Light Factors That Are Needed for Your Indoor Plants

Light Factors That Are Needed for Your Indoor Plants - Explanation of what is PAR, PPF, PPFD, PBAR, DLI, and EFFICACY.

It’s really a great thing to have high-end indoor lights for your growing business because it will assure you to get high-quality yields. But, the main question is “Are you aware that there are light factors that your indoor plants needed?”, knowing these light factors are very essential in order for you to be informed and always ready to take the next move in case of emergency situations. Thus, reading this post can be a big guide for you in knowing the light factors that are needed for your plants. You will be able to learn the definitions, and roles of PAR, PPF, PPFD, PBAR, DLI, and EFFICACY in your plants. You can also see in this post the list of some of the top LED grow lights in today’s industry that will surely fit in your growing business!


PAR or also known as Photosynthetically Active Radiation is the band of wavelengths between 400nm and 700nm. This range of electromagnetic radiation is often used by the plants in order to have photosynthesis, in fact, the mid-400s (blue) and mid-600s (red) is considered to be the most efficient in absorbing wavelengths.

It’s said that if a plant receives a higher PAR it will results in a fast growth and eventually become larger plants. Thus, it has been always pointed out that light intensity is more significant than the spectrum.

In order for you to understand clearly about what’s the latter information is all about, let’s use an HPS grow light spectrum as our example. Today, there are a lot of HPS spectrums which belong in the deep orange and yellow part of the curve containing peaks at 600nm or below. These spectrums are not suitable for photosynthesis, yet HPS grow lights are still known to be the best flowering bulb/spectrum for many years.

Now, this leads to your question “Why does HPS grow lights still in-demand to the public knowing that their spectrums are not suitable for photosynthesis?” Yes! It’s right that HPS bulbs lack in the spectrum, BUT they truly make up in intensity. That’s why 1000-watt HPS bulbs are considered to be better than some other LEDs who are sold with a marketing line of a“1000-watt replacements” in the market today because they can outperform this kind of LEDs.

Just an important reminder for you! Most people thought that the term PAR is a quantity of light. Well, this is just a mere misconception because PAR is not a quantity of light, but rather a quality of light. Some manufacturers and growers usually misunderstand this term and they refer PAR as a measurement when in fact, it’s not.

Thus, always remember that Photosynthetically Active Radiation is the only light intensity measurement that absolutely acceptable to your plants. Don’t ever use wattage in order to know the intensity of light output of your LED grow light! Because wattage only includes how many watts does your fixture is consuming. Wattage can also be the total amount of LED watts, however, this is not that important and just often used as a marketing tool to inflate the fixtures power and light intensity.

LUMENS and LUX as Grow Lighting Intensity Measurements, ARE THEY IMPORTANT?

To those who are not yet familiar with these terms or already encountered it, but don’t know the definition is, introducing Lumens and Lux these terms have been always used as a grow lighting intensity measurements.

Lumens and Lux are for environmental white light that’s used in the home, commercial, and industrial applications, however, they are not significant to any type of grow lighting because of the following reasons:

  • Lumens are the quantity of visible light emitted from a source and with peak sensitivity in the green portion of the spectrum. Thus, the more lumens, the brighter the light source.

  • Lumens are weighted for human eye sensitivity since their eyes are most sensitive to green light (500nm to 550nm). Although, luminous flux can be applied for humans, but not in the case of plants because they are most sensitive to blue and red light.

  • In addition, even if humans may see a light source as “bright”, but plants cannot equal that ability of humans to see that immense effect. In short, lumens are for humans, and it’s not a measurement for how much light is available for photosynthesis.

  • Both of it can greatly underestimate a LED fixture’s PAR, especially when of the blue and red with no green spectrum. Thus, Lumens and lux are just as unimportant as using the number of watts that the fixture draws from the wall to determine whether the fixture will provide enough light for your plants.


PPF is also known as photosynthetic photon flux. This light factor measures the total amount of PAR that is produced by a lighting system per second. Did you know that PPF is taken from a specialized instrument? You heard it right! because this measurement is absolutely taken from an integrating sphere which is a specialized instrument that captures and measures all photons emitted by a lighting system.

Moreover, the unit used to express PPF is micromoles per second (μmol/s). This is considered as a second most important way of measuring a grow lighting system, however, you must take note that PPF does not all about how much the measured light actually emitted into the plants, but this can be an important metric in calculating the efficiency of a lighting system at creating PAR.


PPFD is also known as photosynthetic photon flux density. This is used to measure the amount of PAR that’s given to the plants, to make it clearer PPFD the number of photosynthetically active photons that fall on a given surface per second.

It is also named as a ‘spot’ measurement of a specific location on your plant canopy. Thus, it is measured in micromoles per square meter per second (μmol/m2/s). In case you want to find out the true light intensity of a lamp over a designated growing area (e.g. 4’ x 4’), it is important to take note that the average of several PPFD measurements at a defined height are taken.

Just a reminder! Most lighting companies that only publish the PPFD at the center point of a coverage area usually overestimate the true light intensity of a fixture. Therefore, it’s important for you to know that a single measurement does not tell you everything, since grow lights are usually brightest in the center, with light levels decreasing as measurements are taken towards the edges of the coverage area.

In order for you to prevent scams from the manipulation of PPFD data done by lighting manufacturers remember these essential things:

  • Measurement distance from the light source (vertical and horizontal)
  • Number of measurements included in the average, and the min/max ratio


PBAR is also known as Plant Biologically Active Radiation flux and it is similar to PPF, except that it only takes into account the wavelengths from 350nm to 800nm. The units are in μmol/sec. and this measurement is merely based on the observation that plants have photosensitive pigments outside the 400nm and 700nm range.

Thus, the PBAR flux measurements are slightly higher than the PPF since it involves taking the UV and IR photons into consideration, assuming that the light source contains these wavelengths.

Lastly, PBAR flux is considered to be an important metric since medical plants show sensitivity to the wavelengths outside of the typical PAR range and on the other hand, many LED grow light manufacturers include these wavelengths in their spectrums. If you’re wondering where to find this metric, well it’s truly understandable because it’s really rare to find it on many manufacturer’s specification sheets, let alone PPFD readings.


DLI is also known as Daily Light Integral and it’s used to measure the total number of photosynthetically active photons that they are absorbing each day. This is measured in moles per m2 per day, or mol/m2/d. In other words, the sum of the PPFD measurements is taken over a 24 hour period. Take note that the total amount of photons that strike the plants leaves during the daily photoperiod is the driving factor on how quick and efficient that the plant can make sugars to drive cellular processes.

Moreover, a minimum DLI is required among plants for proper growth and flowering. However, if you put too much light on your plants it will, unfortunately, results to bleaching and leaf burn since the plant’s internal processes don’t have the ability to handle with all of the extra incoming light.

Did you know that the DLI on the surface of our planet can range from 5 to 60 mol/m2/d depending on the time of year, day length, latitude and cloud cover? You heard it right! The reason behind it is that the sun at its brightest produces about 2000 umolm2/s. However, when it comes to medicinal plants grown outdoors these plants cannot absorb the full 2000 umol/m2/s all throughout the day.

Meanwhile, morning and evening PPFD readings are much lower because the average PPFD throughout the day might not even exceed half of this level. Just reminding you that choosing LED grow light for your plants is a very crucial and important decision and also don’t get overwhelmed of the usage of light because “Too much light is not really a good thing.”

If you’re worried about DLI for your indoor plants, don’t be! Although the lighting intensity is a factor that depends on the chosen light source, the photoperiod on the other hand, is already set for 18 hours and 12 hours for vegetative stage and flowering stage, respectively. Thus, you only need to consider the PPFD when planning out their grow setup.

Furthermore, you shouldn’t take DLI for granted especially for those who are greenhouse growers because DLI is very important in seasonal latitudes especially when planning out supplemental lighting during these seasons who only produce less light like late autumn, winter, and early spring in most areas. Take note that DLI in greenhouses rarely exceeds 25 mol/m2/d in greenhouses, thus you need more additional lighting.

Here’s an example equation and formula for you in order to properly calculate the DLI:

All you have to do is to multiply the PPFD reading by the photoperiod and divide by 1,000,000. Thus,

  • DLI = PPFD x (3600 x photoperiod) / 1,000,000
  • PPFD: umol/m2/s
  • 3600 seconds in one hour
  • Photoperiod is in hours
  • 1,000,000 umols = 1 mole
  • Example: 800 umol/m2/s x (3600s x 12h) / 1,000,000 = 34.6 moles/d

Photon Efficacy

Photon Efficacy simply refers to how efficient a horticulture lighting system at converting electrical energy into photons of PAR. Today, a lot of grow light manufacturers use the total electrical watts or watts per square foot as a measurement or metric to describe light intensity.

However, these metrics don’t actually derive you into something since watts are a measurement in describing the electrical input, not light output. And so, if the PPF of the light is known together with the input wattage, then, you can able to calculate how efficient a horticulture lighting system in converting electrical energy into PAR.

Thus, to remind you always remember that the unit for PPF is μmol/s, and the unit to measure watts is Joule per second (J/s), therefore, the seconds in the numerator and denominator should be canceled out, and the unit becomes µmol/J. Remember that the higher the number is, the more efficient a lighting system is when it comes in converting electrical energy into photons of PAR.


It’s very important to have a clear decision-making capacity especially in this kind of business that’s why if you want your investment in purchasing your LED grow lights to not be wasted then, you must really know first the PAR, PPF, PPFD, PBAR DLI, and EFFICACY in order to meet your cultivation and business goals.  On the other hand, these metrics are not alone the factors you must consider but also be aware of several other variables like the form factor and coefficient of utilization (CU) that needed to be considered as well.

All of these factors must be used in order to choose the most accurate systems based on your cultivation and business goals. Additional trivia for you!  PPF, PPFD, and photon efficiency are the proper metrics used by the scientists and industry-leading horticulture lighting companies. So BE AWARE if a company does not give you with the right metrics that are used for LED grow light, then they should not be selling one of them, and you will not be able to verify the true efficacy of their system. Just be keen and wise enough in every decision you’ll make before purchasing any products!


NextLight Mega Full Spectrum LED Grow Light

Do you want to have a grow light that is very similar to natural sunlight and thus works well throughout all grow cycles? Then, NextLight Mega is what you’re looking for! NextLight spectrum is.

The Nextlight Mega dubbed as the “Best Full-Spectrum White LED Grow Light” which is released in 2016 is the replacement of the 1000 watt double-sided HPS which draws only a maximum of 650 watts. This product uses only half the energy and 75% less heat than a standard DE 1000 watt HPS grow light.

Thanks to the competence and quality of Mega’s LED technology, you can finally save time and money with this product. With its 100,000-hour lifespan, you can run these lights for over 11-years with continuous 24/7 use. It will also give you better results by helping you cut your energy costs in half and stop bulb replacements costs.

When it comes to spectrum, Nextlight Mega was made to closely mimic the natural spectrum of the sun giving your plants the absolutely optimal conditions without the high energy requirements and heat output found in a 1000w HPS light. It has also a full white light spectrum that is more convenient and cost-effective for you to use. You don’t anymore need to switch between veg and flowering light because of the product’s single light that can surely take your plants from seed all the way to harvest.

The NextLight Mega is a product from the USA and a top choice for commercial grows because of its perfect fixture for tents, grow rooms, or commercial grows.  It measures 37" x 37" in which the wide part and thin profile of it allows the heat to dissolve without additional heatsinks or fans. It also helps in creating a more even footprint that has no hotspots or low PAR readings.

Overall, NextLight Mega’s coverage area is the largest among 1000w equivalent LEDs. Its watt is considered to be the most output per watt among all full-spectrum LED lights and it has a deep canopy penetration that’s equal to a 1000 watt DE HPS bulb. You can also assure that it has a low heat output because it has no internal fans, so it’s completely silent. Lastly, NextLight Mega has also the longest hours among LED fixtures rated for 100,000 hours.

Incredible service and incredible product! Who could ask for anything more!★★★★★ 5/5


  • Wattage draw: 650W (replaces comparable 1000 watt DE HPS)
  • Coverage area: Up to 5’ x 5’ Flower (25 sq. ft.) or 7' x 7’ Veg (49 sq. ft.)
  • PPF: 1400 umol/s
  • Spectrum: 3000K and 5000K (4000K average) White Diodes (Take your plants from seed to harvest with a single light)
  • Operating Voltage: 120-240 (comes with both 120v and 240v cords)
  • Warranty: 5-year full


California Lightworks SolarSystem 1100

Are you already annoyed with your large energy consumption? And wanted to replace your current 1000 watt HPS system? No need to worry because California Lightworks SolarSystem 1100 is here to help you!

The SolarSystem 1100 (SS 1100) dubbed as the “Fully Customizable Spectrum with Controller LED Grow light” is the most powerful light we’ve ever made. At the beginning of 2018, the California Lightworks take the SolarSystem series efficiency into the next level by 25% (from 1.55 umol/j to 2.2 umol/j). This product is an upgraded version featuring UVB light bars on each side of the grow light.

SS1100 has a fully customizable spectrum, timing, dimming, and scheduling control with the optional controller. This is a perfect setup for fans of the discontinued SolarStorm 880 since SS 1100 will produce the same yield as a 1000 Watt HPS or MH light with an average of 40% less energy usage. Using its advanced spectrum control system it will further increase efficiency and yield compared to old fashion fixed spectrum lighting.

Just like the SS50, the SolarSystem 1100 has also the California Lightworks' LED fixtures that are plug and play and very light in weight so installation is easier. Add that to the advantage of never changing a bulb and you have the industry’s most efficient lighting system.

Overall, SS1100 has a Top-bin 5 watt Osram diodes that have a high power for penetration and intensity that beats HPS. It has also a fully customizable spectrum using an optional controller and a Veg and bloom modes that use less power during veg that will help you save money.


  • Power Consumption: 800 Watts
  • Light Output: PPF 1284
  • Spectrum Control
  • Auto Voltage: 90 - 227v
  • Maximum Current: 6.6A @ 120V, 3.3A @ 240V
  • Frequency: 50-60 HZ
  • Heat Output: BTU 2550
  • Operational Temperature: 0-107 F
  • Power Factor: > 0.95
  • Coverage Area: Bloom 4x4
  • Coverage Area: Veg - Up to 8x8
  • LED Lifetime Rating: 50 000+
  • Thermal Management: Active
  • Dimming 3 Channel 0%-100%
  • Warranty: 5 full-year


Black Dog LED PhytoMAX-2 1000 Full Spectrum Plant LED Grow Light

Are you looking for a LED Grow light for your smaller grows that will help you save energy and space without sacrificing light quality or intensity? Then, the Black Dog LED PhytoMAX-2 1000 Full Spectrum Plant LED Grow Light is perfect for you!

The PhytoMAX-2 1000 will outperform any other equal-wattage LED grow light in the market! It uses 420 high output 5-watt diodes for high light intensity that is very crucial for canopy penetration, which is what some LED manufacturers are lacking in their products.

Research has proven through the independent testing of a spectroradiometer (a device designed to measure the spectral power distribution of a source) that the PhytoMAX has the largest footprint among any LED grow lights. The PAR footprint in the PhytoMAX is the most even coverage which eliminates leaf burn and hot spots.

At 1050 actual watts and 1602 μMol/s total photon flux, the patent-pending PhytoMAX-2 1000 LED grow lights are perfect for smaller grows where it's important to save energy and space without sacrificing light quality or intensity. Thus, it produces a superior yield with higher quality flowers all while saving on electricity, cooling and bulb replacement. Plus it has also a free pair of ratchet hangers included with every fixture!

You will never say no to this product because PhytoMAX-2 series is engineered to deliver the most powerful and reliable, truly full-spectrum (365-750nm, UV to NIR) LED plant grow lights! The PhytoMAX-2 1000 uses only the highest-quality, latest-technology, top-bin LEDs to deliver Black Dog LED's proprietary full-cycle Phyto-Genesis Spectrum evenly over the entire footprint, with unprecedented PAR levels, canopy penetration, and yields!

You’re investment in this light will not be wasted because of its fast & proven ROI! With a 6-12 month average return on investment, PhytoMAX is the best value per watt of any commercial LED grow light. Assuming a harvest every 10 weeks, the Black Dog LED light will pay off the cost difference between and an old-fashioned HID light in less than 5 months. This is even faster than through increased yield alone! And, when you combine both quality and yield, Black Dog LED lights become much more affordable than traditional HIDs.

Overall, take note that Black Dog LED doesn’t only have the highest PAR values, largest footprints, and most reliable LED grow lights available in the grow light industry, but also all Black Dog LED lights (including the PhytoMAX Series) come with an industry-leading, 5-year warranty!

HUGE Thank you to Rightbud for the amazing price and awesome LED. ★★★★★ 5/5


  • Max. Flowering Footprint: 6.5' x 6.5'
  • Max. Vegetative Footprint: 8' x 8'
  • Shipping Size: 28" x 28" x 12"
  • Product Dimensions: 21" x 21" x 7"
  • Shipping Weight (lb.): 56.0000
  • Weight: 53lb (24kg)
  • True Wattage: 1050w
  • LED Wattage: 2,100w
  • Certifications: ETL, CE, FCC, RoHS
  • Mean Time Between Failure: > 50,000 hours
  • Number of LEDs: 420
  • Amp Draw: 8.8A~4.4A (@ 120/240v)
  • Cord Length: 8 feet
  • Voltage: AC 100V~250V
  • Work Frequency: 50~60 Hz
  • Power Factor: > 0.98
  • Operation Temperature Range: -4~104 °F
  • BTU: 3581
  • Fans Expected Life: 70,000 hours
  • Warranty: 5 years


Viparspectra V1200 LED Grow Light

Remember the old models of VIPARSPECTRA series? You’ll be amazed of the newest generation of its product, Welcome to the next generation of VIPARSPECTRA V1200 LED Grow Light! If you want a grow light that’s fit for your indoor plants veg and flower at all growth stages then, you should grab this one now!

Welcome to the next generation of VIPARSPECTRA V1200 LED Grow Light, with its full spectrum layout and upgraded aluminum cooling heat sinks that is ideal for all kinds of indoor plants veg and flower at all growth stages.

VIPARSPECTRA V1200 LED Grow Light is scientifically engineered to keep the balance of the PAR/Lumen Output and Coverage. The secret of this product’s success is the optimal full spectrum which provides plants Veg and Flower all stages with everything they desire from the natural sunlight.

This is so much better and far from traditional 1000 watt HPS/MH for this consumes only 524 watts! Perfect for a 4x4’ growing area at 24” height (Max coverage 5x5’). The product has already have an upgraded 4.72” fans and big aluminum cooling heat sinks (0.8” height) that are easy for heat dissipation.


  • Input Voltage: AC85-264V
  • Life Span: ≥50,000 hours
  • View Angle: 90 degree LED
  • Working Temperature: -20 to 40℃
  • LED Quantities: 240pcs 5W LEDs
  • LEDS Composition: Full spectrum
  • Dimensions: 19.2x19.2x3 inches
  • Item Weight: 21.6 lbs
  • Power Consumption: 524W
  • LED Power: 1200W
  • Max Coverage: 24" Height 5x5ft
  • Core Coverage: 24" Height 4x4ft
  • Frequency: 50-60Hz
  • Lifespan: 100,000 hours
  • Warranty: 3 years

Package Includes

  • 1 x 1200W
  • 1 x Hanging Kits
  • 1 x 6ft Power Cord (US Standard 110V grounded 3 prong plug)


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