Growing Cannabis: Where to Start

February 14, 2017   

As the political climate surrounding the legalization and production of Marijuana shifts, so too, must the industry of agriculture. At this stage in the political environment, many experienced cannabis growers have gained their decades of experience experimenting in underground operations. Because of the individuality and different methods of experienced growers, there is much debate over a few techniques for growing.  The following is an overview of generally agreed upon principles when starting your own growing operation.

Outdoor versus Indoor Growing:

Because of Marijuana’s stigmatized history, contemporary growers have often grown in and adapted to their indoor environments, using technology and experimentation to find success. Nevertheless, for centuries in our country, farmers depended largely on hemp production and prophesized the economical uses of the crop in America’s future. Like all other plants and animals, Cannabis has genetically developed to grow in response to its environment. This is the major reason growers must try to recreate and improve upon environmental factors when growing indoors. Growers manipulate light cycles to promote plant health and growth. Recreating air flow and wind helps to strengthen the plants’ root system, improve air quality and resist disease and pests more effectively.

Luckily, cannabis is a pretty adaptable plant. Cannabis can be grown and cultivated indoors, outdoors and hydroponically both indoors and in greenhouses. Each method has its unique characteristics and benefits. Many underground growers forced indoors, avoided the issues of an uncontrolled environment, simulating what was beneficial and never having to adapt to the elements of nature. Benefits of a well-controlled indoor grow operation are uniformity in plants, protection from destructive weather and the option of cleaner methods of growing, like hydroponics. Many claim that indoor grow operations produce superior buds specifically because of the ability to control the environment and nutrient distribution.

While growing outdoors might introduce some conflicts between you and Mother Nature, there are a few benefits some growers find to choosing outdoor growing methods. Space is certainly a major benefit. Many growers also agree that growing outdoors is more economical in that it doesn’t require lighting and other grow room costs. But, if you prepare and build a healthy and successful grow room, though it might be more demanding, your harvest quality can be much more catered. Nevertheless, a Washington State certified lab compared almost 3,000 samples of cannabis and their research found that outdoor-grown cannabis was at least 1% higher in THC levels than indoor-grown plants. Cannabinoids and terpenes, which increase a plants flavor and potency, respond best in sunlight.

 To achieve successful harvests knowing the growth stages of cannabis is essential.

Stages of Growth in a Cannabis Plant:

Germination Getting your seeds started

VegetationThe longest and arguably most important stage. Before flowering begins, you must determine the sex of your plants- it is recommend that growers buy feminized seeds to begin. The most common way to tell male and female plants apart before pollination is by observing two indicators of each sex. Male plants will form a cluster of pollen sacs or false buds between leaf nodes, and females will develop two white hair-like shoots in a V-shape at the leaf nodes. Unless you are growing to produce seeds, it is highly recommended that you identify and kill the male plants as soon as you can, before the pollen sacs open and contaminate the female plants. If allowed, this type of cross-pollination produces minimal, weak buds, seedy plants and is a big waste of time and resources.

Pre-Flowering– Stage of growth before flowering, which entails a vegetative growth spurt

Flowering– The stage at which flowers or buds form and develop into mature plants

Trimming, Drying and Curing– The final stage of maintaining potency and developing flavor, preparing flowers of high quality. Hang buds to dry at around 65-75 degrees Fahrenheit with humidity around 50%.

There are a set of vital decisions when developing your process that you must consider in advance. Some debates arise between growers when facing the choice of growing methods and personal experiences.

Seedlings and Seed Quality

It all begins with a seed- preferably, a high quality and potentially costly seed. Seed grown plants are generally stronger and more disease and pest-resistant. There is a debate within the community regarding feminized seeds. Some growers prefer buying already feminized seeds, while others refuse to use feminized seeds because of their potential to turn to hermaphrodites and not produce well. There are a numbers of ways to propagate a seed. The following are a couple recommended methods.

 The first method, which requires minimal work, is to directly plant a seed, no further down than an inch into soil, and lightly spray or water from the bottom in a tray. If you have spent a shiny penny on your seeds, as you should, this might be a little more risky depending on your watering. You do not want to over-water your seeds creating rot. A preferred method is using either a light layer of saran wrap or wet paper towels to hold in the moisture without over-wetting the seeds. Many growers recommend using filtered or bottled water to avoid the Chlorine in municipal water. You want your germinating seeds to maintain moisture and a temperature of around 68-77 degrees Fahrenheit. Germination should occur within a few days.

Once your taproot emerges, you must transplant the seed into your growing medium. Plant the seed root-end down. Try to avoid handling the seed and root as much as possible, as irreparable damage can easily occur during this fragile state. Also, after transplanting try to water lightly with a spray bottle. Water when the top inch of soil feels dry to maintain moisture, but again, try to avoid drowning the root. Beginning with a high-quality seed with successful genetics is arguably the most important primary step.

Growing Medium

As a versatile plant, Cannabis can be successfully grown in a field, a greenhouse, high tunnel or indoor grow room of virtually any size. Labor and energy needs vary from medium to medium, and each growing environment has both benefits and drawbacks to an operation.

If using soil, it is best to plant in a light mixture of potting soil and use an N-P-K fertilizer specifically as directed on the product you choose. Nitrogen is most important in the vegetative stage, as it is what feeds the foliage, which provides energy for the plant’s growth. Yellowing leaves usually signify a nitrogen deficiency or overwatering. Nitrogen should be applied most in the vegetative stage and lowered to allow Phosphorus to be dominant in the following stage. Phosphorus is most important during the flowering stage for producing healthy, non-leafy seeds and buds. Potassium has a major role in the building and transfer of sugars and absorption of water and nutrients throughout the plant, and it should be maintained at the same level during the entire life cycle of the plant. Many growers recommend using a 12-12-12 ratio or a 20-20-20 ratio, adding supplements of nitrogen during vegetation development and phosphorus during flowering. Try to avoid extended or slow-release nutrients, as they can confuse the plant in its flowering stage.

pH of soil and water should be tested and considered through the plant’s life cycle. You want to maintain a pH level of 5.5-6.5 for the soil and a pH level of 6.0 for your water source.

Hydroponics, a Cleaner Green

There are multiple benefits growers notice when using hydroponic systems. Not only do they avoid the messiness of bringing soil into their controlled environment, but they find a system can be left for several days without attention. Such a system can be used indoors in a grow room or in a greenhouse. NFT trays or Dutch Buckets are recommended for your hydroponic needs. Growing hydroponically versus in soil can yield more produce per square foot of growing room, drastically cut labor costs and improve efficiency.

 With labor being a major cost in agricultural operations, many operations and farms suffer from the dependency on and cost of employees. Hydroponic systems are also cleaner and help eliminate an enormous potential for disease and critters that are found in soil, and if in a greenhouse, hydroponic systems like NFT channels can slash energy costs to a small fraction of the energy costs of indoor grow rooms. More importantly, these shallow streams of water and nutrients provide an abundant supply of oxygen to the plant roots and produce a higher yield and high-quality product.

One concern that has the potential to arise with hydroponics systems is the idea that if one plant gets a pest, disease or rot, then essentially every plant has the same problem, as they are all connected and sharing a water and food source. Many experienced hydroponic growers would respond to this concern by explaining that if the cleanliness of your building is a priority in your operation, you will not run into this problem.

Lighting and Light Deprivation

Natural or artificial growing lights are an important issue to consider when growing cannabis. Understanding the light cycle of Cannabis is vital to its successful production.  Lighting initiates photosynthesis. The combination of light and nutrients, like nitrogen, are the basis for the plant’s food and creating a strong and sturdy structure.

When you put your germinated seedlings under lights, a minimum of 18 hours and a maximum of 24 hours of light are necessary. Some growers give their plants a few hours of rest to avoid drying soil overnight. Other growers maintain the importance of 24 hours of light in the vegetative stage. Keep your plant from touching or getting too close to the light and burning its leaves.

As your plant reaches the pre-flowering stage, it will experience a growth spurt, often referred to as “The Stretch.” This pre-flowering stage lasts about 10-14 days. Depending on your growing techniques, you will decide what signifies that your plant is ready to flower. Some go by height, with a general measurement of 4 ft. indicating that it is flowering time. If you use the Sea of Green method of growing shorter, bent plants, your indicator might just be cognition of the weeks that have passed and your desired plant size.

The next phase of the light cycle is the flowering stage which can last from 6-22 weeks, depending on your environment and space. Many people decide to produce an 8-week blooming plant. During the flowering stage, to promote the development of flowers, you will change your light timer to a 12 hours on, 12 hours off cycle. This is because while photosynthesis promoted by the leaves is helping the plant to grow and form in its vegetative stage, darkness, or light deprivation, is what promotes the flowering stage. In fact, in an indoor grow room one important practice is making sure you have no light contamination during the cycles of light deprivation. Just before harvesting and during curing, it is essential to maintain light deprivation as light degrades trichomes, the crystal-like hairs that hold THC. 

Air Flow

Proper ventilation and air flow are critical to the health of your grow room and plants. Use fans and ventilation to move stale air and avoid mildew, disease, pests and to help strengthen your plants root system. A light breeze maintains a moderate temperature under lights and heat mats, and mimics the outdoor breeze that pushes the plant around, bending and strengthening the roots and branches.


Spacing largely depends upon whether you are growing indoors or outdoors. Outdoor growing allows for less spatial limits and without containers, the plant’s root system has as much space as it needs to develop freely. Many recommend four feet per plant for outdoor planting. For indoor growing, growers agree that you want to fit as many plants under each light without having them touching one another, to avoid issues that may arise due to poor ventilation, air flow, humidity and pests.

Harvesting Cannabis

Harvesting cannabis correctly, is a consequential part of creating a high-quality final product. The recommended harvest time is when about 2/3 of the stigmas, or the white hair-like shoots, begin to turn orange. This sweet spot does not last long and plants should be harvested before the stigmas turn from orange to brown, losing a level of potency and crystals.

 After cutting your branches, carefully trim the leaves on the stem and around the buds with a pair of small scissors, and hang the branches to dry or place on a drying rack. When the thinner parts of the branches are easily snapped, but the thicker parts maintain some flexibility, you should trim your buds and put them into air tight mason jars, in complete darkness, to begin curing. Keep an eye on your buds and let in a little air sparingly if there is too much moisture to avoid moldy cannabis buds. A successful curing can mean a world of difference in the aroma, potency, flavor and type of high a grower, customer or patient might experience. 

When beginning to cultivate cannabis, get to know the plant’s life cycle and become aware of pivotal changes in life stages. After understanding key elements to growing cannabis, the first major task is to set up a healthy space for your plants. Through experimenting with one’s own crop, growers will find methods that work best for them. These basics should help beginners gain a primary understanding of cultivating cannabis.

Contributed by Amanda Williams