Most growers out there are aware that the active compounds in marijuana, ∆9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are not present in cannabis plants. Instead, the compounds found in dried flower that produces the beneficial effects of cannabis are tetrahydrocannabinol acid (THCA) and cannabidiolic acid (CBDA).
Taking a quick step back, both THCA and CBDA are created in the plant by converting cannabigerolic acid (CBGA) into them. And because some of this conversion from CBGA to THCA and CBDA continues to occur after your harvest, ensuring optimal drying and curing conditions is essential for the highest potency possible.
Both CBDA and THCA are not active in the human body in that form, and that is why we heat cannabis to convert CBDA to CBD and THCA to THC. This process of burning or vaping weed causes what is called decarboxylation.
It’s usually shortened to “decarb,” but the meaning is the same: the conversion or either THCA to THC or CBDA to CBD. While this conversion occurs naturally, called oxidation, due to light, temperature, and the presence of oxygen, it is significantly sped up at higher temperatures when decarboxylation occurs.
This information is valuable to understand so that the importance of curing cannabis can be appreciated. We want to produce the best weed possible without causing any unnecessary harm to the plant.
Why is Curing Cannabis Important?
Drying and curing are important to ensure the cannabis is safe and pleasant to consume and at the highest potency.
Some of the conversion process described above still occurs after harvest, and optimal drying and curing are needed, so this process can fully complete.
Curing also influences other compounds. Curing breaks down chlorophyll, which, if not dealt with, can lead to hay- or grass-like smoking experience. This chemical process requires light, air, and water so that bacteria can perform the process of breaking down chlorophyll and other unwanted compounds.
The curing process also impacts how the cannabis burns, and the experience of smoking the dried flower. Consumers want a smooth smoke with white ash, qualities that are considered to result from the drying and curing process.
What is Curing Cannabis Exactly?
Drying and curing are post-harvesting processes, meaning they begin after you’ve cut down and trimmed your plants. Drying generally describes the process of removing moisture on the outside of the bud, while curing is used for controlling the water content of the entire bud, both inside and outside.
The purpose is to prevent future degradation of phytocannabinoids and terpenes and to enhance the smoking experience. Plus, it ensures you don’t smoke your entire stash right away!
Drying is necessary for proper handling and storage of cannabis, with the goal of avoiding any more degradation than is unavoidable. The goal is to ensure mold cannot grow, and this is generally why the legal cannabis industry will strive for moisture content aim for 5-10%.
This allows for consumer safety under normal storage conditions for longer periods of time. The average home grower may want to dry cannabis to a slightly higher level, depending on how you like your weed and how long the supply will have to last.
Do not air dry cannabis directly on or near the ground, raise it up as much as you can. Overdrying directly damages the trichomes (the kief producing components), resulting in lost potency, so do not overdry.
Drying rooms should be well ventilated and dark. Bud can be dried between 16°−30°C for and humidity at 45-55% for a day or up to two weeks.
Bud can be dried while still on the branch, hanging upside down, or after removal so that no further trimming is required. The drying process can be sped up if you use an oven or other means, but this is generally not advised for the average home grower.
It should be noted that the degradation of terpenes can occur in temperatures as low as 21°C. The optimal temperature must balance the need for higher temperatures to get the job done while preserving as many terpenes as possible. This is why some sources suggest a temperature more along the lines of 16-21°C.
Moisture content can be assessed by measuring the weight of the cannabis after drying compared to the starting weight. Roughly 70% of the weight of your pre-dried bud is from water. If you kept the bud on the branches, a good indicator of readiness is when these branches are brittle. Drying is generally considered complete when the weed has a relative humidity level of 55%-65%.
The curing of weed is not essential, but it has numerous benefits for the overall experience of smoking the bud. Curing enhances the bouquet, flavor, and texture of your dried flower.
When done correctly, curing does not lower the potency of cannabis by decarbing THC or CBD. The following step-by-step instructions will ensure you understand how to cure your cannabis for a great final product.
- Finish removing any excess plant material
- Place the buds in airtight containers
- Write the date on each container
- Ensure your buds are gently packed, not being squeezed or damaged
- Containers should have a relative humidity of 62% if optimal
- Place the containers in a cool, dry, and dark place
- You can check the bud after the first few hours to see if an immediate difference is noted when compressing the bud
- Generally, you want to open the container 2-3 times a day, at least six hours apart, to release moisture and provide oxygen for bacteria.
- After the initial week, containers can be opened less frequently, once or twice a week
- Cure cannabis in containers for at least a few weeks, but up to six months
- Ideally, the buds are relatively sponge-like when finished
- Monitoring and tracking this process can be a simple a small journal with dates and product-quality assessments in the form of a few words
Concluding Thoughts on Curing Cannabis
This guide to curing cannabis has described the critical scientific topics to understand so that all growers can understand why it is so important to cure your weed the right way.
Following the steps here will help ensure your cannabis curing produces buds that are dry enough to be safe but also produce an enjoyable consumption experience. Beyond that, this cannabis in good storage conditions can last for many months or even years, although potency will decrease slowly over time due to oxidation.