Light Spectrum Adapted To Cannabis
About the spectrum of lighting, cannabis plants need mainly blue light (450-500nm) during the stage of growth and red light (610-750nm) during flowering.
During root rooting and seedling growth , most growers use simple fluorescent tubes or blue CFL bulbs . In a culture space of sufficient size, it is also possible to use MH bulbs which possess the same blue / white spectrum suitable for growth, but with a higher power than CFL. In this way the plant becomes stronger and stronger, thus preparing for abundant flowering .
Lighting with a red spectrum is used for flowering plants. Red is the color that best replicates the outside natural spectrum during the fall months, when marihuana flowers bloom naturally. The HPS lamps are used the most, followed by LED systems that offer good results, a lower power consumption and low heat emission, which is the main drawback of the high pressure sodium systems (HPS).
On the contrary, green light and cannabis do not conflict because it does not affect plants, so it is the spectrum used by growers who wish to work in the growing area when the lights are extinguished without Causing stress to blooming plants.
Illumination Systems For Cannabis
Fluorescent and CFL
This is the ideal type of lighting for rooting cuttings or for young seedlings . The low power required, the low power consumption and the low heat emitted make it an excellent option during these steps. There are conventional lighting systems with fluorescent tubes, or low CFL (Compact fluorescent light) bulbs, which are also fluorescent tubes but bulb shaped, with the typical lampholder on the reflector. CFLs have a built-in ballast, so you just have to connect them to the reflector and connect it to the mains to make the system work. Normally, fluorescents offer a power of between 18 and 55W per tube, while CFLs are only available in 100, 125, 200 or 250W (also available with a red spectrum for flowering).
Do not hesitate to read our article on the cultivation of cannabis with CFL lamps in order to know everything about this type of lighting.
Metal Halide or MH Lamps
If an explosive growth of plants during the vegetative phase is desired, MH bulbs are the best option. Their spectrum is perfect for this stage and we can find MH bulbs with a power superior to fluorescent and other CFL. This type of bulb needs a ballast to operate, compatible with both the MH bulbs and the HPS (High Pressure Sodium) bulbs, which are generally used during flowering.If the same ballast is used for growth and flowering, the watts must be taken into account, using, for example, bulbs and ballasts of the same power. These bulbs are usually available in 250, 400 or 600W.
These ampoules also offer excellent results during the stretch period of early flowering (first 2-3 weeks of flowering), they limit the stretching of the plants compared to a HPS, and create a more compact structure , Ideal for abundant flowering.
High pressure sodium or HPS vapor bulbs
This is the queen of flowering rooms, although in recent years the LED panels have gained ground. We can find HPS bulbs specifically designed for flowering, or of mixed bulbs (dual spectrum), used both in growth and flowering. It is generally accepted that this is the type of lighting that offers the most interesting final output. Its main disadvantage however lies in the production of heat emitted once in operation. The spectrum is also not expected for satisfactory growth. To reduce the heat emitted, some growers use cooltube reflectors , reflectors cooled by air, which, when connected to an extractor, reduce the environmental temperature by a few degrees. In general, HPS bulbs are available in 250, 400, 600 and 1000w. The 250W bulbs are suitable for a 60 x 60 cm or 80 x 80 cm growing space, 400W bulbs for a 100 x 100 cm space, and 600W bulbs for about 120 x 120 cm.
Our next article on SOG culture technique will give you more guidance on how to make plants bloom with a HPS bulb.
Cannabis And LED Panels
The LED bulbs (or Light Emitting Diode shorted by mbakecheng) are increasingly popular in the world of home growing, they indeed offer similar results in HPS bulbs, but with consumption and heat emission much lower. These lighting systems have improved in recent years, delivering results unthinkable some time ago. Their main disadvantage is the price, which although it is quickly recovered on the monthly electricity bill given the lower consumption, remains too high for many budgets. They generate virtually no heat, so it is not useful to use powerful extractors for the culture room, whether in a cabinet cabinet or in small spaces. It may be necessary to add some heating during the colder months of the year, using thermal mats or heating cables , etc. There are on the market panels of different powers, from 90 to 280W, or even more.
You can read this culture follow-up with LED panels in which we introduce the culture with this lighting system.
UV Lighting and Cannabis Resin
The use of ultraviolet light during the cultivation of cannabis has existed for a long time. According to the most commonly accepted theory, marihuana produces resin or trichomes in particular to protect against high solar intensities and UV rays emitted by the sun.Since indoor lighting does not (or very little) emit UV light, we can assume that combining conventional light bulbs with UV light willincrease resin production (cannabinoids, terpenes , Etc.) and therefore the power of plants. Some farmers also add such an argument maturation of trichomes faster. Even so, since the majority of trials are not carried out with scientific rigor , it is not possible to be affirmative about their benefits during an indoor cannabis culture.
If you wish to experiment with this type of lighting, it will be necessary to take into account that UVB (and not UVA) and low power rays, such as those used for reptiles, will have to be used. These rays can produce skin cancer and severe eye damage, so we recommend extreme caution when using them .
Plasma Lamps For The Cultivation Of Cannabis
The plasma lighting systems or HEP (High Efficiency Plasma) are increasingly talking about them. Although they promise greater luminous efficacy compared to HPS bulbs, they present various problems that explain why they are generally not used for cultivation.Indeed they present illuminating spectra unsuitable for abundant flowering, emit UVC rays (very harmful for health), have a high price and cause interference with the signals wifi.
For lack of research and development, it will be necessary to be satisfied with some cultures realized with this type of lighting (generally in complements of LED), which seemed to offer promising results.
We hope that this article will help you clarify some doubts . Thank you and see you soon !