Controlling your grow environment doesn’t start when you germinate your first seeds, it starts before you build your grow. There are steps you can take that will have a significant impact on mold growth and contamination, and these will vary based on the grow environment you choose.
Below is a roadmap to where each grow environment stands in terms of mold and contamination risk, and simple steps you can take to mitigate these factors.
The benefits of an outdoor grow are significant – using natural sunlight to grow plants is both inexpensive and environmentally sound. However, it allows the least amount of control and makes plants susceptible to weather conditions and outdoor contaminants including dust, wind, rain and insects. Depending on humidity and precipitation levels, mold can be a big issue as well.
When selecting an outdoor area for a cannabis farm, there are two important factors to consider: location and neighboring farmland. Geographical environments and sub-climates vary and once you have purchased land, you are committed, so be sure to consider these factors prior to purchase.
While arid desert climates have abundant sunlight and long growing seasons, flat, dry lands are subject to dust-storms, flash floods and exceedingly high winds that can damage crops. Conversely, more protected areas often have high humidity and rainfall late in the season, which can create huge issues with bud rot and mold. Neighboring farms also have an impact on your grow, so be sure to find out what they cultivate, what they spray, their harvest schedule and how they run their operation. Large farming equipment kicks up a lot of contaminant-laden dust and can damage crops by displacing insects to your farm if they harvest before you. Pesticide drift is also a major issue as even tiny amounts from a neighbor’s farm can cause your crops to fail testing, depending on what state you are in.
With outdoor grow environments always at the mercy of Mother Nature, any cultivator is wise to control contamination potential on the ground. Cover soil and protect your crop by planting cover crops and laying plastic mulch on as much ground as reasonable. In many cases it makes sense to irrigate uncultivated parts of your farm just to keep dust down.
Greenhouses are the future of cannabis cultivation. They allow growers to capture the full spectrum and power of the sun while lessening environmental impact and operating expenses, while still being able to precisely control the environment to grow great cannabis. With recent advancements in greenhouse technology such as automated control systems, positive pressure, geothermal heating or cooling and LED supplemental lighting, greenhouses are the future. However, older or economy greenhouses that take in unfiltered air from outside still have a medium amount of mold and contamination risk.
Before building your greenhouse, study the area while taking into account climate, weather conditions and sun exposure. Excessively windy areas can blow in contaminants, and extremely hot climates make cooling the greenhouse interior a challenging and costly endeavor.
There are several simple operational tactics to reduce contaminants in a greenhouse. Add a thrip screen to keep insects out, thoroughly clean pad walls with an oxidizing agent after each cycle, and keep plants at least 10 feet from pad walls. Plan to flip the entire greenhouse at once so that you can clean the greenhouse top to bottom before your next crop. A continuous harvest in your greenhouse allows contaminants to jump from one plant to the next and reduces the ability to control your environment and eliminate problems at the end of a cycle. Lastly, open shade curtains slowly in the morning. This prevents temperature inversion and condensation, which can cause water drops to fall from the ceiling and transfer contaminants onto plants below.
An indoor environment offers ultimate control to any grow operation. Cultivators can grow high-quality cannabis with the smallest potential for yeast and mold growth. Unfortunately, indoor environments are extremely expensive, inefficient and environmentally costly.
With indoor grow environments, keeping mold and contaminants at bay comes down to following a regimented plan that keeps all grow aspects clean and in order. To keep your grow environment clean, change HVAC filters multiple times a month. It’s also important to install HEPA filters and UV lights in HVAC systems to further reduce contamination threats. Clearly mark air returns if they are near the ground and keep those areas free of clutter. They are the lungs of your grow. Also, stop using brooms in the grow space. They stir up a lot of contaminants that have settled to the floor. Instead, use HEPA filter backpack vacuums or install a central vacuum system. Set up a “dirty room” for anything messy on a separate HVAC system, and be sure to thoroughly clean pots after every harvest cycle.
Editor’s note: This article should serve as a foundation of knowledge for yeast and mold in cannabis. Beginning in January 2018, we will publish a series of articles focused entirely on yeast and mold, discussing topics such as TYMC testing, preventing yeast and mold in cultivation and treatment methods to reduce yeast and mold.
Cannabis stakeholders, including cultivators, extractors, brokers, distributors and consumers, have been active in the shadows for decades. With the legalization of recreational adult use in several states, and more on the way, safety of the distributed product is one of the main concerns for regulators and the public. Currently, Colorado1, Nevada and Canada2 require total yeast and mold count (TYMC) compliance testing to evaluate whether or not cannabis is safe for human consumption. As the cannabis industry matures, it is likely that TYMC or other stringent testing for yeast and mold will be adopted in the increasingly regulated medical and recreational markets.
The goal of this article is to provide general information on yeast and mold, and to explain why TYMC is an important indicator in determining cannabis safety.
Yeast & Mold
Yeast and mold are members of the fungi family. Fungus, widespread in nature, can be found in the air, water, soil, vegetation and in decaying matter. The types of fungus found in different geographic regions vary based upon humidity, soil and other environmental conditions. In general, fungi can grow in a wide range of pH environments and temperatures, and can survive in harsh conditions that bacteria cannot. They are not able to produce their own food like plants, and survive by breaking down material from their surroundings into nutrients. Mold cannot thrive in an environment with limited oxygen, while yeast is able to grow with or without oxygen. Most molds, if grown for a long enough period, can be detected visually, while yeast growth is usually detected by off-flavor and fermentation.
Due to their versatility, it is rare to find a place or surface that is naturally free of fungi or their spores. Damp conditions, poor air quality and darker areas are inviting environments for yeast and mold growth.
Cannabis plants are grown in both indoor and outdoor conditions. Plants grown outdoors are exposed to wider ranges and larger populations of fungal species compared to indoor plants. However, factors such as improper watering, the type of soil and fertilizer and poor air circulation can all increase the chance of mold growth in indoor environments. Moreover, secondary contamination is a prevalent risk from human handling during harvest and trimming for both indoor and outdoor-grown cannabis. If humidity and temperature levels of drying and curing rooms are not carefully controlled, the final product could also easily develop fungi or their growth by-product.
What is TYMC?
TYMC, or total yeast and mold count, is the number of colony forming units present per gram of product (CFU/g). A colony forming unit is the scientific means of counting and reporting the population of live bacteria or yeast and mold in a product. To determine the count, the cannabis sample is plated on a petri dish which is then incubated at a specific temperature for three to five days. During this time, the yeast and mold present will grow and reproduce. Each colony, which represents an individual or a group of yeast and mold, produces one spot on the petri dish. Each spot is considered one colony forming unit.
Why is TYMC Measured?
TYMC is an indicator of the overall cleanliness of the product’s life cycle: growing environment, processing conditions, material handling and storage facilities. Mold by itself is not considered “bad,” but having a high mold count, as measured by TYMC, is alarming and could be detrimental to both consumers and cultivators.
The vast majority of mold and yeast present in the environment are indeed harmless, and even useful to humans. Some fungi are used commercially in production of fermented food, industrial alcohol, biodegradation of waste material and the production of antibiotics and enzymes, such as penicillin and proteases. However, certain fungi cause food spoilage and the production of mycotoxin, a fungal growth by-product that is toxic to humans and animals. Humans absorb mycotoxins through inhalation, skin contact and ingestion. Unfortunately, mycotoxins are very stable and withstand both freezing and cooking temperatures. One way to reduce mycotoxin levels in a product is to have a low TYMC.
Yeast and mold have been found to be prevalent in cannabis in both current and previous case studies. In a 2017 UC Davis study, 20 marijuana samples obtained from Northern California dispensaries were found to contain several yeast and mold species, including Cryptococcus, Mucor, Aspergillus fumigatus, Aspergillus niger, and Aspergillus flavus.3 The same results were reported in 1983, when marijuana samples collected from 14 cannabis smokers were analyzed. All of the above mold species in the 2017 study were present in 13 out of 14 marijuana samples.4
Aspergillus species niger, flavus, and fumigatus are known for aflatoxin production, a type of dangerous mycotoxin that can be lethal.5 Once a patient smokes and/or ingests cannabis with mold, the toxins and/or spores can thrive inside the lungs and body.6, 7 There are documented fatalities and complications in immunocompromised patients smoking cannabis with mold, including patients with HIV and other autoimmune diseases, as well as the elderly.8, 9, 10, 11
For this reason, regulations exist to limit the allowable TYMC counts for purposes of protecting consumer safety. At the time of writing this article, the acceptable limit for TYMC in cannabis plant material in Colorado, Nevada and Canada is ≤10,000 CFU/g. Washington state requires a mycotoxin test.12 California is looking into testing for specific Aspergillus species as a part of their requirement. As the cannabis industry continues to grow and advance, it is likely that additional states will adopt some form of TYMC testing into their regulatory testing requirements.
Centre for Disease control and prevention. 2004 Outbreak of Aflatoxin Poisoning – Eastern and central provinces, Kenya, Jan – July 2004. Morbidity and mortality weekly report.. Sep 3, 2004: 53(34): 790-793
Cescon DW, Page AV, Richardson S, Moore MJ, Boerner S, Gold WL. 2008. Invasive pulmonary Aspergillosis associated with marijuana use in a man with colorectal cancer. Diagnosis in Oncology. 26(13): 2214-2215.
Szyper-Kravits M, Lang R, Manor Y, Lahav M. 2001 Early invasive pulmonary aspergillosis in a leukemia patient linked to aspergillus contaminated marijuana smoking. Leukemia Lymphoma 42(6): 1433 – 1437.
Verweii PE, Kerremans JJ, Voss A, F.G. Meis M. 2000. Fungal contamination of Tobacco and Marijuana. JAMA 2000 284(22): 2875.
Ruchlemer R, Amit-Kohn M, Raveh D, Hanus L. 2015. Inhaled medicinal cannabis and the immunocompromised patient. Support Care Cancer. 23(3):819-822.
McPartland JM, Pruitt PL. 1997. Medical Marijuana and its use by the immunocompromised. Alternative Therapies in Health and Medicine. 3 (3): 39-45.
Hamadeh R, Ardehali A, Locksley RM, York MK. 1983. Fatal aspergillosis associated with smoking contaminated marijuana, in a marrow transplant recipient. Chest. 94(2): 432-433.
Maintaining an environment that supports cultivation and keeps plants healthy is not an easy task. In cannabis growing, there are a variety of factors that greenhouse managers and personnel must monitor to ensure that their plants are in a healthy environment that fosters growth and development. Temperature, humidity, lighting and CO2 levels are a few of the conditions that need to be tailored to each cannabis greenhouse operation. However, it can be difficult to constantly monitor the status of your equipment and the greenhouse environment, especially after hours or during the off-season.
A remote monitoring system that’s properly selected and installed can help greenhouse managers keep their cannabis plants healthy, multiply their yields and increase return on investment. This type of system also helps operators identify patterns and trends in environmental conditions and get insight into larger issues that can prevent problems before they arise.
Here are some tips on key conditions to monitor and what you need to consider when selecting a monitoring system for your cannabis greenhouse operation:
Temperature plays a crucial role in any cannabis grow operation. The climate in your greenhouse must be warm enough to nurture photosynthesis and the growth of cannabis plants. Setting the incorrect temperature will significantly impact the potential yield of the plant and the rate at which it develops. A temperature too low will slow the growth of the cannabis, but too hot can lead to heat stress for your plants. The ideal temperature for a standard greenhouse is between 70 and 80 degrees Fahrenheit. However, depending on the stage of plant and desired growth densities, the temperature of the greenhouse needs to be adjusted accordingly.
Humidity directly affects plant photosynthesis and transpiration, so controlling humidity is vital in greenhouse growing. The ideal relative humidity (RH) for cannabis growth is around 60%. A low humidity level can cause water to evaporate too quickly for photosynthesis, while a humidity level that is too high can cause poor growth and possible mold and fungal disease. Monitoring the moisture content in the air of your greenhouse will help the plants during the transpiration process, increasing absorption of nutrients and overall health of the cannabis.
Your cannabis may be getting an abundance of natural light during the summer months, but maintaining adequate sunlight during the winter months can be a challenge. As a solution to this, many greenhouse managers equip their facilities with additional lights to supplement natural light during off-seasons or off-hours. To achieve the best possible yield, a cannabis plant in the budding stage should receive twelve hours of light each day, while other stages could require additional lighting. For example, the growth stage could require your cannabis to be exposed to sunlight for up to eighteen hours a day.
Like any other plant, cannabis requires CO2 to breathe. Greenhouse managers must set and monitor the CO2 levels in their facility to make sure that there is an adequate amount for the plants to develop, grow and be healthy. The amount of carbon dioxide required for your cannabis depends of the size of the facility and the amount of light the plants are receiving. However, a standard grow area for cannabis can maintain a CO2 range from 1000 to 1500 parts per million (PPM). A level below that threshold can result in slower growth of the plants, while a level above would lead to unused and wasted CO2.
Irrigation and Soil Moisture
One way to ensure a good yield from your cannabis is to water it regularly and monitor your soil moisture. Overwatering your plants can have the same effect, if not worse, than letting the soil become too dry. Plants’ roots need oxygen to survive, unlike leaves that breathe CO2, and when the soil is waterlogged the roots can’t provide their function. The lack of oxygen interferes with the roots’ nutrient uptake and photosynthesis causing the cannabis plant to wilt. The exact moisture content of the soil depends on the size of your greenhouse, temperature and humidity. Whether you hand water or are using a drip irrigation system, being aware of your soil moisture is vital to the long-term health of your cannabis.
Your greenhouse environment should mimic the ideal conditions in which cannabis plants flourish. With an indoor facility, you have the ability to control air circulation by venting hot air out and blowing fresh air in. Creating a circulation of air inside your greenhouse will increase your cannabis plant’s growth speed and yield. Additionally, an exhaust system helps control the temperature and humidity, while also preventing the invasion of mold and pests that thrive in hot, stagnant air.
When growing something of value, like cannabis, there will always be a threat of intruders. Whether your greenhouse is in a populated area or around hungry wildlife, any intruder could be detrimental to your overall yields and profit. Remote monitoring systems can give you peace of mind and instantly alert you when there is an unwanted presence in your greenhouse.
Knowing all the possible threats to your cannabis greenhouse helps you evaluate your specific needs, and ultimately identify the proper remote monitoring system.
Selecting the Right Monitoring System
Other factors to consider when choosing a monitoring system right for your operation include:
Base unit and sensors
Wireless or hardwired sensors
Communications to your site (Phone, cellular, Wi-Fi, etc.)
Programming and status checks
Return on investment
Base Units and Sensors
Each condition in your greenhouse that you want to monitor requires its own input on the base unit of the monitoring system. You must match your needs with the number of inputs available. A good fit for a smaller cannabis greenhouse may be a lower-cost, non-expandable monitoring system. However, larger facilities have many monitoring points and more people to alert when there’s a problem. If your cannabis operation is poised for growth, purchasing an expandable system could add value to the initial purchase because you wouldn’t have to replace your entire system in the future.
Your monitoring system should also have an internal rechargeable battery backup to ensure continuous monitoring and alerts in the event of a power outage. It is also recommended to have each base unit in a sheltered enclosure to protect it from moisture, dirt and other hazards.
Placement of sensors is also crucial. For example, temperature sensors in your greenhouse should be placed throughout the facility. They should be next to your thermostat and in the center of your greenhouse, preferably away from direct sunlight.
Wireless or Hardwired Sensors
Remote monitoring systems offer the option to have sensors hardwired directly to the base unit or sensors wirelessly connected. A hardwired monitoring system connects the sensors to the base device with wires. Generally, trenching long distances for wires is time consuming and costly. So alternatively, a wireless system uses built-in radio transmitters to communicate with the base unit. Some monitoring systems can accommodate a combination of hardwired and wireless sensors.
Communications to Your Site
Monitoring devices that use cellular communications must be registered on a wireless network (like Verizon or AT&T) before you can send or receive messages. Because cellular devices perform all communications over a wireless network, it is important that there be sufficient signal strength at the greenhouse. It is a good idea to check the signal quality in the area before purchasing a cellular product. If the cellular network has less than desirable coverage, it is possible to install an external antenna to help increase cellular signal.
When monitoring systems identify a change in status, they immediately send alerts to people on the contact list. If you don’t want all of your personnel to receive notifications at the same time, certain devices can be programmed to send alerts in a tiered fashion. It is important to consider the reach of the communications, so that you’ll be notified regardless of your locations. Multiple communications methods like phone, email and text provide extra assurance that you’ll get the alert. Also, note of the number of people the system can reach and if the system automatically cycles through the contact list until someone responds. Make sure the system allows for flexible scheduling so that it doesn’t send alarms to off-duty personnel.
Programming and Status Check
If you’re responsible for maintaining a commercial greenhouse facility, you want a system that will provide real-time status of all monitored conditions on demand. There are a few different ways to access your sensor readings. Options include calling to check status, viewing a web page, either on a local network or on the cloud, or accessing the information via an app on your mobile device. With a cloud-based system, the devices supervise themselves. This means if the internet or cellular connection goes down, the device will send an alarm to alert the appropriate personnel.
If you don’t select a cloud-based system, you will be limited to logging in through a local area network, which will allow you to make programming changes, access status conditions and review data logs. If internet connectivity is not available at your location, you will want to choose a cellular or phone system rather than Ethernet-based option.
Data history is valuable in identifying patterns and trends in your cannabis greenhouse conditions. Manually monitoring and recording environmental parameters takes a significant amount of personnel time and detracts from other important workplace demands. However, many monitoring systems automatically save information, recording tens of thousands of data points, dates and times. Cloud-based logging provides an unlimited number of records for users to view, graph, print and export data trends.
Analyzing data samples may lend insight to larger issues and prevent problems before they arise. For example, if the data log shows power fluctuations occurring at a regular time, it could be indicative of a more serious problem. Or, if the data shows signs of a ventilation fan or supplementary lighting beginning to malfunction, they can be repaired or replaced before total failure occurs.
Return On Investment
When deciding how much you should pay for a remote monitoring system, tally up the entire cost, fully installed with additional peripherals and sensors and any labor fees for installation. Then consider the value of your cannabis plant inventory and greenhouse equipment. Finally, factor in the cost of downtime, should an environmental event shut down your operation for a period of time.
Choosing the right greenhouse monitoring system and sensors could mean the difference between life and death for your cannabis plants. Understanding the conditions you need to watch and monitoring systems’ capabilities are they best way to protect your investment.
The modern chemical agricultural approach is based on the assumption that chemical science has discovered all facets of plant nutritional requirements. It is clear that the traditional NPK approach to plant/soil systems has its limitations, both from an ecological perspective and in terms of its ability to create nutrient-dense food.
Soil and plant systems have existed together for millions of years and have evolved the capacity to coexist in a way that is mutually beneficial. Plants have been fed and evolved with these biological and environmental stimuli over millennia.
Looking to the geologic record for evidence, we can see that it shows that invertebrates, fungi and early vascular plants appeared on land roughly 400 million years ago, the first seed bearing plants about 360 million years ago and the first flowering plants 130 million years ago. What does this mean? The soil food web has been in existence for millions of years and significant evidence exists that plants and soil biology have co-evolved together for millennia.
Between mineral rich soils and the soil food web, this natural system has been able to create and provide significant plant available nutrients, certainly enough to facilitate the successful life cycle of many species. Clearly from an evolutionary context this system has been able to facilitate maximum genetic expression and the ongoing evolution of biologic species.
In the not-too-distant past, agricultural fertilization practices were based on the existence of a diversity of plant and animal byproducts, animal manures, green manures, etc. These were reintroduced to the system and combined with the appropriate biologic populations, resulting in the decomposition of these organic material inputs and their conversion into plant-available nutrients.
An overview of traditional farming practices provides substantial evidence that farming has been occurring for at least 10,000 years. Why, with such a long history of symbiotic interactions between biologic species, are we now witnessing the mass deterioration of arable land, and agricultural commodities containing lower nutritional value?
An interesting common question among the conventional farming community, when the topic of organics or sustainability comes up, is “how are you going to feed the world?” Well that goal certainly will not be well served by the development of shelf stable, but low nutrient-dense foods. A greater volume of low nutrient-value foods certainly does not seem like a winning approach. Supporting agricultural systems that encourage the development of sustainable systems via locally produced, nutrient-dense food is a good start.
And the same holds true for cannabis. In fact, the parallels between the production of high quality nutrient dense foods and high quality cannabis products are quite significant.
Nutrient density in crops results from balanced, mineral rich soils, and a diversity of organic materials and biologic life, these elements provide the framework to facilitate the creation of a highly functional, biologic nutrient cycling system. A highly functional soil system results in more nutrient-dense crops, which contain measurably larger quantities of different phytonutrients, vitamins, minerals, flavonoids, and terpenes as compared to a system operating at a lower level of biologic efficiency.
Benefits that have been observed from nutrient-dense crops are: more pest and disease resistance in the vegetative and fruiting stages, greater yield, more complex and intense flavors and a longer shelf life.
Ultimately advancement in any cultivation system means finding and defining limiting factors in the given system. The objective should be ensuring the maximum biologic vitality of the components of said system and its outputs. Practically speaking, in order to enable the full genetic potential of biologic species, this means identifying and working toward the removal of limiting factors. Minimizing or entirely alleviating the factors that limit maximum plant growth will undoubtedly net positive gains and must be an integral component to any sustainable cultivation strategy.
The Earth has provided us with a highly successful, multi-million-year-old biologic system, capable of providing abundant plant available nutrients on demand, a dynamic which must be integral to appropriate and intelligent systems design.
In the pursuit of sustainability, perhaps it is time to return to our roots and begin to pursue dynamics that are mutually beneficial to all forms of biologic life.
In the next article, we will take a step back from viewing sustainability through the lens of soil and plant specific cultivation methodologies, and focus on the broader context of sustainability in cultivation systems. We will look at sustainability from the context of operational efficiency, and provide a case study from a 400-light commercial indoor cannabis operation. The case study will provide evidence that, in order to achieve higher levels of sustainability, both cultivation strategies and operational efficiency must be factored into the equation. As we will see, true sustainability is created through the efficient design, incorporation, use and management of system elements, all of which can, when appropriately designed, work together to create improved efficiency for the system.
The average commercial cannabis cultivator seems to be following the modern agricultural paradigm. That model is based on questionable and, one might say, ineffective soil systems management.
In the high-yield cannabis world, amidst decades of prohibition, following the lead of the modern agricultural model has resulted in the adoption of cultural practices that go something like this: Use and destroy the soil, then dispose of it once it is rendered lifeless and useless due to repeated heavy applications of chemical fertilizers, pesticides, and other poisons.
Certainly conventional agricultural food production and the soil management systems underpinning them are faltering, evidenced by soil systems deteriorating many times faster than they are being improved. This qualifies as a failure in my book.
What will be the fate of profit margins, sustainability and medicine in the cannabis industry if we continue to follow blindly in the footsteps of chemical agriculture? Perhaps it is time to turn over a new leaf.
Well…world agricultural production accounts for about three-quarters of the soil erosion worldwide. This steep decline in arable soil is occurring during a time when the world’s demand for food is rapidly increasing. It is estimated that the world will need to grow 50% more food by 2050, and it is important to note that, the total volume of food necessary, remains relative to the nutrient density of the food.
Time for a radical solution, and cannabis can lead the way.
As the cannabis industry continues to grow, now more than ever we have the opportunity, and I believe the responsibility, to cultivate in ecologically mindful ways, improve the end product and it’s positive impacts, increase both short-term and long-term profits, decrease or eliminate waste and lower the carbon footprint of cannabis cultivation operations.
Most importantly, we have the opportunity to fund, implement and lead the way in research and development of sustainable, medical, phytonutrient-dense crop production methodologies.
Only by implementing more rigorous scientific methods to cannabis cultivation can we hope to provide truly meaningful improvements in and contributions to the fields of agriculture, science, medicine and human health.
While dumpsters of potting soil continue to roll off to the landfill, complex health and human science and the cultivators truly engaged in science will continue to provide meaningful data regarding plant compounds and what factors influence the best outcome for the desired end product.
I am willing to bet that what is best will not be coming from the business models employing antiquated, wasteful and destructive cultivation strategies, and that in due time these models will fade into distant memories.
This is the first in a series of articles, in which we will explore topics related to the pursuit of high yield, phytonutrient-dense “high brix” cannabis production.
The next article will provide a historical and geologic context to the cannabis plant, as viewed from the scope of soil biology and the progression of ecosystems and soil types, and how maximized genetic expression, through maximized soil and plant health influence the production of high quality cannabis.
The CannaGrow Conference & Expo, held in San Diego on May 7th and 8th, educated attendees on the science of cannabis cultivation. The conference brought subject matter experts from around the country to discuss cannabis breeding and genetics, soil science and cultivation facility design.
Discussions at the conference delved deep into the science behind growing while providing some expert advice. Drew Plebani, chief executive officer of Commercial Cultivator, Inc., gave a comprehensive review of soil ecology and how understanding soil fertility is crucial to successfully growing consistent cannabis. “Soil fertility is measured by laboratories in terms of soil minerals, plant-available nutrients, percent of organic materials, pH levels and most importantly the balance of the soil’s chemical makeup,” says Plebani. “There is no silver bullet in soil ecology; increasing your soil fertility comes down to understanding the composition of soil with analytical testing.” Plebani went on to add that soil systems for cannabis need to be slightly fungal-dominant in developing an endomycorrhizal system, which is optimal for cannabis plant growth.
Tom Lauerman, colloquially known as Farmer Tom and founder of Farmer Tom Organics, kicked off the conference with an introduction to cultivation techniques. Lauerman also delved into his experience working with federal agencies in conducting the first ever health hazard evaluation (HHE) for cannabis with the National Institute for Occupational Safety and Health (NIOSH). Through the HHE program, NIOSH responds to requests for evaluations of workplace health hazards, which are then enforced by the Occupational Safety & Health Administration (OSHA). Lauerman worked with those federal agencies, allowing them to tour his cultivation facilities to perform an HHE for cannabis processing worker safety. “I was honored to introduce those federal agencies to cannabis and I think this is a great step toward normalizing cannabis by getting the federal government involved on the ground level,” says Lauerman. Through the presentation, Lauerman emphasized the importance of working with NIOSH and OSHA to show federal agencies how the cannabis production industry emerged from the black market, branding itself with a sense of legitimacy.
Adam Jacques, award-winning cultivator and owner of Grower’s Guild Gardens, discussed his success in breeding CBD-dominant strains and producing customized whole-plant extractions for specific patients’ needs. “I find higher percentages of CBD in plants harvested slightly earlier than you would for a high-THC strain,” says Jacques. “Using closed-loop carbon dioxide extraction equipment, we can use multiple strains to homogenize an oil dialed in for each patient’s specific needs.” As a huge proponent of the Entourage Effect, Jacques stressed the importance of full plant extraction using fractionation with carbon dioxide. He also stressed the importance of analytical testing at every step during processing.
Zacariah Hildenbrand, Ph.D., chief scientific officer at C4 Laboratories, provided the 30,000-foot view of the science behind compounds in cannabis, their interactions and his research. With the help of their DEA license, he started the C4 Cannabinomics Collaborative, where they are working with Dr. Kevin Schug at the University of Texas-Arlington to screen various cannabis strains to discover new molecules and characterize their structure. “Secondarily, we are using gene expression profiles and analysis to understand the human physiological response and the mechanism through which they elicit that response,” says Hildenbrand. “As this research evolves, we should look to epigenetics and understanding how genes are expressed.” His collaborative effort uses Shimadzu’s Vacuum Ultraviolet Spectroscopy (VUV), and they use the only VUV instrument in an academic laboratory in the United States. “Pharmaceuticals are supposed to be a targeted therapy and that is where we need to go with cannabis,” says Hildenbrand. Him and his team at C4 Laboratories want to work on the discovery of new terpenes and analyze their potential benefits, which could be significant research for cannabis medicine.
Other important topics at the conference included facility design and optimization regarding efficient technologies such as LED lighting and integrated pest management.
In the second part of this series, I speak with Alex Cooley, vice president of Solstice, to find out what particular solutions growers can use to increase efficiency. Last month, I introduced the challenge of growing cannabis more sustainably. To recap, I raised the issue of sustainability as an economic, social and environmental problem and referenced recent pesticide issues in Colorado and carbon footprint estimates of growing cannabis.
“Switching to outdoors or greenhouse will always be more sustainable than indoor, but depending on the type of facility, energy efficiency and specifically lighting should be at top of mind,” says Cooley. “Just looking at your bottom line, it is cheaper to use energy efficient lighting sources such as plasma or LED lighting, which will reduce your need for air conditioning and your overall energy consumption.”
Looking into sustainable technologies is one of the quicker ways to improve your overall efficiency. “We are big believers in VRF [variable refrigerant flow] HVAC systems because it is one of the most energy efficient ways to cool a large space in the world,” adds Cooley. “Use a smart water filtration system that gets away from wasting water by catching condensate off AC and dehumidifiers, filtering and then reusing that water.”
Utilizing your waste streams is another relatively simple and cost effective practice to grow cannabis sustainably. “Our soil and biomass goes through a composting company, we recapture any of our waste fertilizer and runoff for reuse,” says Cooley. “We try to use post-consumer or fully recyclable packaging to reduce what would go into the waste streams.”
So some of the low hanging fruit to improve your bottom line and overall sustainability, according to Alex Cooley, include things like reusing materials, composting, increasing energy efficiency and saving water. These are some of the easily implementable standard operating procedures that directly address inefficiency in your operation.
In the next part of this series, I will discuss Terra Tech’s approach to sustainable cultivation, which utilizes the “Dutch hydroponic greenhouse model” on a large scale growing produce such as thyme and basil, but are now taking their technologies and expertise to the cannabis industry. I will also discuss the benefits of using a third party certification, Clean Green Certified, to not only help grow cannabis more ecofriendly, but also market your final product as such. Stay tuned for more in Sustainability of Cultivation in 2016, Part III.