The cultivation of cannabis can be a tough gig. Like many indoor agricultural products, the process is highly specialized. But medical cannabis also presents its own unique challenges. It takes great skill and care to properly manage the lifecycle of a cannabis plant, and that's essential for safe and effective treatment. Of course, at Sira, we know how it’s done. As a medical cannabis patient, you may still be curious about how your purchases are produced.
At every stage of growth – whether the early stages of propagation, the vegetative stage of growth, or the generative stage (“flowering” or “bloom”) prior to harvest– the growing mix plays a pivotal role.
Soil-based mixes are generally the most common growing mix used for indoor cannabis cultivation, but soilless and hydroponic growing methods are becoming a more popular and accessible option for commercial and hobbyist growers alike. Whether you’re growing in a traditional soil-based potting mix, a soilless mix composed of sphagnum peat and/or coco coir, or using an entirely hydroponic system, each method offers its own benefits and shortcomings. For example, soil can come pre-fertilized (eliminating the need for added nutrients), but artificial extended-release fertilizer (such as Miracle Gro) should be avoided as excess fertilizer buildup can negatively affect the taste of your final product. Soilless media or hydroponic systems that use mineral-based, water-soluble nutrients allow for quicker nutrient uptake which in turn can increase yields and hasten growth but this requires the grower to be attentive and focused on the needs of the plant.
No matter which medium is used, the plants’ containers should provide good drainage first and foremost. The ideal pH level of the growing medium differs for each: a PH range that falls between 6 and 7 when using a soil-based mix is ideal, while in soilless mixes and hydroponic systems a pH level of 5.5 to 6.5is generally regarded as ideal. When using a hydroponic system, the pH levels of the nutrient solution must be checked regularly as any changes will need to be corrected quickly to avoid detrimental effects to the plant. Similarly, if growing in soil or a soilless medium, you should monitor the pH of the substrate (soil/growing mix) using a reliable testing method. Getting this right is crucial for avoiding nutrient lockout, which can prevent the plants from absorbing the nutrients they need.
Plants are hungry. The primary nutrients (or macronutrients) needed are simple: nitrogen, phosphorus, and potassium. But cannabis also requires several micronutrients in varying degrees – these include calcium, magnesium, and iron. Generally speaking, if you’re using a pre-fertilized growing mix then your bases should be covered. Otherwise, specially designed fertilizers are available in water-soluble powder or concentrated liquid formats, each suitable for a specific stage of growth after being mixed with water at various recommended rates.
The water itself is better off if filtered. In some locations, water that is perfectly safe for human consumption can harm plants as well as important microbes within the soil that form an important relationship with the root structure of your crop. The most important thing to remember, even with pure, filtered water, is not to overdo it.
Lights, exhaust fans, circulating fans, ventilation, and pH test kits are the basic necessities for ensuring a good harvest. Light quality is arguably the most important environmental factor; grow lights should be chosen wisely from several options, including the industry-standard HID (high intensity discharge), fluorescent fixtures, LED (light emitting diode), and induction lamps. The size and power requirements of each piece of equipment will depend on the size, conditions, and overall needs of the grower and their grow space.
A 24-hour timer and adjustable thermostat allow the average hobbyist grower to adequately control climate but, things become more complex when scaling up to a commercial cultivation operation. Custom control software can monitor and communicate with numerous pieces of equipment to regulate environmental conditions automatically to keep hundreds of plants living in harmony at all times.
There are several variables to keep in mind here, from the amount of light the plants get to proper airflow, temperature, and humidity.
The rule of thumb is to start with a cool, dry area with a steady stream of fresh air – usually achieved by placing a filtered exhaust fan and a fresh air inlet at opposite sides of the growing space – this will allow stale air within the grow to be replaced regularly with fresh air rich in carbon dioxide – a critical component necessary for plant photosynthesis. A light breeze, created by a circulating fan, is good for strengthening the plants’ stems and keeping mold and pests at bay. But timing is everything: The ideal light/dark cycle will consistently give the plants 16-to-20 hours of light per 24-hour period when in vegetative growth, which is then reduced to 12 hours of light followed by 12 hours of darkness when they’re ready to begin the important process of forming buds.
Finally, in terms of temperature, cannabis plants seem most comfortable in a range of 70-to-85 degrees F during the lit (day) period, and 58-to-70 F during the dark (night) period. Whether the temperature is higher or lower on this scale depends on the strain of cannabis. Some lighting systems do generate more heat than others – but conditions also depend on the space. Which finally leads us to…
For a cannabis garden to make the grade (need inspiration?), the area’s size and capacity for cooling and heating are key concerns. The space should be “light-tight,” too; if any light leaks in during dark periods, the plants may produce male flowers instead of female.
Ultimately, the best facilities offer the capacity to cultivate, harvest, dry, trim, process, and package all products on-site. This means added amenities such as a commercial-grade kitchen for making edibles and a high-tech lab for producing oils and concentrates. Above all, cleanliness is critical, so facilities should always be fitted with easy-to-clean surfaces.
Rest assured that professional cannabis growers have the time, energy, and experience needed to follow this process to the letter. Of course, it also doesn’t hurt to avoid the hassle of navigating the many laws on home growing. If you still have questions, though, feel free to ask – different dispensaries use slightly varied techniques and equipment to yield the best results.