Best Lighting For Growing Microgreens


Best Lighting For Growing Microgreens

In microgreen farming, light is one of the key requirements. Microgreens can look pale and frail without adequate light. This is why we will be looking at the best lighting for growing microgreens. Normally you can grow your micro-greens using sunlight or artificial lighting. 

The good news is that they do well in a number of light sources. So it’s easy to get yourself started and add on as your needs and funds increase. A couple of trays for the home grower in a sunny window through several vertical rack systems with dedicated growing lights for commercial production. 

The issue of which lights can be used is complex and depends on many factors. 

  • Do you grow for home use or for business? 
  • What is the number of trays you grow? 
  • Do you have access to sunlight, IE. sunroom or greenhouse?
  • Are you planning to grow all year? 
  • Are you looking for reliable harvesting times, or more flexible harvested yime? 
  • How much money could you spend on your lighting system?

There are different lighting options that can be used for growing basil microgreens. 

The best lighting for growing microgreens, however, is the Fluorescent Tube/Compact Fluorescent Light (CFLs)

Other lighting options include:

  • Sunlight
  • LED Bulb Shop Lights
  • LED Strip Grow Lights (T5)
  • LED Panel Lights
  • Incandescent light bulb/Halogen lamp/Tungsten
  • Light-emitting Diode (LED)

Best Lighting For Growing Microgreens

Sunlight

Naturally, this is the cheapest and most complete usable light source. Any sunny window sill or small greenhouse can be used by the home grower to grow microgreens. Greenhouses or high tunnels with tables may be used for the production of microgreens in larger operations, where limited space does not pose a challenge.

Pros

  • Free
  • Readily available
  • No wear and timers required
  • It offers a full spectrum of light on a clear day (within the range of 6500k).

Cons

  • Inconsistent with weather and seasons
  • The heat it produces can affect microgreen growth,
  • It does not operate well with vertical rack systems and needs additional lighting during winter months.

Shop LED Bulb

These can be bought for around $20 apiece in most big box shops. They’re a standard 4′ long. These are an excellent test light when you are prepared to test indoor growth or need to use a vertical rack to increase ability within a small footprint.

Pros

  • Cheap
  • Easy to find
  • Appropriate light spectrum for microgreen growth (2200k-4000k)
  • Minimal heat generation
  • 3-4 lights can be daisy-chained
  • Works with 120V domestic electrical outlets.

 Cons

  • Bulbs are often unprotected against water and dust, making them vulnerable to damage
  • Brands are highly variable in quality.
  • They are typically mounted only horizontally

LED Strip Grow Lights (T5)

Dedicated light strips are typically sold as shop lights in the same standard 4′ range.  They come with a full spectrum, over 5000k strip lights, with prices ranging from $75 to $650. The majority of these offer a 4’x2′ growing area. They can come with or without a reflector (which gives the classical shop light shape and aids in redirecting light, thereby improving efficiency).

Pros

  • Moderately expensive
  • Full light spectrum 4500k and above allows for longer growing periods
  • Produces minimal heat
  • The good ones offer lighting surfaces that are protected against dust and water. 

Cons

  • Moderately expensive(pro or con depending on your situation)
  • Quality efficiency and longevity can vary greatly between brands.

LED Panel Lights

These are the best growing lights for indoor use. They are usually used to grow plants on a bigger commercial scale that have to reach full size or produce flowers indoors. For growing microgreens, the high light intensity can be considered overkill. They can be extremely expensive for the small growing area ranging from $99 to $1,000. 

 Growing area covered is typically 3’x3’ for smaller panels up through 8’x8’.

Pros

  • Come in a variety of sizes
  • Intense full spectrum light capabilities Variable sizes for customized growing spaces
  • Highly efficient watt to lumen ratio.

Cons

  • Expensive
  • Thick profile limits their ability to work in vertical rack systems
  • Generally require separate ballasts for electricity
  • Must be purchased from specialty suppliers online or in hydro stores if they are available in your area.

Incandescent Light Bulb/Halogen Lamp/Tungsten

The Incandescent light bulb is the common bulb with a thin filament inside. The filament is electrically heated and lit up. 

Incandescent light has a wider range of light, with the majority of its emissions being infrared and ultraviolet. And so it’s said to be less efficient because most of the energy is used for heat instead of light. 

You might have to bring the light closer to microgreens for greater light intensity or increase the hours of light exposure. But then, the microgreen may burn under the heat.

Pros

  • Compared to both the LED and CFL,
  • it’s not a very cost-effective option For the price, incandescent light is cheaper. 

Cons

  • It actually costs you more electricity to operate in a long run
  • Most incandescent light bulbs do not last longer than 3 months (1,200 – 2,000 hours).

Light-emitting Diode (LED)

LED light is a newer technology compared to fluorescent light, with better intensity, lower watts, higher efficiency, lower cost, very low warmth, longer service life, and without mercury. The original price is higher, but in the long term it can pay off.

However, LED is sensitive to heat. At higher temperatures, the life span may drop dramatically. Therefore, please check your surrounding temperatures, if you intend to use them for micro-greens. 

Contrary to others, LED light is designed to produce a specific range of wavelengths and LED light has a relatively shorter and narrower wavelength In microgreen farming, LED light is less used because microgreens usually need a wider colour spectrum (just like sunlight) to develop better. 

That said, each range of wavelength will serve its own purposes: 

Far-red – Improve the yield (blooming and fruiting). 

Red & Blue – To promote fast growth of the plant. 

Green – Enhance the chlorophyll production. 

Yellow – Observed a slower growth.

Blue & Violet – Enhance colour, taste, and aroma.

Ultraviolet – Slow down the growth and damaging the plant.

Fluorescent tube/Compact Fluorescent Light (CFLs)

Fluorescent light uses electricity to excite the vapour of mercury to create ultraviolet, short wave light. Then the light photons collide on the phosphorus layer to create visible light.

For many microgreen cultivators, the fluorescent tube is a popular alternative. Fluorescent lights are much more effective, less expensive, less heat generated, with more light intensity, and more robust (9,000-20,000 hours) when compared to incandescent lights.

The best choice for microgreens is the fluorescent T8s and 4-pin CFL. In comparison to T12 and 2-pin ballast CFLs, T8s and 4-pin CFLs use a newer ballast model, and as a result, do not make any buzzing noise.

Pros

  • Fluorescent light is substantially better than other growing lamps
  • Lower cost
  • Lower heat output
  • Better light intensity
  • Longer service life.

Cons

They contain a constant deposit of mercury, and if they break up, they can contaminate your growing area.

Frequently-Asked Questions

How Far Should My Light Be From Microgreens?

This depends on the light source that is used, as the heat can burn microgreens if placed too close. Most LED strips don’t produce enough heat to cause problems and do well in placed 6-12 cm from the surface of the microgreen.  

The farther the greens are from the source of light, the more they “stretch” and become leggy. 

Panel light is higher in intensity and can be placed farther away with no excessive loss of light.

How Many Hours Of Light Do Microgreens Need?

Much like us human beings, microgreens like to rest from the light. In fact, the foliage can curl up if it stays too long under high-intensity light.  It is also dependent on the type of microgreen.   

There are as many views about this as growers. 

Certain microgreens would need more light, namely, the sunflower. 

The rule is that plants need at least 6 hours of light per day to grow.     

If you’re using sunlight as your primary source of light, you are of course limited to the time available to you, most micro-greens will need to be exposed to shaded sunlight at least 6-10 hours a day. 

You can get the most out of your hours by being mindful of the shade patterns and light direction during the setup of the process. 

You should experiment at home on what works best for you. Some growers keep their lights 24 hours a day to accelerate growth. Others use a shift of “12 hours off, 12 hours on”.  

Here is a good medium between additional light hours to allow growth and allowing the plants to “rest.” 

For t8 fluorescent indoor light, as an instance, 12-18 hours would work. 

In other words, fluorescent and incandescent light promote faster growth and healthier microgreens are produced by an LED light. 

A note on light-spectrum -most light will be labelled between 2000K and 6500K.   

The bottom end of this scale, colour temperatures between 2000 and 3000 K, is referred to as the “warm white” and range from orange to yellow-white in appearance.

The colour temperatures from 3100K to 4500K are known as “cool white,” with a neutral white light emitting from this line.

Above 4500K, a blue-white light is provided to imitate daylight. 

Due to the short time that most microgreens are cultivated, the light spectrum has less importance than the plant that grows longer or into a flowering stage.

 When growing microgreens, herbs or other plants that would stay longer than 20 days, it is advisable to use lights that produce a colour temperature above 4500k.

Can Just Any LED Light be Used as a Growing Light?

First, let me explain the different light data and what microgreens are looking for. 

Microgreens, like other plants, need light for photosynthesis. You will otherwise get yellow microgreens (also fantastic, not only for their results but are also sweeter than those with chlorophyll). 

The tubular diameter of the light tube is  T5(0.6″) or T8 (1″) or T12(1.5″) tube. The most widely used types today are T8 fluorescent lamps. The length of the lamp is 48 inches and its diameter is 1 inch. T8 and T12 lamps are also available in other lengths like 8-ft tubes, but the most common type remains 4-ft length. 

Lumens are a measure of how bright a light appears to the human eye and not how well plants grow from the LED light. Total wattage can measure light strength or intensity. The higher the wattage, the greater the intensity of the light.

Kelvins – Color Temperature 

Most fluorescent tube lighting has a colour temperature correlated (CCT) from 4000 K to 6500 K, as it is considered better suited for retail and office environments respectively. Likewise, LED tube lights in a variety of colour temperatures are also available. 

As the daylight is 6500 K, and we want it to be as close as possible, it should have a colour temperature of 6500K. 

Nm – waves, which plants require from 400 – 700nm in the visible region.  

Photosynthetic photon flux (PPF) designates the intensity of visible spectral radiation, which plants use in the photosynthesis process.

Detailed wavelengths of interest for growers using LEDs, within the 400-700 nm range, applicable to plants growth, are:

Nm rangeDescription 
439Blue – the absorption peak of chlorophyll A.
450-460The royal blue colour that is absorbed by one of the peaks in beta-carotene. It is a readily available LED wavelength commonly used to excite the remote-phosphor in white LED lamps
469Blue – the absorption peak of chlorophyll B. To promote quick growth of the plant.
430-470This blue range is important for the absorption of chlorophyll a and b, which is vital for vegetative growth.
480-485Blue colour – second absorption peak of beta-carotene.
525Green light, is a phototropic activator that researchers are still trying to find the chromophore of. Green light isn’t necessary for photosynthesis, but it is apparent that plants are gaining direction and environmental signals from it, and that it affects internodal spacing. It is also the wavelength of GaN or InGaN green LEDs commonly used in RGB and tunable applications.
590Yellow colour – key for carotenoid absorption. Carotenoids are starch-storing, structural and nutritional compounds.  is additionally the phycoerythrin absorption wavelength. Phycoerythrin are red protein-pigment complex from the light-harvesting phycobiliprotein family, found in red algae and cryptophytes, and is an accessory pigment to the main chlorophyll pigments responsible for photosynthesis.
625Orange colour – phycocyanin absorption peak. It is an accessory pigment to chlorophyll. Phycocyanin is a pigment-protein complex from the light-harvesting phycobiliprotein family, along with allophycocyanin and phycoerythrin. 
642-645Red colour – peak absorption point of chlorophyll b.
660Often called the super-red LED wavelength and is important for flowering.
666-667Peak red absorption point for chlorophyll A.
730It is important for phytochrome recycling. it’s often referred to as far-red. It is necessary for all types of morphogenic processes (shape forming). Improve yield (flowers and fruits). A few minutes of 730 nm light treatment after the full light cycle is over will revert the phytochrome chromophore from activated to inactive. This resets chemistry for a second light-on cycle and is useful in shortening the photoperiod’s classical dark side. For plants, this colour is essential but not included in the PPF because it is out of the PPF range of 400 to 700 nm. 

Conclusion

In conclusion, I think it would be good to experiment with different light cycles to see what works best for you. Therefore, we have written down the various available lighting and its pros and cons, which allows you to decide which one would be preferable and best suited for your grow area. 

After much consideration as to its advantages and disadvantages compared to other lighting options, you can then choose to go with what you have figured to be the best.

So, which lights would you go for?

Let us know if you have questions or feedback. You could also comment below what lighting system you have tried and which worked best for you?


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