free to shed some light on the subject (pun intended)
Now that we have explained the outer limits of the chart; the green area is our focus for during peak both Veg and Flower phase. The interesting balance and personal use of this chart comes about when we begin to balance our chosen lights on period duration with our target DLI. For example if we are aiming for a low end DLI as we are in mid veg but havent fully established our leaf canopy a target DLI closer to 20-22 at a duration of 16-18 hours (PPFD of 400) would likely be more optimum than attempting to rush plant with 64.8 mole DLI running at full 1000 PPFD for the same duration
Conversely when we approach flower and a photo-period of 12/12 of less our DLI may be as high as 48+ mole which we then need to offset by raising PPFD 1150.
I hope these example help you to decide how to use your lighting power appropriately saving you some running costs and easing the worry the comes with all the figures associated with LEDs. its all really simple when we break it down
If you have any further info please feel free to share and as always; any further questions please ask
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