How to arrange lighting for hemp
When growing outdoors, it is important to plant seedlings on time, everything else is taken care of by nature. But indoors, the grower handles the lighting. He buys lamps, adjusts the light and controls the length of the daylight hours. Below we will elaborate on what the grower needs to know about this.
What is the relationship between light spectra and cannabis development
Cannabis development is influenced by three light spectrums:
Blue - reduces the distance between nodes. The plant builds up a good green mass, bushes, and does not grow in height. More tillering - more yield.
Red - promotes the growth of bushes, the formation and maturation of cones.
Green - develops stems and leaves.
At the vegetation stage, lamps with a predominant blue spectrum are suitable, and during flowering - with orange.
Which lamps to choose for indoor
DRI - metal halide lamp with a blue spectrum. Relatively inexpensive option for vega. Of the pronounced minuses - it heats up a lot and consumes a lot of energy.
HPS - sodium lamp with a warm spectrum. Used at the flowering stage. Complements the DRI lamp - it is also inexpensive, it heats up a lot and is characterized by high power consumption. Working resource - up to 15 thousand hours.
ESL or CFL is a fluorescent lamp suitable for seedlings, clones and very compact autos. Optimal spectrum for cannabis development, but insufficient power and light output, therefore only suitable for small boxes. The lamp heats up slightly, has a low energy intensity. Service life - up to 20 thousand hours.
LED - LED lamp, the main competitor of DRI and HPS. Suitable for vega and flowering, consumes little energy, does not heat up. It costs more than DRI / HPS, but it also works many times longer - up to 50 thousand hours. The best for cannabis will be ICE with a purple spectrum.
An ordinary incandescent lamp is not suitable for hemp, because it does not have a full light spectrum (white light) and, in principle, cannot stimulate the plant's photosynthesis, and hence its development.
Light mode and lamp placement
HPS and DRI lamps get very hot during operation and, in order not to burn the plant, they must be at a distance of 50 centimeters from its top. Fluorescent lamps, due to low light output, on the contrary, need to be placed closer to the plants. To only germinated seeds at a distance of 10 centimeters, and when the sprout gets stronger, lower it down by 5 centimeters. The light should be uniform, so several lamps are placed in rectangular boxes. Install them so that you can adjust the height as the bush grows.
Optimal during the growing season for photoperiod cannabis is considered to be 18-hour daylight hours. It lasts at least 3-4 weeks. The longer the vega, the more green mass the bush will grow and the greater the yield. The transition to flowering for photoperiod occurs along with a decrease in daylight hours and the replacement of lamps of a suitable spectrum (if a metal halide was used). The plant begins to bloom about a week after the reduction of daylight hours to 12 hours.
Flowering in autoflowering cannabis does not depend on the length of the day. It can be constantly kept at 18-20 hours, but it is also worth replacing the blue spectrum with red or orange. You'll know you've overdone the light if the cannabis leaves turn yellow and its development slows down.
How to arrange lighting for hemp