How Does White Light Affect Plant Growth? (Updated 2021)

 LED grow lights are a great way to have plants indoors. They provide the perfect spectrum of light for your plants and can be used both during the day and at night. LEDs can be used as a sole source of light for your plants. On the other hand, they can also make great supplementation to sunlight coming through your windows. That’s because LEDs emit light in specific wavelengths (colors), and this is directly related to their electrical properties. The plants will also tend to grow much faster than they would otherwise because this type of lighting encourages healthy growth.

Although common grow lights emit blue and red light, these lamps come in many different color combinations. Because each color has different effects on the plant. So, what color light is useful in plant growth?

Why Do Plants Appear Green?

You might be surprised to find out that plants don’t absorb green light. So why do plants look green? Think about it this way: When you look in a mirror, that mirror reflects light back at your eyes. That explains how you can see your reflection on its surface. You see green when you look at a leaf because it is reflecting that light while absorbing others. The color most associated with plants is the color they are turning away.

What Colors Do Plants Absorb?

Photosynthesis works by absorbing light and using the energy from that light to make sugars the plant can use. The light plants can use for photosynthesis is called ​photosynthetically active radiation​, and it just happens to be the same spectrum of light that we can see. Plants absorb light by using pigments called ​chlorophylls​, which are really good at harnessing the energy from light as they absorb it.

Of those chlorophyll pigments, the primary one is called ​chlorophyll a​. It doesn’t absorb all wavelengths equally. In fact, it’s a little picky about what it picks up. Think about the colors of the rainbow (red, orange, yellow, green, blue, indigo and violet, in that order).

Chlorophyll a picks up some red and orange light while it reflects yellow, green and blue. Its favorite colors, though, are indigo and violet, as it absorbs those colors at nearly double the rate it picks up red and blue. There are other pigments in leaves as well, like ​chlorophyll b​, which absorbs some slightly different wavelengths, and ​beta-carotene​, which reflects red through green while absorbing a bunch of blue.

Does the Colour of light affect plant growth?

The color of light DOES affect plant growth, but the effect is more noticeable under low light intensity. Red & blue light are most effective for plant growth, while yellow & green have minimal effect. UV light can damage plants, causing leaves to burn. Growers often use supplemental light to optimize plant growth.

Best LED Grow Lights Recommend For You 

ECO Farm 480W LM301B Classic Quantum Board

Features:

The ECO Farm LED grow light is equipped with High Efficient Samsung LM301B LED series diodes and Dimmable MeanWell Driver, high efficiency and powerful output, enabling you to obtain higher yields. Only consumes 480w, which saves up to 50% energy than HPS or other SDM LED or Blurple light. Veg footprint: 5 x 5 ft, Bloom footprint: 4 x 4 ft. The real Sunlike full spectrum with white, blue, red and IR diodes (3000K, 5000K, 660nm and 730nm), infinite close to natural light, provide all types of indoor plants and all growth stages with full spectrum lighting and help plants grow better and healthier, bring higher yield in a shorter time. Tips: the IR LEDs look dim, but it works. This group dimming control function not need an extra control panel, very convenient to the extent the coverage for big indoor growing houses or large growing tents. No Fan&No Noise, the Fanless design bring you a quiet and better life; with high-quality aluminum heat sink board can quickly disperse heat, reducing light lost to aisles and walls, allowing your plants receive more energy; the additional waterproof function can protect the light intensity avoid the damage in a moist planting environment.

King Plus UL Series 4000 LED Quantum Board

Features:

KingLED developed the most efficient and safe Quantum Grow Light, using SAMSUNG chip, UL power supply (safer, longer use time), high-strength aluminum alloy heat plate (lower operating temperature and not easy to deformation), high-quality products bring the highest cost-effective. No fan No noise, the structure is more simple, lightweight, easy to install, cable special protective cover, waterproof LED pancel, far below the traditional LED lamp operating temperature, so that its service life is extended by 100%, high-quality products bring longer lifespan. Blue,White,Red and IR (660–665nm,3000K,5000K and IR 760nm), provide all the spectrum needed for plant growth, let your plants thrive, high-quality products bring higher yield. SAMSUNG chip, energy-saving technology representatives, compared with the traditional LED LIGHT, HPS, while providing efficient lighting, the actual power is only 323.9w, high-quality products bring lower electricity bill

Spider Farmer LED SF 4000 Quantum Board

Features:

SPIDER FARMER LED Grow Lights delivers powerful light output and uniform canopy penetration to resulting maximum higher yields. Upgraded SF4000 growing lights. The diodes arrangement gathered at the edge makes the PPFD more uniform, and the dimming knob be adjusted the light intensity at liberty. Multi-light Connection with unified dimming especially beneficial for large area of indoor growing and commercial planting. Excellent full spectrum- white, blue, red and IR. 3000K diodes providing more reddish light and the 5000K providing more blueish. The 660nm red and IR light is especially useful during bloom, speeding up flowering time and boosting yields. Turn your seeds into your own supply. And the light looks fairly natural, so it’s good for accurately monitoring plant health. No Fan Noise Free. High Safety performance MEAN WELL Driver, Fair Waterproofing.

Is white light good for plants?

The truth is that white light works great to grow plants. The sun provides white light, after all. Red and blue wavelengths are the most important for photosynthesis, but plants use all wavelengths of light. And white light provides all wavelengths.

How White Light Affects Plant Growth

You may have seen the studies that showed white light resulted in the fastest photosynthetic rate, followed by red and blue. While this does show that white light is great for plant growth, it is also a bit misleading.

These studies used only a single color of light, meaning they used either red or blue. When that is compared to white light, which contains all colors, it should be obvious that white light would perform best.

No one has ever said that plants want only red or only blue. It is the combination of the two that was said to be ideal. That combination should have been compared to white light.

That said, the idea that plants use only red and blue has been thoroughly debunked. Plants use all colors and that is exactly what white light provides. Because it provides all colors, and because it is the light that plants receive out in nature, white light is the best light for plants.

High pressure sodium and metal halide bulbs have been growing plants successfully for decades. They provide white light. None of the red and blue LEDs ever really outdid HPS for flowering.

Ceramic metal halide light has improved on HPS and MH to provide a fuller spectrum that is much closer to natural sunlight. And now, white LED diodes are also able to provide a full-spectrum light similar to CMH and to natural sunlight. These white LEDs have finally been able to outperform HPS light.

Conclusion

Many people choose to use LED Grow lights because they are energy-efficient, and this helps contribute towards healthy plant growth in various indoor environments like homes, greenhouses, patios, bedrooms, etc. LED fixtures to produce bright colours are usually the most effective ones for growing plants indoors. There are other ways that people use these lights to help their plants grow, but using them as supplements is one of the easiest and straightforward options.