Once the cannabis plant is ready for harvest, its precious and delicate trichomes are in one of their most vulnerable states.
Overexposure to oxygen, light, and/or heat may degrade cannabinoids and terpenes, or activate them prematurely. Trichomes become more fragile and therefore more susceptible to breaking off the plant if mishandled under extreme conditions.
When harvesting cannabis plants, growers should implement methods of drying, trimming, and curing that reduce the amount of agitation the plant experiences in order to limit any damage to the trichome glands.
When your cannabis is ready to harvest, cut the whole plant at the base, or cut the plant into large branches. Hang your plant or cuttings upside down on a clothesline in an environment that is not overly dry or humid.
At this point, some growers begin manicuring their plants by cutting off all remaining fan leaves and some of the sugar leaves. Plants should be left hanging upside down to dry until the stems slightly snap when bent.
Avoid losing trichomes by not letting your branches hit any surfaces while hang-drying. Contact with a surface can damage the trichomes and could cause them to break off the plant. Depending on environmental conditions, the initial drying process usually takes three to seven days.
The trichome gland will experience a few changes during the drying process. The most noticeable is a loss of the extremely pungent smell. This is due to a loss of the most temperature-sensitive terpenes, or hydrocarbon compounds that produce each cultivar’s unique aroma. Studies have found that upwards of 30% of monoterpenes, or terpenes with two isoprene units — as opposed to the three isoprene units of sesquiterpenes, four isoprene units of diterpenes, and so on — produced during the flowering phase are lost in the drying process. Additionally, when cannabis is dried, terpene compounds are oxidized, and the terpene technically becomes a terpenoid.
Once the initial drying is complete, it’s time to finish trimming and manicuring your bud. Cannabis is typically trimmed to remove the excess sugar leaves that, while consumable, have a smaller concentration of trichomes than the flower and can be harsh when smoked. Sugar leaves aren’t normally discarded, however, as they are excellent for making edibles or concentrates.
Begin trimming by holding your colas by a stem and gently cutting away any sugar leaves and stems that surround the buds. This is a very delicate process that requires attention to detail. Ideally, this is done over a screen to collect any trichomes that may break off the plant. Take extreme care when handling your bud. Every moment of contact can result in trichome loss or damage. Whenever possible, hold your plants and branches by the end of the stem.
Wet trim vs. dry trim
While most cultivators trim their cannabis after drying, some prefer to trim while the plant is still wet. When cannabis is trimmed immediately after harvesting, the leaves are still full of chlorophyll, which may lead to a persistent grass-like aroma. Trimming the plant once it has lost most of its moisture is the more traditional approach.
Curing can be considered the final drying stage, allowing bacteria on the surface of the buds to break down any residual chlorophyll and ensuring the colas are neither too moist nor too dry.
This should be a gradual process, as a bud that gets too dry will degrade more easily during transportation and packaging, lose potency, and become unnecessarily harsh to smoke. On the other hand, the bud that is too wet may grow mold.
Preserving fragrance and flavor is a key concern for cannabis cultivators while curing. Overexposure to light, oxygen, and high temperatures can break down cannabinoids and terpenes, and ultimately reduce potency. Striking a delicate balance between dry and moist is the key indicator of a finely cured bud.
Growers should never rush through curing. The process often requires significant trial and error. One to two months is generally a sufficient length of time for curing, though preference and available time to cure may differ among growers. It’s important to keep the environment around your cannabis cool during the curing phase.
This curing process can be performed by placing your trimmed buds in a glass jar or Rubbermaid tote for 4-8 weeks.
During the first week or two, the containers should be opened daily to allow some fresh oxygen to replace the air in the container.
This process is called burping and is repeated until the buds have the optimal moisture content. In the last two weeks of curing the containers are opened every 2-3 days.