Following the propagation and vegetation stages of cannabis cultivation, plants will enter the flowering stage, where growers can see the literal fruits of their labor.
At this stage, cultivators need to remain diligent and detail-oriented as they grow their plants to maturity, while maintaining records of their development and working with labs to analyze cannabinoid and terpene profiles. All cultivars and concentrates require specific considerations and cultivation techniques, so keep in mind what your end goal is and act accordingly.
1. Eliminate lower material and branches, as well as fan leaves and large leaves.
As explained in stages 1 (propagation) and 2 (vegetation), you need to remove lower vegetation that will not receive direct light, whether artificial or natural sunlight. This process can be performed between weeks one and two of the flowering stage.
2. Only utilize the best plants.
If you propagate more plants than you need and vegetate only the best tissue cultures, clones, or seedlings, you will be able to select the very best vegetating plants to transfer to flowering. This tip sounds obvious, but the many growers I have heard from who employ this practice unanimously agree that it’s better to have more choices than fewer. While this requires more space and costs more to cultivate plants that you may not use in the end, the additional labor, time, and expenses are worth growing the best possible plants.
3. Apply products preventively.
Weeks one and two of flowering are typically the last chances to apply any beneficial preventive fungicides, Bacillus thuringiensis (BT), neem oil, or other products that can aid in preventing development of budworms, powdery mildew, grey mold, and other issues. It’s important to check the product manufacturers’ recommendations for use, as well as state and local laws and regulations for approved products and use.
4. Brace or support plants early.
It is best to stake or support plants before the roots spread in order to minimize any possibility of root damage. Whether you employ netting, stakes, or another method, it is best to place supports before the plants begin to flower.
5. Ensure proper airflow between plants.
Properly space all plants far enough apart to ensure maximum airflow between them. This helps prevent hot spots from lights and the proliferation of powdery mildew, while promoting carbon dioxide and oxygen distribution. Additionally, implementing circulation fans can help properly move the air between the plants, both during daylight/lights on, as well as nighttime to prevent elevated humidity environments.
6. Utilize the proper light spectrum.
As previously mentioned, the flowering stage has its own light spectrum requirements. These required spectrums are typically elevated levels of red spectrum and reduced levels of blue spectrum, compared to those preferred in vegetative growth. There are lights that allow a grower to fine-tune the two spectrums to accommodate the specific requirements of a given cultivar. You must always experiment and see if a chosen cultivar has specific requirements that allow a grower to adjust its parameters to maximize health, growth, and flower development.
7. Perform periodic lab analysis and keep records.
Whenever possible, send multiple specimens to a lab for analysis when unsure of a new cultivar’s potential, or when attempting to fine-tune development or determine peak levels of a given cannabinoid or terpene. Keep thorough records throughout the flowering cycle and log all aspects of plant development until the end of the cycle. For example, track when the plant finished growing, the THC levels at finish, and the weight of finished product versus waste biomass.
8. Select proper genetics.
The first rule here is to only grow cultivars that are marketable. Why grow cultivars that nobody desires? Constantly do market research so you always know which products sell best and how they fit into your niche. Know your market and perfect your product for that market. There are typically multiple markets available, such as affordable, craft, and staple cultivars, and popular flavors of the week. Some flavors of the week come and go very fast, so don’t invest excessive time, effort, and resources into a flash-in-the-pan cultivar that nobody desires when you bring it to market.
9. Adjust processes based on what you are growing for.
Are you growing for bag appeal? Extracts? A specific cannabinoid or terpene? If you are ultimately going to extract the cannabis you are growing, is bag appeal really important to you? Or would you prefer a cultivar that produces more available cannabinoids on a plant or bud that are slightly fluffier and perhaps aren’t as dense as the buds destined for top-shelf flower? If you intend to extract the whole crop utilizing hydrocarbon extraction, you may choose to harvest the crop a week or so early to ensure your final extract is lighter in color than full-term buds. (These buds have mature resin glands that contain older oxidized resin glands and cannabinoids, and/or darker-colored amber pigments, etc., that can contribute to an undesirable darker-colored extract, such as budder, shatter, or wax.) Decide exactly what you are growing and why. After you determine the market you intend to accommodate, choose what to grow, how to grow, and why.