White Vita LED Bulb Plant LightShop Now
February 12, 2021 5 min read
Photo by Callie England
Equation to determine DLIThere is the equation and as you probably expected it has a lot going on. However, it’s easy to break down. PPFD is the photosynthetic photon flux density which is fancy science talk for the amount of photosynthetically active photons that fall on a surface of a plant in a certain amount of time. Photoperiod is the amount of time a plant needs in sunlight to properly grow. The rest is just math conversions to get the rates for the equation. The most important part of this equation is photoperiod. Without knowing the photoperiod, you are just guessing at the optimal DLI for your plant. If you know that your carrots are long day plants or your soybeans are short day plants, you will be able to properly calculate your DLI for each plant and thus give your plants the best light. DLI is like a proportion. A high intensity of light (PPFD) with a short-time frame will have the same DLI as a low intensity light with a long-time frame. The secret is finding the perfect balance for your specific plant.
The PPFD of this light fixture will be higher for the dark green leaf than the light green leaf. This is because the dark green leaf is located centrally in this beam of light and closer to the fixture. An increased PPFD will result in a higher DLI for the dark green leaf over the same time frame than the light green leaf. Image created on biorender.com
Plants growing in a greenhouse will rarely have a DLI over 25 due to the opaque windows. This is important to keep in mind if you grow in a greenhouse, you may need to add light fixtures if you need a higher DLI. Sourced via https://pixy.org/205801/All you need to do is get it in a good range. If your DLI is too low, you can have slow rooting, delayed flowering, weak branching or low flower number. Your plant will be weak as it is unable to produce lots of plant matter. If the DLI is too high it can result in leaf burn or drying out, which will be detrimental as your plant will lose its color while also losing the capability to produce more plant mass. The Aspect and Highland Plant lights come equipped with timers for you to plan out the proper DLI for your precious plants, to make sure they are getting the light the do (and don't) need.
Sign up below!