Light:
Through photosynthesis in the leaves, plants are able to build up glucose from water and carbon dioxide with the help of light radiation. Light is therefore the basis of strong and healthy plant growth. Together with the unique process of photosynthesis, it is also the prerequisite for life on earth.
Wavelength:
Sunlight consists of different wavelengths and plants use the visible part from 380 to 760 nanometers (nm). The blue-violet (443 nm) and red-orange (662 nm) light radiation exhibits the greatest photosynthetic activity.
Intensity:
In addition to the spectral composition of the light, the intensity (brightness) is also decisive for intensive photosynthesis. Light intensity is measured in lux (lx) and plants require between 10,000 and 40,000 lux for full photosynthesis.
Artificial light:
Plant lamps must cover the required color spectrum so that the plant can nourish itself sufficiently. Normal lamps for room lighting are unsuitable here. Special plant lamps, on the other hand, provide sufficient photosynthetically active radiation as they also cover the blue and red color spectrum.
Color spectrum:
Full spectrum lights provide all the wavelengths required for plant growth. They shine white and are also suitable for plant nutrition without additional lighting or natural light. Lights with only blue and red spectrum, on the other hand, can only be used as supplementary lighting and the light appears violet.
Light quality:
The quality of artificial plant light is indicated by the PPFD value (Photosynthetically Active Photon Flux Density). This value describes the amount of PAR (photosynthetically active radiation) that is actually available to the plant. The PPFD value is given in the unit µmol/(s·m²) and should be between 100 and 400, depending on use. For overwintering, 100 µmol/(s·m²) is often sufficient, although 400 µmol/(s·m²) may well be necessary in dark locations without natural light.
Use:
Plant light is suitable as supplementary lighting for overwintering tropical plants in the dark winter months. In summer, plant lights are used as support if there is too little natural light at the location or if growth is generally to be increased.