THC will begin to break down/deteriorate around 80 to 85 degrees F. At around 115 to 122 degrees F resin glands will begin to melt and some cannabinoids will begin to vaporize. Roughly around 125 degrees F to 156 degrees F the resin glands will become fully liquid, more cannabis flavors and aromas (terpenes) are released, as more different cannabis compounds begin to vaporize. Around 170 degrees F to 212 degrees F the resin will boil and small amounts of THC will begin to vaporize. Significant amounts of THC (around 5%-6%) begin to be released around 365 degrees F.
You NEVER want to use heat to dry a crop or even for a quick dry to sample your crop. To begin with a fair degree of THC is in a non-psychoactive form in freshly, or recently, harvested cannabis so at best when smoked it will not give you a true representation of the quality it will have if given a proper long slow dry followed by a long slow cure, which is needed to allow the non-psychoactive THC to become psychoactive. When you use heat to dry your crop or sample you will lose more THC, both psychoactive and non-psychoactive THC, so what you smoke will be even less representative of what a properly dried and cured harvest would be.
Do not dry using heat, not even for samples. If you want a sample to smoke use normal room temperature air to dry it by moving it over/through your sample bud or buds. Use something like forceps or hemostats or a vice-grip to clip to a bit of stem and put it in front of a fan and be patient and let it dry. You can use a blow dryer, not on a heat setting, to blow air over/through your sample bud or buds. Once clipped to something or held to something that will hold them in place if its summer and your A/C is running you can set your sample bud or buds on an A/C vent. Use moving air but not hot, or even warm air or you will lose THC.
Drying Marijuana After Harvest
You probably don't want to smoke marijuana that is harsh and bad tasting. If you do not take time to dry the bud, you will not get the best possible smell and taste your crop is capable of producing.
Proper drying and curing will also ensure maximum potency of the marijuana you have grown. Marijuana is not potent just after harvest. Some of the THC is in a non-psychoactive acidic form. Drying marijuana the right way will convert the non-psychoactive acidic compounds into psychoactive THC.
The area where the drying is done should be dark. Light and high temperatures (higher than about 80 degrees) will cause THC to break down into less desirable chemicals, this will lower the potency of the finished product.
A good way to dry the crop is to
hang the buds upside-down by the stem, from some string or wire. The drying marijuana must have some circulation blowing over it at all times. A gentle breeze that circulates over all the plants is necessary.
A fan or two will circulate air within the drying room. Fans will aid in drying the plants evenly, and reducing the chances of mold. If mold starts and is allowed to grow, it might ruin all of your crop. Mold looks like white fuzz and has an odor that is unpleasant.
You will have to keep the temperature and humidity within a certain range for optimal results. Conditions should remain constantly somewhere within the following ranges, temperature should be between 65-75 degrees F, relative humidity should be between 45%-55%.
At temperatures lower than 65 degrees, drying time will be lengthened. At temperatures higher than 75 degrees, the heat will cause the outer portion of the bud to dry quicker than the inner part, and the taste will suffer.
At humidity levels lower than 45%, the marijuana will dry too fast and the taste will suffer. At humidity levels higher than 55%, the marijuana will take a long time to dry, and it will be prone to mold.
Keep a hygrometer and a thermometer in the drying area, close to the plants. A hygrometer will allow you to keep an eye on the relative humidity level in the room and a thermometer will display the temperature. Some
hygrometers
have built in thermometers so you can measure the temperature and humidity together.
Depending on the time of year and your location, a heater or an air conditioner may be necessary to adjust the temperature. To control humidity, a
dehumidifier can lower humidity and a
humidifier can be used to raise humidity. There are warm mist humidifiers and cool mist humidifiers.
A warm mist humidifier will raise the temperature while a cool mist humidifier will not affect the temperature. There are also humidifiers that allow you to switch between warm or cool mist. If you are going to purchase a humidifier for this purpose, take your climate into consideration and buy an appropriate humidifier.
Warm mist models will actually heat the water and release warm humidity. Cool mist water isn't cooled, it just means that water is not heated. In most cases a cool mist will work best. To be safe you can get a humidifier that lets you switch between warm and cool mist.
Curing Marijuana
It will take at least a week or two to dry the crop with temperatures between 65-75 degrees F and relative humidity between 45%-55%. You will know when the marijuana is dry if the stems snap or break (rather than fold) when they are bent. Try smoking a small bud (1/2 gram or less) in a joint to be sure it is dry enough.
At this time, small buds will be dry enough to smoke. But larger buds should be cured (slow dried) to ensure that the marijuana is as potent and tasty as possible. If necessary, you can set aside buds that are less than 1/2 gram for smoking, while larger buds cure.
The cure lasts a week or two. The aim of what you are doing is evenly finishing the slow dry process, so that mold will not grow when the buds are stored long term. Also, by the end of the cure, any remaining inactive THC will be converted to active THC (that increases potency).
To cure the crop, you will need one or more containers made out of glass or plastic. Some people say plastic can impart a taste to the marijuana. Personally, plastic containers that some types of roll your own tobacco are sold in, have no negative effect on the taste.
Containers that have a rubber seal work best, but any type of container with a tight fitting lid will do. One quart
canning jars do a very good job if you are curing a few pounds or less. They have a rubber seal and hold 2 or more ounces of marijuana per one quart jar.
When curing quantities in excess of a few pounds, large (over 40 quarts) plastic
storage boxes
are recommended. They are not air tight, but will do the job when smaller air tight containers are not practical.
Gently place your marijuana in the containers (cut buds to size if the are too big to fit in the container) and put the top on. Store the containers in a dark area where the temperature is between 50-65 degrees and the humidity is between 40%-60%.
You will have to open the containers for a few minutes to allow moisture to escape by fanning with your hand. If any moisture builds up on the inside of the cap on your container, wipe it off. Do this preferably 2-6 times daily, at regular 4-12 hour intervals.
You should also re-arrange the buds by giving them a quarter-turn once a day. This will ensure that different parts of the buds are exposed to the air in the container. Keep up this routine for 7-10 days. When properly dried, marijuana will burn evenly when smoked in a joint (if stems are removed).
The taste will be as good as it can be, and the THC will have reached a point where it is ready to be ingested or stored. You can keep any marijuana that will be consumed within a few months (1 year maximum) in the same containers used for curing, without having to keep opening them to release moisture.
If the marijuana is to be stored for more than a few months, you can use a
vacuum sealer (designed for storing food) to seal the marijuana in an airtight environment. If stored in a dark area that is between 40-55 degrees F, the marijuana in vacuum sealed plastic will remain potent for up to 5 years.
Dry marijuana can be stored in a frost-free freezer, but some of the THC on the outer part of the buds may be damaged when frozen. A refrigerator is in the right temperature range but they tend to be humid (unless you can control the humidity).
If stored in an area of high humidity for months or years, even vacuum sealed marijuana can eventually become as humid as the surrounding air. This will necessitate drying it again before smoking. But, unless mold develops, humidity itself will not degrade the THC or make the marijuana any less potent.
Light will degrade some of the THC, so dark containers can be used for storage. If you place the marijuana in a see through container, it will have to be located in a dark area that is not exposed to light or high temperatures.
Always make sure to properly dry your marijuana prior to storage, if you grow your own or if the stuff you have is very moist. And remember that to preserve marijuana potency at a maximum level, keep any exposure to air, heat, and light at a minimum.