The medical cannabis industry is still in its infancy stage with many theories and methods available on how to cultivate it. But if growers want to be competitive and grow their business, it’s important to adopt the best practices of a well-established horticultural methodology. If you combine that with newly generated crop knowledge and leading technology, you've got a successful medical cannabis business at hand.
Having a good understanding of the basics of medical cannabis cultivation can help growers maximize yield, quality and profits.
Since growing medical-grade cannabis in an open field is nearly impossible, and indoor facilities cost up to 50% more than greenhouses (and go hand-in-hand with extremely high operational costs), cannabis greenhouses are clearly the way to go.
But even when you know that cannabis greenhouses are the right choice, you need to select the optimal structure for your local climate. For hotter areas, you will need a lighter structure with good rooftop ventilation. For colder climates, you may need a glasshouse. Choosing the right structure is critical since it will affect both your quality and your ROI.
When growing medical cannabis, regular crop protection products are out of the question. Therefore, climate control is critical not only to create optimal conditions for plant development, but also because it serves as your pest management system. A combination of structure components, supported by sensors and a smart controller, control and maintain the correct humidity and temperature to avoid mites, mildew and other fungal infections.
Achieving the highest possible return on your medical cannabis project requires the ability to maximize crop cycles and optimize every square meter of greenhouse space. Therefore, it’s critical to manipulate day length and control flowering. The inevitable challenge you’ll face when utilizing light deprivation systems is maintaining full control of your greenhouse environment, in terms of both temperature and humidity, during blackouts. To buttress your light dep screens, you’ll need smart solutions for preventing the sun from entering through ventilation components or via your fan and pad system. Automation based on radiation sensors is also crucial to maintain precision, since maximizing photosynthesis without compromising flower induction is the key to high productivity.
The two production stages of medical cannabis require very different irrigation protocols. The first stage, propagation, needs light droplets, high humidity and a system that supports small containers. When the new plants are mature enough to be transferred to the production area, they require a system that can uniformly irrigate large containers with high frequency and zero added humidity.
Our special PC CNL drippers make a noticeable difference in the production area. They are not only pressure regulated but also non-drainage, so they eliminate draining effects that disrupt uniformity and allow several irrigation cycles per day with perfect water distribution across the entire farm. Together with special manifolds and drop guides, the container is evenly watered and root development is optimal.
While customized premixed cannabis nutrients are available, using them for a commercial operation is an economic burden. Fortunately, medical cannabis is less complicated to fertilize than popular opinion proposes. The 18 nutrients that medical cannabis needs to thrive significantly overlap with the fertigation needs of many other crops; the key is in your ability to adjust flexibly the ratios based on development stage and environment.
The ideal dosing system will use six to eight channels: three for N-P-K, one for calcium and magnesium, one for a microelement blend, and the last to control pH. Too much more and you’ll experience complexity and over specification, bogging down your operation. Your system should support a tank mix for the final solution to give you uniform, consistent results.
The Netaflex medical cannabis fertigation system is an exceptionally precise, state-of-the-art open-tank dosing system, designed to place medical cannabis plant nutrition directly into the palm of the grower’s hand.
Medical cannabis is not like growing corn or tomatoes. As a grower, you are held accountable for quality and required by the pharmaceutical industry to ensure that your production process is documented and traceable. Medical cannabis fertigation, irrigation and plant protection specs need to be available on demand for any given plant.
With Netafim’s digital farming and monitoring tools, not only do you have a better handle on what’s going on with your crop at any given moment, but traceability is built-in.
While drainage is often an overlooked component of the agricultural process for any greenhouse crop, managing drainage is actually a great way to grow better crops with fewer resources. Since growing in soilless media requires irrigating with drainage volume of 30% or more, reusing drainage can save you 30-40% on your fertilizer expenses and water use. Additionally, the drainage volume measurement is a great way to monitor and control irrigation. Measuring nutrient content in your drainage can tell you a lot about your plant uptake and how to tweak your plant nutrition plan.
That’s true for any crop, but medical cannabis drainage carries legal obligations. Because of its narcotic nature, drainage can’t always be conveniently flushed into a river. Legislation demands 100% water recycling for some facilities.
Drainage reuse, whether optional or mandatory, requires the right water treatment system. You can avoid spreading of pathogens with water treatment systems like the Netafim NUF system, and control the nutrient content in drainage with our ec/Ph monitoring and our nutrient systems.
Want to know more about drainage management?
Without expert know-how, even superior technology will deliver only mediocre results. But when it comes to medical cannabis, it’s complicated to find “the right expert”. Medical cannabis has only recently become accepted as a standard crop, so well-vetted, global knowledge relating to professional cultivation is naturally limited. On the other extreme, any “expert” with years of experience growing medical cannabis is likely lacking foundations in modern horticulture and agricultural technology.
Netafim has been doing large scale, hi-tech greenhouse projects for over 50 years, and has accumulated a significant track record in all crops including solutions for growing medical cannabis worldwide.
Medical cannabis plants need 18 nutritional elements to grow well. Do I need 18 fertilizer dosing channels?
No. All crops need the similar elements in different ratios. Having good control over the quantities and ratio is important, but for medical cannabis, six to eight dosing channels will suffice. You’ll need three for N-P-K, one for calcium and magnesium, one for micro elements, and the last for acid to control pH. An 18-channel dosing system isn’t “the more, the merrier.” Too many dosing channels is a drain on your resources in terms of both time and finances, to accomplish something you could do more simply.
How can I avoid humidity in my medical cannabis greenhouse, while reducing the risk of mildew and other diseases?
First, use a ventilated structure. Choose one with good roof top ventilation and add active ventilation if needed. For humid places, It is recommended to add a dehumidifier on top. Our greenhouse experts can help you select the right combination of equipment according to your local humidity conditions.
How many outlets do I need per growing container?
Medical cannabis is typically grown in large containers, so the recommended number of water outlets per container is four. In smaller containers two can be sufficient. An effective design uses a PC CNL non-drainage dripper with a spider manifold to split the flow to four outlets, while ensuring proper water distribution within the container.
Can I grow organic medical cannabis with drip irrigation and fertigation?
Yes, but since organic fertilizers have more suspended solids, if you’re going organic, choose a different emitter recommended specifically for organic fertilizer usage, like our UNIRAM CNL with the add-on manifold. This way, your drippers will work with no risk of clogging even with a heavy load of suspended solids. Additional flushing of the driplines is recommended as well.