Log In

Can any LED light be used as a plant grow light?

Not all LED lights are suitable for plant growth lights. Ordinary LED lights are mainly designed to meet human visual lighting needs. Their spectral distribution focuses on the visible light region, especially the blue, green, and red bands that the human eye is sensitive to, to provide a bright and comfortable lighting environment. However, plant growth has specific requirements for the spectrum, and different spectral bands have different effects on the physiological processes of plants. For example, red light is conducive to the elongation of plant stems and promotes flowering and fruiting; blue light is essential for the growth of plant leaves and the synthesis of chlorophyll. The specific analysis is as follows:

 

  1. Spectral composition is the key limitation

‌Plants rely on specific spectra‌

Plant photosynthesis mainly absorbs ‌red light (620-750nm)‌ to promote flowering and fruiting, and ‌blue light (430-460nm)‌ to support leaf growth and chlorophyll synthesis. The spectrum of ordinary LED lights is mainly white light, with a high proportion of blue and green light and insufficient red light content, which cannot accurately match plant needs.

‌The proportion of invalid light is too high‌

Ordinary LED lights contain a large amount of ‌green light (500-580nm)‌ that plants hardly absorb, and have low energy utilization; professional plant lights increase the proportion of red and blue light to more than 80% by eliminating invalid spectra.

 

  1. Differences in lighting efficiency and effect

‌Short-term availability but long-term inefficiency‌

Experiments have shown that ordinary LED lights can prevent plant wilting in the short term (better than a completely dark environment), but long-term use will lead to problems such as slow growth and reduced flowering. For example, the seedling period may barely last, but the flowering and fruiting period is prone to failure due to insufficient red light.

‌Professional lamps have significant advantages‌

LED plant lights can shorten the growth cycle by about 7 days and increase the yield several times by customizing the spectrum (such as a red-blue ratio of 3:1 or full spectrum), adjusting the light intensity (1000-3000μmol/m²s) and the photoperiod. For example, factory planting has achieved year-round production.

 

  1. Alternative solutions

‌Temporary emergency‌: If only short-term supplementary light is needed (such as rainy days), ordinary LED lights can be used temporarily, but they need to be close to the plants (20-30cm) and the exposure time should be extended.

‌Economic choice‌: Full-spectrum LED lights (color temperature 5000K-6500K) are closer to natural light than ordinary lights and are suitable for many varieties of plants.

‌Must-have for professional scenes‌: When large-scale planting or flowering period/yield requirements are required, special plant lights with adjustable spectrum must be used.

 

Conclusion‌

Although ordinary LED lights can provide a certain amount of light, the spectral composition is difficult to meet the optimal needs of plant growth. Using ordinary LED lights instead of plant growth lights may lead to problems such as slow plant growth, poor development, delayed flowering and fruiting, or poor quality. Therefore, in pursuit of healthy growth or high yield, it is necessary to choose special LED plant lights with a high proportion of red and blue spectrum and adjustable light intensity.