Horticulture lighting is the method for promoting plant growth by artificial lighting fixtures when natural light is lacking.
Professional horticulture lighting is not just about supplying sufficient light for plant growth through the enhancement of photosynthesis, but also about helping plants to produce a more beautiful flower, better shape of leaves and more fruit as well as reduce or lengthen a particular growing period.
For professional horticulture lighting, the right customized recipes are essential for optimization of plant growing on purpose. The particular needs of different plants in each growing stage and each part of plant organs determine which lighting recipe is better for optimizing growth.
Growth
Apart from the variables including temperature, humidity, water, oxygen, carbon and nutrients, special characteristics of lighting also play a major part in controlling plant growth. The light intensity, spectrum and duration impact plants' morphology, growth, fruiting and flowering.
Photosynthesis
Plants can transform light energy into chemical energy by photosynthesis. Plants need to absorb special light spectra emitting in order to generate necessary elements, such as chlorophyll, anthocyanin, carotenoid and phytochromes, within it's organs for growing. A professional horticulture lighting recipe should optimize the spectrum of light source to satisfy the plants needs for photosynthesis in order to maximize the growth rate and limit the electrical energy consumption at the same time.
PAR: Photosynthetically Active Radiation
Photosynthetically active radiation, also called PAR, represents the spectral range of solar radiation from 400nm to 700nm. It specifies the light the plant needs to support photosynthesis. In this range, plants' photosynthetic organisms are able to absorb light in the process of photosynthesis.
PPF: Photosynthetic Photon Flux
Photosynthetic photon flux (PPF) is a measurement that determines the overall amount of photosynthetic active radiation (PAR) a light emits. It values all photons from 400nm to 700nm based on the plant's photosynthetic response.
PPFD: Photosynthetic Photon Flux Density
Photosynthetic photon flux density (PPFD) is another measurement that offers the same information as PPF. It also stands for the photons in the spectral range of 400nm to 700nm. While the distinction between them is that PPF measures the number of photons given off from a source of light. On the other hand, PPFD refers to how many photons drop on a surface area in square meters.