We often recommend placing plants that are going to be kept at home in a room with plenty of light; that is, in which there are windows through which sunlight easily enters. And it is that all of them need light to carry out photosynthesis and, therefore, to be able to produce their food and grow. But, Is it possible to have healthy plants with artificial light?
The short answer is yes, you can.. Now it is important to choose the right artificial light for the plants, because not all of them will work. In fact, the light from the bulbs that we usually have in a house is not the most adequate to guarantee good growth. To do this, it will be necessary to obtain specific lamps or bulbs.
What light do plants need to grow?
Plants began their evolution about 400 million years ago, in the oceans. At that time there were only algae, in addition to microorganisms such as bacteria. But over time, some would start to rise to the surface, as happened with Cooksonia, which carried out photosynthesis through its stems because the leaves had not yet appeared. Later, somewhat more complex plants would grow, such as mosses, ferns or cycads. And about 150 million years ago the first flowering plants appeared.
Why am I saying all this? Because plants depend on sunlight for everything: breathe, photosynthesize, grow, flourish, etc. Through their photosynthetic parts, ie those that contain chlorophyll, which is the pigment that gives them their green color, they transform sunlight into carbohydrates. But to better understand this, it is important to know more about solar radiation.
Although it may seem to us that it is more or less always the same, the human eye and plants “see” the world in a different way. And it is that the Sun, although it emits ultraviolet, visible and infrared radiation, people only see the visible, that is, when the wavelength is between 380 and 780 nm. Moreover, we are able to see three colors: blue, red and green, and their many combinations.
Plants, on the other hand, although they are sensitive to wavelengths between 400 and 700 nm, only absorb red and blue light, and reflect green, which is why we see them in this color. But also, that’s one of the reasons we can’t use traditional lights for them, because they’re made for us humans to see, not plants.
Why are plants green?
What effect do different types of radiation have on plants?
Depending on the radiation received by the plants, they will react in one way or another. For example:
- Growth: depend on infrared radiation and blue light.
- seed germination: blue light and to a lesser extent ultraviolet light are those that stimulate this process.
- Flowering and fruiting: they are aided by red or far-red light to flower and fruit.
- Shade plant growth: Under conditions where the ratio of red and far-red light is high, plants that do not receive direct sunlight can grow.
Can artificial light help plants?
As we anticipated at the beginning of this article, artificial light can indeed be helpful to plants. Now well, Everything will depend on the luminous flux of said lamp., which is measured in candelas or cd, illuminance or lux, or luminance (cd/m2). And it is that not all have the same luminous intensity.
Besides, you should know that it is also interesting to know how many photons will be provided. These are measured in micromoles of photons (mmol), which is a measure of flux or density. The latter is a measurement calculated taking into account the square meter exposed to light and the seconds it takes to receive it. Thus, the further away it is, the fewer micromoles of photons the plant will receive.
Nowadays, the artificial lighting of crops has been so modernized that suitable lighting systems can be found to stimulate, for example, seed germination, growth or flowering.
What is the best artificial light for plants?
Considering what we have said so far, choosing artificial light for plants will very much depend on what we are trying to achieve. For example*:
- Seed germination and seedling growth: if grown in areas with little sunlight, you should get lamps that emit blue (35%), red (25%), far-red (25%) and white (4000K, CRI70, 15%) light . But if there is natural light, blue (75%) and red (25%) light will suffice.
- Plant growth and development: If there is no sunlight, white (4000K, CRI70, 80%) and red (20%) light will be supplied. On the other hand, if there is, red light (90%) and blue light (5-10%) will be provided.
- flower production: to make it flower, if it is grown only with artificial light, it will be given white light (4000K, CRI70, 60%), red (20%) and far red (20%). On the contrary, if it receives natural light, the red light (60%) and the far red light (20%) will be reinforced; it may also need to be given blue light (20%) in low light conditions.
- Fruiting: If there is no sunlight, white (4000K, CRI70, 60%), red (30%) and far-red (10%) light will be used. On the other hand, if natural light enters the room, white light (4000K, CRI70 20%), red (70%) and far red (10%) will suffice.
*Note: This information was obtained from the SECOM portal.
You can get artificial light lamps here: