UV Light for Plants: Is It Necessary?

What Is UV Light

UV light, or ultraviolet light, is a form of electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays. It is named "ultraviolet" because it starts from the wavelengths just beyond the violet end of the visible light spectrum. The wavelengths of UV light range approximately between 10 and 400 nanometers (nm).

3 Types of UV Light

UV light can be categorized into three main types based on wavelength:

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UVA (Long-wave Ultraviolet A):

Wavelength: 320-400 nm

UVA makes up the majority of the UV light reaching the Earth's surface. It can penetrate deeper layers of the skin and is primarily responsible for skin aging and the formation of skin cancers. UVA is also used in black lights and tanning beds.

UVB (Medium-wave Ultraviolet B):

Wavelength: 280-320 nm

UVB is partially absorbed by the Earth’s atmosphere but is more energetic than UVA. It is responsible for sunburn, skin aging, and the development of skin cancers. It also plays a key role in the production of vitamin D in the skin.

UVC (Short-wave Ultraviolet C)

Wavelength: 200-280 nm

UVC is the most dangerous type of UV light, but it is almost entirely absorbed by the Earth's atmosphere and does not reach the surface. Normally, UVC is not applied to plant growth. 

Should You Use UV Light for Plants

To your surprise, plants do not necessarily need UV lights to grow - what they need most during the plant life cycle is red and blue light. However, gardeners who opt for UV lights for plants are more likely to have robust stems, healthy foliage, and quality yields. To make it more clear, here’s a breakdown of what benefits UVA and UVB light bring. After reading it through, you can decide whether to use a UV plant light or not. 

Benefits of UVA Light

• Morphological Development: Exposure to UVA light influences the morphology of plants, resulting in compact and sturdy growth, essential for crops and ornamental plants.
• Flavor and Color Enhancement: UVA light enhances the production of pigments, flavonoids, and antioxidants, improving the color, flavor, and nutritional value of plants.
• Pest Control: UVA serves as a natural deterrent to certain pests, reducing the dependency on chemical pesticides.
• Faster Photosynthesis: Studies have shown that exposure to UVA light can speed up the process of photosynthesis by around 12%, leading to increased growth, leaf size, and dry weight.

Benefits of UVB Light

• Stress Induction: Moderate exposure to UVB induces mild stress, stimulating the plant’s defense mechanisms and production of protective compounds.
• Increased Resilience: The induced stress enhances resilience against diseases, adverse weather conditions, and pests.
• Improved Flavor and Aroma: Stress-induced production of secondary metabolites enhances flavor and aroma in culinary herbs and crops.

Best UV Lights for Plants Recommendation

Frankly speaking, though there are UVB grow lights on the market, it’s not necessary to buy an exclusive UV light for your plants, as plants require a more comprehensive light spectrum to grow. So how can you benefit from the UV wavelength without spending big money? Spider Farmer 40W UV & IR LED Grow Light Bar comes as the best solution. 

This light bar is designed to provide supplemental lighting to indoor plants with a targeted spectrum, including UV (365-420nm) and IR (730-745nm) wavelengths. With a power output of 40W, the light bar is designed to be energy-efficient, providing optimal light intensity with minimal energy consumption. You can freely install this light bar to existing indoor grow lights to offer optimal lighting conditions for indoor gardening.