Supplemental Lighting | Cultiuana

What is supplemental lighting?

Supplemental lighting is artificial lighting used indoors to give your crop extra high-intensive lighting and a more optimal light spectrum for their growth. The supplement lights can be used in the greenhouse. They are usually used during winter or when growers have cloudy weather.

Growers can apply supplemental artificial lighting to increase greenhouse yields and ensure stable year-round production. When used indoor grow room, supplement lights provide the lighting to the areas your primary lighting can't reach, such as the bottom and shaded space or the outer edges of your primary light's footprint. And as we mentioned above, supplement lights also provide a light spectrum that your existing lamp lacks, such as a low amount of red in MH bulbs.

Supplement Light Type

Supplement lighting has three types.

1. One-color supplement light

These lights are often shaped like bars and can be hung above, below, or on the sides of plants. We also call it side lighting. Each bar gives off one specific color of light that helps with particular growth stages. You can find them in blue, red, UV, and IR.

2. Multi-band light panels

There are more than two colors in each light so the light will be wider than the lighting bars. The LEDs on the panel consist of red, blue, or sometimes UV or far red LEDs.

3. Full spectrum lights

As the name suggests, the full spectrum supplementary lights deliver the complete wavelength plants need during their entire growth stage.

Benefits of Using Supplemental Lighting

There are several good reasons to use supplement LED lights in grow room.

1. Improve the uniformity of light intensity

No matter how intensive primary lights you use, they aren't powerful enough to get far into your plant, especially in some small spaces. The light from above isn't able to bounce off the walls effectively enough to reach the lower parts of the plant. In this situation, you need supplement grow lights. These lights help cover the weaker spots in your plants' canopies. Moreover, primary lights lose intensity the farther their light travels, causing plants outside their range to lack light. This uneven light coverage can result in smaller, less satisfying yields.

2. Give your plant the specific light type it needs at each stage

These lights let you set the perfect mix of colors for your specific plant type at each point in its growth.

When plants are almost ready to flower, putting in a few IR LED lights can make them bloom earlier and bigger. UV lights can increase certain compounds, colors, resins, and oil production. When plants get UV light, they create these substances to protect themselves, just like you use sunscreen to avoid sunburn.

Another example is increasing far-red light (750nm-780nm) can promote stem growth and flowering – which growers want. On the other hand, a little blue light can stop stems from growing unevenly and leaves from shrinking.

3. Speed Up Your Harvest Cycle

For example, if you have a greenhouse and rely only on sunlight for growing, you're limited by the changing seasons. Using supplemental led lights, you can help your plants grow from seeds to harvest faster than sunlight alone. This would allow you to have more growing cycles each year. Even if you live in a place with less sunlight or it's the middle of winter, the lights give you the right intensity and range of light to create any season inside your greenhouse.

4. Work simultaneously with the primary light

Many LED supplement lights can be connected to your main light and run on the timer. The built-in sunrise and sunset feature helps your plant know when to transit from one process to another.

5. Savings on operating costs

Most areas of the U.S. offer a rebate for greenhouses that use LED lights, making the lighting much more affordable than before and providing benefits in the long term.

6. Long-lasting and perfect quality

No matter how expansive your operation is, your plants keep you busy. So, it's a significant benefit to install lights without considering changing them for 10-15 years. With extra LED grow lights, the best quality ones can last more than 50,000 hours. This means you won't have to worry about them while growing plants each year.

How to Install Supplemental Lights?

• Install Above the Indoor Plants. Put them above plants to strengthen the primary light and have more wavelengths.

• Place Below the Indoor Plants. Put them below plants so light reaches the shadowed parts, making growth more even from top to bottom.

• Set up on the side of the grow tent. Put them on the sides of plants to make the primary light cover a larger area and strengthen at the outer edges, as the light gets weaker when it spreads out.

• Install within the Greenhouse 

  Supplementary lights used in greenhouse enable growers to maintain optimal light levels throughout the year, even in bad weather or in locations with limited sunlight.

How to Choose Supplemental Lighting?

1. Choose the correct wattage

Your main light is already strong, so your extra lights don't need to be too bright. Choosing ones between 50-100 watts is enough. These 50-100 watt lights typically create 80-140 PPFD.

2. Choose the right band

Your crop needs a specific color during different growth stages. Using LED grow lights, you can select the precise spectrum that your plant requires to supplement primary lighting or another lighting, such as HPS. 

Blue light is important for growth to help plants create strong stems, thicker growth, and established roots – all of which occur in the early vegetative growth stages. Growth keeps going with more red light, which results in longer stems, bigger leaves, and more flowers or fruits. Small amounts of UV light can help improve color, taste, and smell. Far-red light at 730nm can be used at the end of a light cycle to encourage flowering.

3. Determine how much of the growing area you want to supplement

For example, if you want to increase PPFD 280umol in your 6x6 grow space, and each 100-watt LED extra light gives 140 PPFD, you'll need two of these lights to add more light.


In short, supplemental lighting can be used when you need to make light levels higher for better results or change the light spectrum based on the growth stage.