In a 2017 Leafly article on cannabis bonsai, “Growing Cannabis with Bonsai: Separating Fact from Fiction“, author Rae Lland discussed the emerging trend of growing cannabis bonsai trees and interviewed Scott Chad, self-proclaimed “Bonsai person” and president of the Golden State Bonsai Federation on the possibilities of growing cannabis bonsai. The article essentially finished with a question and to us, a challenge:
Our multi-season cannabis bonsai
Earlier on in our project we had the chance to grow a multi-season bonsai by bringing it back into the spring/summer light cycle after flowering and partial harvest. Photoperiod varieties determine their place in the seasonal cycle by the amount of time they spend in daylight in order to fully mature and successfully reproduce before winter.
By controlling light cycles with indoor lighting, a photoperiod cannabis plant can be convinced that it is perpetually mid-summer, causing it to focus on growing large branches, leaves and stems. The light cycle for this type of growth, known as the vegetative phase, varies widely from grower preferences and strain needs quite widely, but a common example would be around 18 hours of light per 24 hour period.
After about four months in the vegetative phase, we flipped the lights from 20 hours down to 12 on, 12 off. This imitates the shortened days that cannabis senses to trigger the flowering process, where the plant’s focus switches from branches and leaves to actual reproductive flowers. The plant grows more dense rather than outward, producing many calyces/bracts to receive pollen, as seen at the end of 2019.
After harvesting the majority of the colas, we left a few flowers often referred to as ‘popcorn nugs’ for their size, as well as remaining leaves to support photosynthesis and hold the bonsai over while it recovers and works on producing new shoots.
This is when the plant is reverted into the summer growth schedule. We switched the lights to being on 24 hours a day, and fed nitrogen-rich nutrients, as well as beneficial bacteria and fungal cultures, further aiding the rapid transition back into vegetative growth.
After a few months of revegging under 20 hours of light, the remaining flowers dried completely and eventually withered away while new branches grew outward again.
As a species, Cannabis L. Sativa has yet to be fully accepted as a formal bonsai medium by many practitioners of the art. This is due to a number of reasons, most of which we believe come from simple misunderstanding around the species and the techniques that can be successfully applied to it. Scott Chadd summed up his perspective on the matter:
We would argue that it has unique characteristics, from a vast spectrum of fragrance and color, to microscopic, molecular complexity, quick to influence metabolism, fast growth rate, and ability to control proportion. These commonly held beliefs around the plant prevent many from seeing its potential as a viable species to help people practice bonsai, so we have been working toward proving that it is indeed a great medium for bonsai cultivation.
It’s a challenge, but the lifecycle can be manipulated to grow a single plant for years, as @Budzaiofficial demonstrates entirely in the vegetative stage
Can be multi-season
There has been very little formal research into the maximum lifespan of cannabis, but it has been said that with the right care they can last decades. Yet it remains one of the most challenging feats.
Vigorous growth can actually be slowed through metabolic control: a small pot restricts growth through informing sensory roots, and moderating the strength of light appropriately will reduce the number of total photons reaching the plant from which they use to determine at what rate to grow.
Curves can be trained into the branches
We would argue that it is graceful, can be anything but angular, and that curves can easily be formed. It is not fastigated if trained organically and branches selected and trained from a young age. Alternation of nodes further reduces the strength of the natural geometry, and the process of revegetation radically randomizes the production and placement of new growths, further distancing from its wild fastigated form.
Nutrient and water intake, metabolism, internode and leaf size all slow in response to these environmental conditions. It’s possible to have a plant of just a few months with leaves 3 times the size of one of our 1 year old bonsai through leaf size reduction techniques such as regrowth and heavy pruning in a small pot and subjecting it to waves of regrowth and pruning, as well as growing branches from branches rather than the main trunk in many cases.
Possible leaf-size reduction
Leaf size reduction of cannabis is a really interesting topic and one of the goals when growing cannabonsai. It is a common misconception that mature cannabis cannot grow small leaves. A thriving, untrained cannabis trunk can easily sproud leaves that exceed the size of a dinner plate, and young plant often grow fan leaves in excess of 6 inches. the leaves on our manifolded roots on rock are just around one inch long, after slowing the metabolism and training it through pot size reduction and five or size rounds of manifolding.
The trunk of our largest bonsai, exceeded 2 inches in diameter, while the leaves were around the same size. It’s all to do with metabolic control, and training and cutting branches back to thicken stumps in relation as they grow older.
@Golddustfarms has a great example of a well tapered and thick trunk and root crown system. It’s aged, the trunk thickens at the base and tapers at the top with a few thinner branches stretching outward.
By 2021 there are a number of photoperiod cannabis bonsai growers, some really pushing boundaries. Our goal has always been to explore common ground, experiment with possibilities, to demonstrate that this species is a great medium for bonsai cultivation by documenting and sharing our experiences with the world.
So in conclusion, we would argue you CAN grow bonsai with cannabis!