"Sun" for seedlings: how to choose the right phytolamp to get "strong"

How to calculate the illumination, find the correct spectral ratio and optimal distance to the air

Now, at the end of winter, almost every house has a pink light from phytolamps. In February, many gardeners began growing seedlings, and the short daylight hours make them look for options with backlit. You cannot grow strong seedlings without a phytolamp, but not all additional lighting will give the desired result. Let's consider which phytolamps for plants are suitable only for greenhouses, which ones can be used for seedlings, how to choose them correctly and how to use them as efficiently as possible.

How to properly supplement seedlings

When choosing a phytolamp for seedlings, the easiest way is to decide on its shape. Everything is simple here. If the pots with seedlings are in a row on a shelf of a special rack, or on a windowsill, or on another narrow and long surface (and seedlings are usually grown this way), then a linear type phytolamp is needed.

Sometimes the rows of seedlings are supplemented with two base lamps (or several).

It is more difficult to decide on the choice of the light source. The meaning of supplementary lighting is that artificial lighting lamps should be installed before daylight or after At the end of it, they replaced the plants with sunlight, which consists of waves of different colors and different lengths. For the growth and development of plants, the most important red and blue spectrum colorstherefore, not all lamps are suitable for growing plants.

ArmadRS

Amateur vegetable grower, FORUMHOUSE participant

Pink phyto is simply energy efficient as there is no extra spectrum. For plants, 100 watts of pink is comparable to 200 watts of white, but for you it is half the price.

Incandescent lamps are the worst choice for illuminating seedlings and for plants in general. The emission spectrum of incandescent lamps is limited mainly to the yellow and green spectrum; there is no blue in it. The second problem is that much of the electricity in these lamps is converted to heat. We have to move them away from the plants as far as possible, from this the already low efficiency of additional illumination decreases even more. Plants that have grown under a conventional incandescent lamp are easy to recognize: they are drawn towards the light and are always overly elongated.

With fluorescent lamps, the story is reversed, their spectrum is dominated by blue, but they emit little light in red and orange. areas, but red seedlings are still needed (and indoor plants are simply necessary, especially tropical exotics like lemons and coffee).

Sometimes in greenhouses they combine "lumines" of cold light and incandescent lamps that heat the air.

LED phytolamps

In recent years, the popularity of phytolamps that use LEDs has been growing. For a long time they were considered "good but expensive", but a few years ago, LEDs fell dramatically. The spectrum of such phytolamps contains both blue and red, they are called bicolor. A spectrogram is usually placed on the package, which shows the wavelength in both the blue spectrum and the red. The optimal wavelength for seedlings is:

• in the blue spectrum - 440-450 nm,
• in the red spectrum - 650-660 nm.

At FORUMHOUSE, the issue of the spectral ratio for supplementary lighting of seedlings and for lighting winter gardens has been discussed for several years. It seems that now the point has been set in this question, and the optimal picture looks like this:

The meaning of spectrum colors for plants

Although blue and red are the main colors in the spectrum for normal plant growth and development, other colors in the range from UV-C (370-410 nm) to NIR-A (700-780 nm) are important in their own way. To successfully solve the problems of growing seedlings and indoor plants using phytolamps, you need to know how different parts of the spectrum affect them.

• UV-C (370-410 nm) helps in the production of hormones that the plant needs to live; promotes the development of green mass and root system.
• Blue (410-480 nm) - in this color the plant develops a root system, acquires resistance to frost, produces carotenoids, and builds up green mass;
• Blue and green (480-565 nm) are part of the spectrum visible to the human eye. It is necessary for the lower tiers of leaves and the stem of the plant. Pale leaves of the lower tier signal that there is no chlorophyll in them, and, therefore, there are no blue and green in the spectrum of the light source;
• Yellow and orange (565-625 nm) - in this part of the spectrum, the process of photosynthesis is accelerated in plants, leaves are strengthened, plants produce beta-carotene;
• Red and IR-A (625-780 nm) are necessary for fruit ripening, but too much with these colors in the source spectrum lighting can become fatal for the plant and lead to overheating, falling off of inflorescences and the same stretching. For the most part, red and IR are vital for fruit ripening.

The main advantage of LED sources is that you can make up any spectrum from them, set any modes and control them. Here it is important not to make a mistake with the power of the diode. Diodes with a power of 1 W, 3 W or 5 V are sold, and 3 W is preferable for seedlings - 10-20 such lamps are used to illuminate a square meter of seedlings.

AlexGrower

FORUMHOUSE member

For additional lighting, you need 10-20 of them per square meter with a distance to seedlings of no more than 10-15 cm. Or for all your 2 m² 4-8 long trays (which are 36 W each), with the same distance to the sheet. You can up to 20 cm, see the state of the plants.

FORUMHOUSE user Lifted, a great expert in the issue of supplementary lighting of seedlings, empirically derived the formula:

about 50 1W LEDs are required per square meter of seedlings.

How to calculate distance from seedlings

Illumination is calculated as follows: it is inversely proportional to the square of the distance from the lamp to the surface, and if you move the lamp, which hung 25 cm from the seedlings, by 50 cm, then the illumination will decrease by 4 times. The angle of the lamp is also important here: you can draw an analogy with the sun, which shines brighter at its zenith than hanging over the horizon. It is necessary to adjust the distance of the phytolamp, checking the well-being of the seedlings, but this is quite a working table:

On average, it is recommended to supplement the seedlings with phytolamps for 8-13 hours a day. To ensure that all the light is delivered to its intended purpose, foil is glued over the lamps.

conclusions

In the climate of most Russian regions, supplementary lighting is necessary for both seedlings and indoor plants. For seedlings, the blue and red colors of the spectrum are primarily important. LED lamps will allow you to select the desired spectrum and select the optimal mode.

Are you also growing seedlings? Press your finger!

You can make a phytolamp for seedlings with your own hands, and such a device will be several times cheaper than a purchased one. At FORUMHOUSE we told in detail how make a budget fitolamp with your own hands. find out an easy way to grow seedlings in snails and optimal landing dates according to the lunar calendar. Watch the video on how to temper and feed properly adult seedlings.