LEDs are producing revolutionary advancements in many areas of technology and life, but none more so important than in horticulture. The complexity and knowledge required are growing daily, with different plants requiring different spectral illumination and control.
Ultraviolet light is extremely important for plant growth. In safe doses, ultraviolet light helps plants and crops produce essential plant oils which not only enhance the flavour and smell of fruit but also helps the plants protect themselves from excessive ultraviolet exposure; acting as their own natural sunblock.
This natural protection ensures that the internal processes of the plant are protected and ensures optimal growing conditions. Plants, in this respect, are very clever in that they will only absorb the correct level of ultraviolet needed for this self-protecting process to kick in and no more.
Ultraviolet is outside the photosynthetically active waveband (PAR – The total energy that a plant needs, 400 – 700nm), but it is biologically active and regulates plant growth. Some common positive effects of ultraviolet on crops include: –
- Inhibition of extension growth (shorter stems and smaller leaves)
- Increase in leaf thickness and waxiness (thicker cuticles)
- Greater leaf colouration (especially for plants with purplish leaves such as red-leaf lettuce, purple millet and purple fountain grass).
Research has also shown that plants which are subjected to ultraviolet radiation tend to have fewer pests feeding on them, show increases in pollination and provide an overall increase in yield.
Do I Need an LED Grow Light With UV?
Not necessarily, because as you can see, UV is only beneficial under the right circumstances. That’s why professional growers will use separate UV light bars to accurately control their lighting and get the real benefits of UV.
Many of the LED grow lights on the market today are equipped with only a smallamount of UV light, which helps to mimic sunlight. These lights will not cause any harm to the plants, nor will they have the benefit of UV and IR.
Even with a sufficient amount of UV, the UV lights on LED grow lights are not controllable. That means that you can’t have precise control over how much UV to use.
In the end, LED grow lights without UV LED chips do not make them inferior; rather, they offer the application scenarios for precise control of UV.
If you’re really interested in the benefits of UV, you’re better off getting supplemental UV light bars to add to your grow room. A full-spectrum LED together with supplemental UV bars will contribute a lot to your grow.