Led Grow Light Distance Chart

Maintaining proper distance between plants and grow lights is crucial for the healthy growth of the crops. Cannabis plants use the energy they capture from the grow lights to maximize yields by growing bigger buds, and healthier stems. In this case, you need to ensure that the plants get adequate light without causing any burns to the plants or overheating.

Maintaining a LED grow light distance chart that helps you not go overboard when monitoring light levels is the best way to do this. Plants go through several growth stages before harvesting. The stages all need light for proper growth, but light outputs and distance calculations differ from one stage to the next.

Lighting systems come in different forms that include LEDs, LECs, HPS, CFLs, and T5s. HPS, LEDs, and LECs come with more lighting outputs and are the best for the most potent buds and highest yields. Cannabis growers prefer using LED grow lights because they come with features that provide specific light spectrums that target all the plants’ lighting conditions.

Led Grow Light Distance Chart

LED grow light technology also provides more cannabis yields over a shorter period than traditional lighting systems do. Other benefits that make LED grow lights a favorite with cannabis growers include lower power consumption and forward heat reduction.

Even with the immense popularity and benefits of using LED grow lights, it is vital to keep a healthy distance between the lights and the plants. Doing this helps achieve the desired results of healthy flowers, the uniform spread of leaves, and the right height.

In this article, we guide you through the appropriate distance levels to maintain between the LED grow lights and cannabis plant canopies.

-$9.00 SALE OFFBestseller No. 1
GooingTop LED Grow Light,6000K Full Spectrum Clip Plant Growing Lamp with White Red LEDs for Indoor Plants,5-Level Dimmable,Auto On Off Timing 4 8 12Hrs
15,105 Reviews on Amazon
GooingTop LED Grow Light,6000K Full Spectrum Clip Plant Growing Lamp with White Red LEDs for Indoor Plants,5-Level Dimmable,Auto On Off Timing 4 8 12Hrs
  • 6000K White Light - equipped with 10 Red + 74 White LEDs, this growing Lamp is similar to the full-spectrum sunlight at noon,that is professionally designed for indoor garden plants.Moreover, its color rendering index is as high as 95, the light is soft and flicker-free, which is very suitable for reading lamp
  • Timer Function & Multiple Settings - this growing light offer the timer function with 3 options that is 4Hrs or 8Hrs or 12Hrs, it is based on a 24 hour cycle from the time you set the timer.For example,when keeping power ON, if you select 8 Hrs,it will turns ON for 8 hours per 24 hours.The other two timer settings are the same.
  • Easy to Install - with flexible Gooseneck & strong clamp,it allows you to place the growth light in any direction to provide the best lighting angle for your plants,meet the cover around the plant.Powered by USB or AC Power Plug
  • High Efficiency LED Lamp - as for LED power draw this seedling lights just comsume about 10watt and is equivalent to a 50W Halogen Bulb.Estimately monthly cost roughly $2 in electricity (12 hours a day). It is a great gift if you growing some small house plants.
  • 【365 Days Worry-free Warranty】GooingTop service team offer 365 days warranty and 24h friendly customer service. If there are ever any issues about the product, please feel free to contact us and we will send you a new replacement or full refund.
Bestseller No. 2
LBW Grow Light with Stand, Full Spectrum 150W LED Floor Plant Light for Indoor Plants, Grow Lamp with On/Off Switch, Adjustable Tripod Stand 15-48 inches
  • 2021 Upgraded Design - Adjustable tripod stand extendable from 15 inches to 48 inches , just set it at desired height for your preferred use, you can stand it on the floor and adjust the gooseneck at the desired angle according to the needs of the plant.
  • Full Spectrum - Compact grow light with high quality super bright LEDs, full spectrum 390nm-730nm, including White(3500K&6500K)Red&Blue. Plants can get the spectrum they most desire from this grow light. It's suitable for all stages of growth such as seedling, germination, vegetative flowering.
  • Energy Efficient - 30w power draw replace 150W HPS or HID grow light with only 30W consumption, saving your electric bill. Good for indoor use.
  • Easy to Install - Within just one minute! Screw up the tripod, gooseneck and the plant light, adjust the height and angle, done!
  • Widely Used - Widely apply to family balcony seeding/breeding, gardening, flowering, potted plants, especially tall and large plants. 12 months warranty plus 30 days satisfaction or return guarantee, 100% money back. Contact us first if any issues and we will make it OK.
Bestseller No. 3
Barrina Plant Grow Lights, 4FT 5000K Full Spectrum Daylight White, 252W(6 x 42W, 1400W Equivalent), T8 LED Grow Light Strips, Growing Lamp Fixture, Plant Lights for Indoor Plants, Greenhouse, 6-Pack
98 Reviews on Amazon
Barrina Plant Grow Lights, 4FT 5000K Full Spectrum Daylight White, 252W(6 x 42W, 1400W Equivalent), T8 LED Grow Light Strips, Growing Lamp Fixture, Plant Lights for Indoor Plants, Greenhouse, 6-Pack
  • 5000K White Full Spectrum LED Grow Lights - Barrina T8 grow lights 4ft provide indoor plants with full-spectrum sunlight replacement. It provides the most reasonable grow light wave based on the ratio of the absorption of the plants. Best for plants seeding, growth and bloom.
  • Super Bright and High PPFD - Consuming only 252W with 1152 LEDS totally, replace 1400w general grow light bulbs. Over 95% light energy can be absorbed by plants. 5000K white color temperature makes your eyes feel comfortable. It works extremely well for your plant grow tents, plant grow shelves, seedling cultivation, hydroponic rooms, greenhouses, etc.
  • V-shaped Reflector Design - The indoor grow lights efficiency can be increased by 17~20% with reflector, providing you with best light intensity. The shell of our LED plant growing light was made of 100% aluminum which provides the high-efficiency heat dissipation. Ensuring the longer service life of the led chips.
  • Easy Installation - With included tape, clips and cable ties, you could install the lights by yourself in minutes. Plug and play, and you could link up to 6 grow light strips in a series, saving your installation cost and time.
  • What You Get - 6 x Barrina Indoor Plant Lights, 3 x Power Cords with ON/OFF switch, 5 x Connecting Cords(48''), 6 x Small Connectors, 24x Installation Clips, 12 x Tapes, 24 x cable ties.
Bestseller No. 4
KEELIXIN Grow Lights for Indoor Plants,5 Heads Red Blue White Full Spectrum Plant Light with 15-60' Adjustable Tripod Stand, Indoor Grow Lamp with Remote Control and Auto On/Off Timer Function
3,530 Reviews on Amazon
KEELIXIN Grow Lights for Indoor Plants,5 Heads Red Blue White Full Spectrum Plant Light with 15-60" Adjustable Tripod Stand, Indoor Grow Lamp with Remote Control and Auto On/Off Timer Function
  • Comprehensive and Effective Spectrum: this 5-head grow light contains 3 supplemental light modes:1. warm white(3000k), similar to sunlight, simulate nature environment for plants; 2. Red(660nm)+Blue(460nm): promote photosynthesis, rooting, germination, blooming, fruiting; 3. Red+Blue+White(380nm-780nm), provide universal full spectrum which can meet the light conditions your plants need most in different stages
  • Floor Grow Light with Adjustable Stand: equipped with sturdy tripod stand which can keeps the grow light stable and not wobbly, easily adjusted from 15” to 63”, with 360 degree flexible gooseneck. 5 heads design can provide a much wider coverage for indoor plants than original ones, allows for every plant to receive ample light it needs to live
  • Remote Function & Auto On/Off Timer : both have line-in controller and RF controller, as you can remotely control the plant light which is convenient to operate and can effectively protect your eyes. Auto circular memory timing function has 4/8/12H modes for you to choose, the plant light will turn it on by itself everyday as your setting, even you're on the travel, these grow light strips will still take good care of your plants every day!
  • 10 Level Brightness: has 10 dimmable brightness levels, low light for delicate plants and high brightness for strong plants, you can randomly switch it to the most suitable brightness for your plant growth, helps your plants grow 5 times faster and more flourish than natural
  • Designed Specifically for Plants: our grow light is made of an aviation-grade heat sink and high-quality aluminum shell, create an excellent heat dissipation to reduce light loss and extend to 50000-hour long life span, perfectly suitable for balconies,greenhouses,darkroom,office and etc., especially when the plant needs extra light when raining,snowing,dark indoor and so on, will give your plants considerate care
Bestseller No. 5
LBW Plant Grow Light, Full Spectrum Grow Light for Indoor Plants, 270 LEDs Growing Lamp with Auto On/Off Timer 4/8/12H, 3 Lighting Modes, 10 Dimmable Levels, Suitable for Plant Growth, 2 Pack
  • Wider Cover Area Plant Light: Our 2 pack 11.8'' * 3.9'' plant lamps are made of pure aluminum alloy with excellent heat dissipation, it can cover a wider illumination area and more plants, magnificently improve the light coverage and your planting efficiency. Your plants great partner!
  • Full Spectrum Bright Grow Lamp: These new full spectrum grow lights feature with 270 LEDs which emit all wavelengths from 380nm to 780nm, similar to natural sunlight, with higher PAR output, and provide uniform light for your plants. They are suitable for all plants at all growing stages, such as herbs, succulents, orchids, etc. Help your plants grow vigorously year-round.
  • 24-hour Timing Cycle Function: These LED grow light strips have a circular memory timer function and can be set to 4, 8, 12 hours as plants’ needs. When it is supplied with uninterrupted power, it can automatically turn on/off and no more manually operation everyday. Even if you go on vacation or work, the light panel will take good care of your plants, very easy & convenient!
  • 10 Dimmable Options & 3 Lighting Modes : The grow lights have 10 levels of dimmable options:10% - 100%, saving electricity while also ensuring the light needs of plant growth. They also has 3 lighting modes - one light on, the other light on or both lights on, allowing you to controll the light coverage freely. Give your plants better care by giving them the proper light intensity they desire!
  • Simple Design & Easy to Use: These thin plant light panels come with double-sided tapes and twit ties. Minimalist design fits various fixtures and surfaces. Specially designed for plant lovers who own shelves, bookshelves, cabinets, glass greenhouses, and so on. Hidden installation is more suitable for home decoration.

LED Grow Light Distance Chart

The chart below outlines the distance between LED grow lights and plants during the vegetative and bloom phases depending on the wattage levels.

HID WattageVegetative DistanceFlowering DistanceSpectrumLumensSize (inches)Weight
200 W12”-20”8”-12”380-780 nm960011 x 7.9 x 1.82.8 Lbs.
250-400 W16”-30”16”-18”380-780 nm1255011.8 x 6.4 x 24.5 Lbs.
550-650 W24”-30”16”-20”380-780 nm1520014.9 x 9.4 x 4.45.35 Lbs.
600-800 W32”-36”18”-22”380-780 nm1563014.0 x 9.0 x 3.54.75 Lbs.
900-1000 W36”-42”18”-24”380-780 nm2221614.2 x 13.2 x 2.46.57 Lbs.
1200 Watts30”-36”18”-24”380-780 nm3896613.78×9.84 x 2.26.72 Lbs.
1500 Watts30”-36”24”-30”380-780 nm4251215.75×8.39× 2.379.2 Lbs.
2000 Watts26”-30”18”-24”380-780 nm4966539.21×9.97× 3.547.85 Lbs.

Other Grow light distance chart


Besides LED grow lights, CFLs and HPS grow lights are also popular with some cannabis farmers. For cannabis growers that choose to use these lights instead of LED grow lights, it is only fair to show the distances to maintain between the light and canopy depending on the wattage.

WattageCFL (inches)HPS (inches)


31518-20 inches (45-51 cm) or more
63024-26 inches (60-66 cm) or more

How To Measure LED grow Light for Cannabis Plants

How To Measure LED grow Light for Cannabis Plants

LED grow lights come with different heat intensities and brightness levels depending on the wavelength and wattage. Plants absorb the light that helps with their growth process. Any extra heat from the lights causes damage to the plants’ foliage and the growers considering how much they put into the process.

The most basic way to measure the intensity of the LED grow light is by using the hands. If the heat is not bearable, enough for your skin, then it could also mean that it will be unbearable to the plants. If the dorsal side of your hand feels comfortable under the lights, it means that your plant canopies will feel comfortable too.

Besides the hand method, you can use the PAR and PPFD methods to measure the light intensity. Many cannabis growers do not know how to measure grow light for their plants irrespective of the lighting systems using the par and PPFD methods. The first step would be to understand the definitions of PAR (Photosynthetically Active Radiation and PPFD (Photosynthetic Photon Flux Density)

PAR is the light that cannabis plants or any other type of plants see. PAR is also the light plants use for photosynthesis with ranges from 380 nm to 780 nm.

PPFD, on the other hand, is the total light density received by the plant throughout the growth process. PPFD measurements are in micromoles per square meter, per second, and it provides growers with the ability to get accurate measures for photosynthesis light intensity at their canopy levels. Another benefit of knowing about the PPFD is to avoid placing the lights too close to the canopies, thus preventing discoloration, stunted growth, burning, and bleaching.

Bestseller No. 1
AMTAST Quantum PAR Meter Quantum Sensor Advanced Quantum PAR Meter Light Intensity Measuring AMT312
  • This hand held PAR meter mainly used for agriculture, forestry and other research and production departments for PAR radiation measurement.
  • The Advanced Quantum PAR Meter provides measurement for any light source used in horticultural applications.
  • This Quantum PAR Meter is designed to measure PAR (Photo synthetically Active Radiation) flux in wavelengths ranging from 400 to 700 nanometer. MAXIMIZE CROP YIELDS.
  • Its characteristics are the spectral response simulation probe photosynthetic function effectively, digital show, portable compact, with good accuracy and stability, with recording of up to 99 readings.
  • In controlled environment agriculture (CEA), it is ideal for growers to measure light to avoid the risk of wasting energy or damaging their plants.
Bestseller No. 2
PHOTOBIO LGBQM2 Advanced Quantum Sensor PAR Meter (Micromoles), Measure Light Intensity
219 Reviews on Amazon
PHOTOBIO LGBQM2 Advanced Quantum Sensor PAR Meter (Micromoles), Measure Light Intensity
  • ACCURATE and COST EFFECTIVE: The Phantom PHOTOBIO Advanced Quantum PAR Meter provides measurement for any light source used in horticultural applications.
  • MEASURES BROAD SPECTRUM: The Advanced Quantum PAR meter is designed to measure PAR (Photosynthetically Active Radiation) flux in wavelengths ranging from 400 to 700nm.
  • MAXIMIZE CROP YIELDS: There is a positive proportional relationship between the number of photons absorbed in 400 to 700nm band and the rate of photosynthesis.
  • COMPACT and COMPLETE main unit, remote sensor, two connection cables (short-coiled & 12’ long-straight), AAA batteries and protective carrying case.
  • RELIABILITY: Phantom’s track record of robust reliability and performance in horticultural equipment
Bestseller No. 3
Quantum PAR Meter Full-Spectrum High Precision PPFD Tester for Photosynthetic Activity of Indoor and Outdoor Plants 400-700nm Light Lux Tester
  • ✅RELIABLE TESTER: The measurement range is between 0 and 5000 μmol/m²/sec. The cut-on wavelength is 400 nm and the cut-off wavelength is 700 nm with a tolerance of ±10 nm, which indicates that the meter is designed to measure the PAR within this defined waveband, providing accurate and reliable readings of the amount of light energy available for photosynthesis.
  • ✅RECORD FUNCTION: It has the capability to store up to 100 measured values. This allows the user to easily track and review previous readings, providing a record of the changes in PAR over time. Additionally, it has a real-time display feature that shows the last four recorded data, providing a quick and convenient way for the user to view recent measurements. This feature is particularly useful for monitoring and tracking changes in light energy levels in real-time, allowing for prompt and informed decisions to be made
  • ✅USAGE: A PAR meter is a valuable tool for growers, scientists, and researchers, providing accurate and reliable measurements of the amount of light energy available for photosynthesis, allowing for improved plant growth, increased energy efficiency, better crop management, and increased understanding of plant needs.
  • ✅TRIPOD SOCKET: It comes with a tripod socket to provide a convenient and practical way to securely attach the meter to a tripod (not included in the set), ensuring stability and accuracy during measurements, and providing greater flexibility in taking measurements
  • ✅ON THE GO TESTER: Portable, easy-to-use, flexible, and convenient tool for measuring PAR levels. It is a compact and lightweight design making it easy to carry the meter from one location to another, allowing for measurements to be taken in different parts of a greenhouse, growth chamber, or field. Ergonomic and user-friendly interface.
Bestseller No. 4
Par Meter Quantum Par Meter for led Grow Lights 400-700nm Spectrum Par Light Meter ppfd Meter with 100 Groups Data Logging, Calibration Function for Plants, Aquarium, etc.
  • ✅【High Precision】The measurement range of the par meter is up to 4000μmol/m²/sec, wavelength range is from 400nm to 700nm, providing accurate and reliable readings.
  • ✅【Data logging】This par meter is able to record up to 100 groups data, it's easy to review the previous readings, providing a quick and convenient way for the user to view recent measurements.
  • ✅【Flexible Sensor】This par light meter comes with 2 connecting cables, one is 4.9ft coiled cable, the other is 12ft straight cable, allow you to measure the different position quantum light easily
  • ✅【Multi-Functional】The sensor of Par Meter is designed with a 1/4'' tripod screw mount, Calibration, data record, RCFS functions
  • ✅【Wide Applications】It's portable and flexible quantum par meter for measuring PAR level in different applications, widely use for greenhouse, Aquarium and outside.
-$10.00 SALE OFFBestseller No. 5
PAR Meter up to 6000umol/(㎡s) DLI Calculator PPFD Recording
  • FH-100 can test the PPFD accurately. The main spectra of LED | CMH, HPS and SUNLIGHT are different,plants have different perception abilities for these light sources, and the meter have special design for this.
  • When testing PPFD in a closed tent, you can close the tent completely and get the most accurate PPFD by using our meter. While for other meters, you must open one side of the tent to do it, so the light will leak out.
  • You can recorded the PPFD data for different location by grids and calculate the average.
  • Can calculate the DLI if the PPFD is stable all the way.
  • We use Vsensor APP to instead of TUYA APP in 2023 now, more simpler and safer.

Where Should Be The Distance Between LED Grow Lights And Different Stages Of Growth?

Cannabis plants go through three main stages- seedling (cloning), vegetative, and flowering that all need different light intensities.

Distance Between LED Grow Lights And Different Stages Of Growth-2

Distance from Seedlings

The seedling stage is the most vulnerable phase, and it does not need as much light intensity as the other stages. If you have to use lights during the seedling stage, they should be high up above the plants to prevent the soil from drying up. Some growers make the mistake of intensifying the light to promote faster growth, but this is not the best way to go with seedlings. The best distance to maintain between LED grow lights and seedlings is 24 to 35 inches. Once the roots establish and sprouting begins, you can reduce the distance between the lights and the plants.

Distance between light and Clones

Cloning is one of the most popular practices among many cannabis growers. The process involves growing cannabis from cuttings or clippings of mature plants. The distance between LED grow lights and clones is different from that required for the seedlings.

Unlike seedlings, clones need intense light to start the growth process, and the distance from the light to the canopy should be between 14 and 36 inches depending on the plant maturity and wattage of the LED grow light.

The distance required for the Vegetative Stage

The vegetative state requires intense light. It is the phase that plants start maturing and making use of photosynthesis for faster growth. LED grow lights should be closer to the plant canopies during this stage to increase the light intensities.

The best distance requirement between the lights and plant canopy during the vegetative state should be between 12 and 24 inches. Even though the plants need high light intensity during this phase, you should monitor them closely to prevent adverse effects that too much or too little light intensity may cause.

The distance required for the Flowering Stage

The growth cycle’s final stage is the flowering phase when the plant goes through buds’ production and acceleration of stem growth. During the transition period between the vegetative and flowering phases, you should raise the height of the lights from the canopies.

Raising the light’s height should be gradual, and you should monitor the process closely to ensure that the distance does harm the plants in any way. Unlike the vegetative phase, light intensity during the flowering state should be lower. The required distance between the light and the plant canopy should be between 16 and 36 inches.

The plants also tend to grow in height during this stage. If you want to keep the height of the plants short, you do not have to increase the height between the canopies and the light. However, if you keep the lights too close to the canopies, you may end up with plant damage or wider sprawling growth.

Read next: How Many Watts Per Square Foot for Led Grow Lights

The Effects of Too Much Light On Cannabis Plants

Cannabis plants need enough light for faster vegetative growth, photosynthesis process, and development of healthy buds. Some of the reasons cannabis growers prefer LED grow lights to other traditional grow lights is because they are easier to monitor and do not produce too much heat.

Even though cannabis requires lots of light for healthy growth and high yields, too much distresses the plants. The same case happens if you do not provide the plants with enough light. The side effects to expect if the grow lights are too close to the plants are:-

  • Irregular or stunted growth
  • Sunburn
  • Plant defoliation
  • Plants withering or dying
  • Bleaching or upward-facing leaves
  • Yellowing of the leaves
  • Green stained veins

PS: Due to the effect  of covid 19, many products on amazon stil not unavailable, so I tried to find some other quality supplies, you can click on the image bellow for more information.

New Product: ( On 2021)



Check For More Information



Check For More Information



Check For More Information

Wrapping It Up

Every cannabis grower wants to have maximum yields from high-quality buds within the shortest time possible. Grow lights play a major role in determining the time it takes for the crops to mature. Light also improves the crops’ status, but only if you maintain the correct distances from the plant canopies.

Maintaining the required distance also provides you with the desired height and plant uniformity. Calculating the distance required using LED grow lights does not come easy for many cannabis growers. Still, we hope this article makes it easier for you to make correct distance calculations for your next cannabis growth cycle.

5/5 - (3 votes)

Bowden draws from over a decade of home growing experience as well as consulting for small-scale and hobbyist-level growers. He has written hundreds of articles, thought pieces, and tutorials about growing cannabis at home

Leave a Comment