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The 3-Legged Stool of Successful Grow Operations: Climate, Cultivation & Genetics – Part 1

By Chris Wrenn, Phil Gibson
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Ideal cannabis profits come from high demand/high selling prices and low production costs. The spread between those two, or margin, can determine the life or death of your business. We want to share this series of articles so that your next investment can be highly successful and high margin out-of-the-box.

Regardless of the grow method (soil, coco, rockwool, hydro or aero), every plant performs best in its own ideal environmental conditions. Experienced growers gained success through hard work, and just that, experience. Many have tried more advanced grow technologies, but shied away due to early trial failures or the complexity of maintaining chemistry across a grow facility. The wonderful thing now is that precision sensors and software controls eliminate the risk to robust healthy plants and harvest success. Growers are now able to both manage production while performing research in line with their operations.

We have learned a great deal working with our grow partners over the last 6 years. Every grow facility and location are different due to local weather, business environment and scale. This series of articles and guide, authored by our expert, Christopher Wrenn, will include recommendations of the most successful approaches we have seen here in North America and all over the world.

A 4-Layer fully aeroponic flower room using movable racking systems

Building top-quality cultivation facilities is no simple task. Cultivators are also looking for new help as they shift from older soil or media approaches to more efficient grow methods. One powerful method is aeroponics, which is very good at growing any type of plant in air in a sterile environment, with labor, nutrient and water savings.

Where possible, we will share key vendors that support healthy grow operations and (since it is World Series Time), customer examples that are knocking it out of the park. In today’s competitive business environment, it is critical to do what we can to increase profitability and survival in the face of steep headwinds. We want you to crush it and be “the last man standing.”

So, let’s get to it.

Climate: Environmental Control

We begin with a critical leg in your environment. The process of photosynthesis is more than just light, plant and moisture. We want to do more than just grow plants. We want to grow highly profitable plants. That means we have to accelerate photosynthesis so we are growing faster, bigger and more potent than our competitors.

The Vapor Pressure Deficit (VPD) is the amount of “drying power” available in the air surrounding your plants. This is a useful way to understand the amount of moisture your atmosphere can remove from your plants as they digest carbon dioxide and aspirate water and oxygen into the air around your plants. A higher vapor deficit is a good thing for growth; It is also a measurement of how much nutrient you can uptake into the plant roots and convert into size and potency in the canopy. We recommend that you have resources in your grow rooms to maintain your environment to within 5% of both your humidity and temperature targets for ideal results.

Onyx Agronomics is a Tier 3 indoor cultivator in the State of Washington. This is the canopy in one of their 8 flower rooms.

In our Top Quality Cultivation Facility white paper, we review environmental settings for temperature and humidity for mother, clone/veg and flower rooms for day and night light cycles from early cuttings through to end of harvest flush. Day temperatures can be up to 20% higher than night temperatures for example.

Cooling

Managing temperature may seem straight-forward but the heat generated by LED lights, HPS lights or the sun will vary across rooms, time exposure and with the distance of the light source from the plants. Measurement sensors should be distributed across rooms to monitor and trigger temperature resources.

Humidification/Dehumidification

This is a topic that can be underappreciated by cultivators. It is important to slowly transition humidity as you move plants from cuttings to clones, to veg and to flower. Beginning in a very humid stage to motivate root start, humidity will be stepped down from an opening near 90% down to an arid 50% in your end of flush flower rooms. We detail the transitions in 5% increments in the white paper.

The 4-Layer aeroponic flower room with movable racking systems from the side with a tall human for scale. One can do a lot with 30′ ceilings.

Relative Humidity (RH) and the related VPD are the key metrics to accelerating growth throughout the stages. Not sizing dehumidifiers correctly is one of the most common mistakes our grow partners learn about as they move to full production. In the first phase of turning cuttings from healthy mothers into rooted clones, hitting your target VPD to motivate root growth is the number one success factor. This will require the addition of humidity into your clone room. It is also typical to require raise the humidity of your flower rooms when you transition clone/veg plants from the high humidity clone/veg room into an initially dry flower room, otherwise the plants may go into shock as a result of the dramatic change.

As flowering begins, if humidity remains high, and the VPD is below target, the plants will not be moving nutrients and transpiring moisture. We have seen lowering the humidity from 70% in a flower room down to 50%, results in a yield increase from 50 grams to 90 grams of dry trim bud per plant, so a smooth transition can both accelerate growth and have a big impact on your margins and profitability.

Plants in aeroponics can truly have explosive growth. This means that they will also transpire moisture at an accelerated rate. Fast automated growth in aeroponics means increased humidity output. Sizing these critical systems for humidification/dehumidification are a critical part of the design process.

Airflow

Fans combined with your cooling/heating/humidity/dehu systems need to mix the air in a room to break the boundary layer at the leaf surface for transpiration. As we covered, VPD is critical to growth success. A dry surface motivates the plants to transpire moisture. We recommend flow rates across the canopy in a 0.5-1.5 meter/second rate to align to your genetics and where you are in the flowering process.

A raw facility before it gets outfitted.

Airflow and flowering means rich beautiful aromas are generated. Every facility has to consider odor control. If you are in a populated area, you will have ordinances and neighbors to satisfy. The best way to do this is to minimize the amount of air that exits a facility. This is also the cheapest approach.

Sterile HEPA filters and scrubbing systems clean air of pathogens and odor but they also need to circulate and “condition” air to the correct temperature and humidity levels before it can be recirculated into a room. Oftentimes, this is a good place to also recapture humidity and reinject it into your pure water cleaning systems.

Key vendors to talk to about sizing air treatment systems are SURNA, Quest, Desert Aire and AGS. Each of these vendors have specialties and tend to be superior partners in different regions of the world. We would be happy to introduce you to excellent support resources for air management systems.

To download the complete guide and get to the beef quickly, please request the complete white paper Top Quality Cultivation Facilities here.

Click here to see Part 2 where we discuss water quality and management.

Keeping Your Environment Clean: Preventative Measures Against Contamination

By Jeff Scheir
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For years we have heard about and sometimes experienced, white powdery mildew when growing cannabis. It is a problem we can see, and we have numerous ways to combat it. But now more and more states are introducing regulatory testing on our harvests and they are looking for harmful substances like Escherichia coli., Aspergillis Fumigatus, Aspergillis terreus, …  just to name a few. Mycotoxins, mold and bacteria can render a harvest unusable and even unsellable- and you can’t see these problems with the naked eye. How much would it cost you to have to throw away an entire crop?

You bring in equipment to control the humidity. You treat the soil and create just the right amount of light to grow a superior product. You secure and protect the growing, harvesting, drying and production areas of your facility. You do everything you can to secure a superior yield… but do you?

Many of the organisms that can hurt our harvest are being multiplied, concentrated and introduced to the plants by the very equipment we use to control the growing environment. This happens inherently in HVAC equipment.

Your air conditioning equipment cools the air circulating around your harvest in a process that pulls moisture from the air and creates a perfect breeding ground in the wet cooling coil for growth of many of the organisms that can destroy your yield. As these organisms multiply and concentrate in the HVAC system, they then spew out into the very environment you are trying to protect at concentrated levels far greater than outside air. In effect, you are inoculating the very plants you need to keep safe from these toxins if you want to sell your product.

The cannabis industry is starting to take a page from the healthcare and food safety industries who have discovered the best way to mitigate these dangers is the installation of a proper UVC solution inside their air conditioning equipment.

Why? How does UVC help? What is UVC?

What is Ultraviolet?

Ultraviolet (UV) light is one form of electromagnetic energy produced naturally by the sun. UV is a spectrum of light just below the visible light and it is split into four distinct spectral areas – Vacuum UV or UVV (100 to 200 nm), UVC (200 to 280 nm), UVB (280 to 315 nm) and UVA (315 to 400 nm). UVA & UVB have been used in the industry to help promote growth of cannabis.

What is UVC (Ultraviolet C)?

The entire UV spectrum can kill or inactivate many microorganism species, preventing them from replicating. UVC energy at 253.7 nanometers provides the most germicidal effect. The application of UVC energy to inactivate microorganisms is also known as Germicidal Irradiation or UVGI.

UVC exposure inactivates microbial organisms such as mold, bacteria and viruses by altering the structure and the molecular bonds of their DNA (deoxyribonucleic acid). DNA is a “blue print” these organisms use to develop, function and reproduce. By destroying the organism’s ability to reproduce, it becomes harmless since it cannot colonize. After UVC exposure, the organism dies off leaving no offspring, and the population of the microorganism diminishes rapidly.

Ultraviolet germicidal lamps provide a much more powerful and concentrated effect of ultraviolet energy than can be found naturally. Germicidal UV provides a highly effective method of destroying microorganisms.

To better understand how Steril-Aire UVC works, it is important to understand the recommended design. Directed at a cooling coil and drain pan, UVC energy destroys surface biofilm, a gluey matrix of microorganisms that grows in the presence of moisture. Biofilm is prevalent in HVAC systems and leads to a host of indoor air quality (IAQ) and HVAC operational problems. UVC also destroys airborne viruses and bacteria that circulate through an HVAC system and feed out onto the crop. HVAC cooling coils are the largest reservoir and amplification device for microorganisms in any facility.

For the most effective microbial control, UV germicidal Emitters are installed on the supply side of the system, downstream from the cooling coil and above the drain pan. This location provides more effective biofilm and microbial control than in-duct UVC installations. By irradiating the contaminants at the source – the cooling coils and drain pans – UVC delivers simultaneous cleaning of surface microorganisms as well as destruction of airborne microorganisms and mycotoxins. Steril-Aire patented this installation configuration in 1998.

The recirculating air in HVAC systems create redundancy in exposing microorganisms and mycotoxins to UVC, ensuring multiple passes so the light energy is effective against large quantities of airborne mycotoxins and cleaning the air your plants live by.

Where are these mycotoxins coming from?

Aspergillus favors environments with ample oxygen and moisture. Most pre-harvest strategies to prevent these mycotoxins involve chemical treatment and are therefore not ideal for the cannabis industry.

Despite the lack of cannabis protocols and guidelines for reducing mycotoxin contamination, there are some basic practices that can be utilized from other agricultural groups that will help avoid the production of aflatoxins and ochratoxins.

When guidelines are applied correctly to the cannabis industry, the threat of aflatoxin and ochratoxin contamination can be significantly reduced. The place to start is a clean air environment.

Design to win

The design of indoor grow rooms for cannabis is critical to the control of airborne fungal spores and although most existing greenhouses allow for the ingress of fungal spores, experience has shown that they can be retrofitted with air filters, fans, and UVC systems to make them relatively free of these spores. Proper designs have shown clearly that:

  1. Prevention via air and surface disinfection using germicidal UVC is much better than chemical spot treatment on the surface of plants
  2. High levels of air changes per hour enhance UVC system performance in reducing airborne spores
  3. Cooling coil inner surfaces are a hidden reservoir of spores, a fertile breeding ground and constitute an ecosystem for a wide variety of molds. Continuous UVC surface decontamination of all coils should be the first system to be installed in greenhouses to reduce mildew outbreaks.

UVC can virtually eliminate airborne contaminants

Steril-Aire graphic 4

Steril-Aire was the first and is the market leader in using UVC light to eliminate mold and spores to ensure your product will not be ruined or test positive.

  1. Mold and spores grow in your air handler and are present in air entering your HVAC system.
  2. Steril-Aire UVC system installs quickly and easily in your existing system.
  3. The Steril-Aire UVC system destroys up to 99.999% of mold/spores.
  4. Plants are less likely to be affected by mold…with a low cost and no down time solution.

It’s time to protect your harvest before it gets sick. It’s time to be confident your yield will not test positive for the contaminants that will render it unusable. It’s time to win the testing battle. It’s time for a proper UVC solution to be incorporated throughout your facilities.

Biros' Blog

Sustainability of Cultivation in 2016, Part II

By Aaron G. Biros
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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.

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The growers at Solstice put their plants under a trellis net to increase yield.

Alex Cooley is the vice president of Solstice, a cultivation and processing business based in Washington. Solstice is at the forefront of the industry for innovating in energy, water and raw materials efficiency. I sat down with Cooley to discuss exactly what you can do to grow cannabis sustainably.

“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.”

solsticegrowop_feb
Indoor cultivator facilities use high powered lights that give off heat, requiring an efficient air cooling system like VRF HVAC.

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.

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The tops of plants are beginning to flower in this Solstice indoor facility.

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.