Gānjā
into the weeds
Ayurvedic name of Gānjā is Vijaya.
Vi-Jaya means vishesha jaya, or a particular type of specialized victory. Hence the yogic use of ganja is a vi-dhi or a particular technique for victory on the spiritual path.
As a side note, in contrast, Jaya is more than a technique per se, rather a total transformation of base identity, a complete victory over our base self.
Yogic Utility
Use of ganja, or weed, takes the Mind into psychic wormholes, tunneling into some dark crevices, giving us a different perspective on reality.
Going down deep Mind holes works to clear the psyche of its blockages (psychic viruses), as long as there is awareness during the trip, else it becomes simply a mindless experience which breeds addiction.
Since the practice of Yoga requires the Mind to be fully present, the use of ganja during Meditation is advanced practice, because for a novice it is almost impossible stay fully aware on the trip.
We can imagine how difficult a practice it could be to add ganja to Meditation, because even in normal, substance-free meditation we are only occasionally able to catch our Mind as it takes off into its own addictive Thought Streams!
The Rāmāyana of Gānjā
Recall that Jaya & Vijaya were sent to earth as Rāvana & Kumbhakarana
Kumbhakarana had :
uncontrollably deep sleep
a voracious appetite when awakened
chaotic actions
Lethargy, uncontrollable munchies, and hyperactive mind are well known outcomes of gānjā intake too !
Addiction is to be avoided so as to give kumbhakarana moksha - thus he returns to Vaikuntha as the dwāra pălaka, in constant proximity with divinity of Perumāl.
Thus gānjā is to be consumed mindfully - transmuting its negative qualities as part of yoga practice :
we should be alert without sleep
and should not eat through the effects stage.
During Shivarātri for example
Or else Kumbhakarana effect perpetuates, addiction ensues, and we do not get moksha.
Asuric depths
It's also a very good idea to grow our own plants because these are Conscious Beings and their Prāna energies get attuned to us through coevolution, just like any other medicinal plant, and all food, and even the whole Universe as we speak.
The industrialization of ganja essentially deepens the potential rākshasa into an asura virus, taking over the entire societal mind and immersing it into the lower lokas.
How to extract the divinity in asuric mind is through the difficult process of Samudra manthan - in this case rehab therapy clinics !!