Prohibition has had the unintended consequence of accelerating innovation in Cannabis growing.
Most high-quality Cannabis sold in the US today is grown indoors. Without prohibition, and the escalation of the War on Drugs in the ‘70s, it is hard to imagine that people would have decided to start growing Cannabis indoors. However, reluctant indoor growers in the US (and Amsterdam) have brought about many innovations, both in technology and technique, that have greatly improved the quality of Cannabis on the market.
First, a basic lesson in growing Cannabis.
The Cannabis that people use is only the flowers of female plants. Cannabis plants will start flowering as soon as they receive 12 hours or more of darkness each day (simulating fall). With 16-24 hours of light per day they can keep growing indefinitely in a vegetative phase. The longer the vegetative phase, and the more intense the inputs (light, oxygen, CO2, nutrients) the larger the plants and their flowers will be.
1970s: Sinsemilla, the first modern growing innovation
Sometime in the ‘70s, when most Cannabis was still grown outdoors, people realized that if you remove the male Cannabis plants — which are basically worthless — before they pollinate female plants the female buds grow bigger and don’t produce pesky seeds. By the late ‘70s, most Cannabis grown commercially was sinsemilla (spanish for “without seeds”). While perfecting cultivation techniques growers also started breeding strains of cannabis that were more suitable for the shorter growing season of northern latitudes. With growing techniques and genetics improving, cultivators started improving other attributes of Cannabis such as appearance, taste, color, and smell.
1980s: The move indoors
As large commercial cultivators started appearing, especially in Northern California, law enforcement started getting better at busting growers. Buoyed by growing budgets during the “Just Say No” era, law enforcement started using planes and helicopters to detect and raid outdoor Cannabis cultivators. It was at this time that cultivators reluctantly started growing indoors. The price-support from prohibition meant that growers could afford the extra costs of growing indoors, but its still important to acknowledge the high financial and environmental costs of growing Cannabis indoors. Its estimated that 1% of all electricity in the US is used for Cannabis cultivation.
Forced to move indoors, cultivators started embracing the advantages it affords; the biggest being control. Indoors, a grower can experiment and find the exact conditions that allow a particular strain to thrive. Once ideal conditions have been found a grower can replicate them for each harvest to produce a more consistent product. Later, the internet helped growers share their learnings more widely.
Not beholden to the earth’s rotation, an indoor grower can produce three or even four harvests in a single year. Techniques like Sea of Green, which are only practical indoors, allow a grower to quickly produce a large and tightly-controlled harvest. Sea of Green involves planting clones at a very high density and switching them to the flowering stage almost right away. This produces a dense canopy of plants that focus most of their energy on producing a large flower and nothing else. While yield per plant is lower than other techniques, yield per square foot and per kilowatt hour is very high.
The second main advantage of growing indoors is it’s easier to keep out contaminants like pests, mildew, pollen, and mold. This is particularly important for medical Cannabis patients who may have a compromised immune system.
1990s: Technology advances
With many Cannabis growers now indoors, and given the high dollar value of a Cannabis plant, much effort was invested in developing indoor cultivation technologies. A typical indoor grow today will feature banks of 1000W high-intensity discharge lamps enclosed in ventilated hoods. High power fans replace the volume of air in a grow-room every few minutes. Intake air is filtered to remove contaminants and exhaust air passes through an activated carbon filter to remove any odor. Equipment to monitor and control temperature, CO2, and humidity can also be added to further improve a grow. A large scale operation will have separate rooms for clones, vegetating plants, and flowering plants at different stages. A staggered harvest like this is a must for any business that needs to have inventory year-round.
Hydroponics
While Cannabis growers certainly didn’t invent hydroponics, the industry has supported a lot of advancements in the field, especially at the consumer and prosumer level.
There are a variety of hydroponics techniques used to cultivate Cannabis, which could be its own blog post. The main point about hydroponics is it’s a great way to boost the quality and output of a grow, but it requires more upfront investment and is easier to mess up and destroy a crop. Hydroponic cultivation can maximize yield per square foot, which is especially important for people growing in their basement or other space constraints. One thing we will keep an eye on over the next decade is how many large-scale commercial cultivators will continue to use hydroponics and how many will switch back to simpler methods.
Today: Regulation
Medical and adult-use Cannabis legalization is influencing cultivation techniques in two ways. First, until Cannabis is federally legal all Cannabis for a state market must be grown in-state. In a state like Maine or Washington this means that most Cannabis has to be grown indoors. Some states also specifically require indoor cultivation.
Second, many state medical programs cap the number of plants a dispensary can grow (6 per registered patient in Colorado’s medical market). This favors technology and techniques that maximize yield per plant. In these states growers are less likely to use Sea of Green, instead opting for techniques that encourage each plant to produce more than one main bud (called the cola).
The future
It’s hard to predict how legalization will play out over the next decade, but its reasonable to assume some aspects of Cannabis cultivation will change. Many believe that indoor cultivators will move to highly-controlled greenhouses (known as Controlled-Environment Agriculture). In a controlled greenhouse you get all the advantages of growing indoors but use free light from the sun. A sophisticated greenhouse will use both supplemental lighting and light deprivation to enable the same control over light/dark cycles that you get indoors.
After greenhouses another technology to keep an eye on is LED lighting. Cannabis cultivators are only just starting to experiment with LED lighting, but as the technology improves the advantages are huge. Besides drastically reducing electricity costs LED lights don’t have to be cooled like a high-intensity discharge light does. This greatly simplifies a grow room’s ventilation system.
Most newly-legal states explicitly favor large-scale businesses through high license fees and extensive regulations. It’s likely that these large cultivators will invest more in automation technology. Environmental conditions can be remotely monitored and controlled; watering and nutrient dosing can be automated with drip systems. Increased competition and downward price pressure will also force cultivators to find ways to reduce their costs per gram.
The high price of Cannabis (thanks to prohibition) has allowed it to be grown with more care and technology than it otherwise would have. Some of what we have learned in this environment will be useless as prices start to drop, but there are certainly many innovations that are here to stay. The cultivators that succeed in the future will be the ones who are able to invest in technology to dramatically reduce their cost of production while maintaining the quality that consumers have become accustomed to.
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I think it’s good to study, and improve ways for growing this wonderfully medicinal plant~