We often measure the quality of cannabis by multiple things. Think about structure and appearance but even more important: Potency, effect, smell and taste. A positive view on these aspects is what most people consider as “good weed”. These characteristics are mostly being influenced by the amount of cannabinoïds and terpenes which aren’t only genetical aspects. You can actually have some influence on these levels by using certain light and minerals.
Very high rated cannabis, mostly sold in dispensaries and coffeeshops always have a huge trichome/resin production which makes it highly potent. With a lot of trichomes, comes a lot of psychoactive ingredients and terpenes. The amount of these trichomes are only partially genetically determined as they could be influenced by light and minerals. Next to that: The production of THC works together with the production of certain terpenes. This means that more terpenes will result in a better taste and smell but also a bigger amount of THC. Let me explain:
There is an important connection between terpene production and THC/CBD levels. Let’s begin with THC. The THC production process has 2 other side products: Limonene and pinene. So these terpenes are a result of the THC being made in the trichomes. This is why you almost always notice some kind of citrus-smell in high THC strains.
Another process in trichomes that has influence on certain terpene levels is the production of CBD, a well known substance with medicinal benefits. When producing CBD, A substance called Cannabigerol (CBG) is transformed to CBD and the Monoterpene: Mycreen. So High level CBD strains contain most of the time lots of Mycreen.
Why do minerals and light have influence on all these levels?
A cannabis plant requires multiple enzymes to produce terpenes and cannabinoïds. To stimulate the production of these enzymes, the plant will need certain light waves. To be precisely: UVB light which is found in the ultraviolet spectrum. Also: Cannabinoids are somehow a kind of defendsystem of the plant. Thats another reason why UVB light stimulates the enzymes that produces these cannabinoids as too much UVB could be harmfull. (think about sunburn)
Minerals also play a huge rol in the production of terpenes because without certain minerals, it’s impossible to produce most terpenes. For the terpene production process, the enzymes require a bivalent ion to make certain chemical connections for terpene production. The magnesium and manganese ion are bivalent and required to create almost all terpenes in cannabis.
Because the terpene and cannabinoïd production is so connected, a shortage of these bivalent ions in your plant nutrition will lead to decreased production of THC and CBD. Always keep that in mind when you are looking for a bloom nutrition!
Importance of red light
We have just learned that certain waves (Ultraviolet/UVB) in the colour spectrum will lead to a better production of cannabinoïds and terpenes. But there is something else about the colour of the light that could improve the terpene production. To be more precisely the colour red!
If you leave out certain red colour frequencies of the spectrum, at the end of the blooming phase, you are able to boost the terpene production just before harvesting. That will increase the taste and smell of your product significantly because the breakdown of terpenes depends on signals the plant gets from red and far-red light.
However it’s not an option to just cut off all the red light during a large part of the blooming phase. Your plant will still need the red colour to live and grow so by cutting out of you wall harm your plant eventually. Thats why lamps specifically made for blooming will still contain the red colour frequency.
How should I do it then?
If you would leave out the red colours during the last 72 hours of blooming, you would already recognize a a difference in terpene levels (in smell and taste). You could do this by simply turning your LED lamp into “grow” mode or replace your HPS with a MH lamp. By doing this your plant won’t breakdown any terpenes any more as this is triggered by red ligh. However the terpene production keeps going one wich will lead to some extra taste and smell at the end of the grow!
Got more tips and tricks on how to improve the quality of your cannabis? Feel free to leave a comment below!