|Posted on March 6, 2019 at 8:20 AM|
Harvesting Medical Cannabis for Maximum Strength and Quality
Harvest is a crucial moment in a medical cannabis plant’s life, but the details on how to go about it are not always cut and dry. How do you know when the plasnt is mature enough to pick? What steps can you take to ensure that your bud is of the highest quality and has a smooth flavourful smoke? I will do my best to answer these questions and more as we delve deep into cannabis harvesting preparations and techniques.
Cannabis Harvest: Timing Is Everything
When it comes to harvesting, timing is everything. You want to cut down your plants as the flowers reach their peak resin and trichome production. If you harvest too early, your buds will lack THC and other essential cannabinoids. If you harvest too late, the resin containing the cannabinoids will begin to degrade.
There are countless strains and phenotypes available, each with flowering times unique unto itself. Environmental factors can also play a role how long a plant needs to flower before harvest. Plants grown indoors tend to have their flowers mature faster compared to the same plants grown outside. So, how does one determine the ideal time to harvest when there are so many factors at play?
Medical Marijuana flowers/buds take on average eight to 12 weeks to mature. Again, this varies depending on the strain. When buying seed or clones, check for traits such as flowering length when buying seeds or clones for a rough estimate on how long your plants may take. Once you’ve neared that estimated time frame, there are a couple relatively accurate methods you can use to visually inspect your flowers for maturity. The first would be to look at the pistols, the long hairs that grow on the surface of the bud. As the flower approaches maturity and peak resin production, these hairs will turn from white to an orange/brown color. Now, this isn’t always the case (I’ve personally sampled some incredible bud that was harvested with only white hairs), but it is a good general indicator.
An even more effective way of determining flower maturing is to examine the trichomes. These are the resin glands that contain cannabis’s psychoactive ingredients, and they look like white fuzz covering and contained within the bud. Take an up-close look at the trichomes using a magnifying glass, microscope, or a macro lens on a DSLR camera. (I personally recommend the later as it allows you to save a record of your plants’ progress, helping you make comparisons in future grows and allowing you to compare notes with fellow gardeners.) The glands look like balls at the end of stalks. On immature plants, the resin is almost clear. On mature plants, it is milky and opaque. If the resin has turned an amber color, however, it is already beginning to degrade.
(More on when to harvest cannabis? How do I know when my plants are ready for harvesting?_
Flushing for Flavor
Flushing is a process one does prior to harvest. It helps to remove all built up salts and minerals from your growing medium, as well as forces your plants to use up their sugar reserves. Using up the remaining sugars ensures a smooth, flavourful smoke with a fantastic scent profile.
To properly flush plants, you need to give them only pH-balanced water for the last one to two weeks of the flower cycle (you can use the estimated flowering time of your plants to calculate when to start the flush). If you are growing hydroponically, simply use only pH-balanced water in your reservoir. However, change your reservoir water every day for the first three days to get all the salts out of your system. Plants grown in soil or soilless potting mixes should be flushed with double the usual amount of pH-balanced water for three days and then only use water. Plants begin to show signs of nitrogen deficiency (the older leave yellow and die off) when they are flushed of nutrients. One trick you can use to tell if your flush is successful is to take a larger fan leaf from one of your cannabis plants, rip it in half, and taste the juices. If it tastes bitter, keep flushing. If the juices taste clean, your flush has been successful.
If you don’t have a full two weeks for flushing, there are clearing solutions available that can speed up the process.
The Final Prep
Two to three days to end of the flowering cycle, when your flushing is complete, you want to allow your growing medium to go dry. This is important for two reasons. First, it rids the plants of excess water prior to drying for a quicker dry. Second, it makes your grow room less humid. Dry air in the last few days before harvest has shown to increase resin production in many strains as the resin produced by marijuana plants was evolved to protect the flowers from the sun’s heat and UV rays.
Plant: Cut, Dry, and Cure
A few days before you plan on harvesting, start removing the larger fan leaves that haven’t fallen off on their own. This helps to remove excess water from the plants and allow for better air circulation during the drying process. This is also the time to prepare your drying room for the incoming plants. Clean it thoroughly and make sure your fans are operating. Fans are essential to circulate air, exhaust humid air out, and draw in fresh air.
Harvest first thing in the morning and do not turn on your lights. Turning on your lights causes your plants to begin drawing up sugars stored in the roots overnight. These sugars lead to harsh smoke if they are present in the buds.
Cut your plants at the base of the stalks, right above the root balls. You can hang your plants whole. If your plants are large, cut them into smaller branches for easier drying and better air flow. I personally like to hang my plants upside down to allow gravity to bring any remain juices to the bud. Keep in mind that even though your plants are cut, they are still alive until completely dry.
After five to seven days, your buds should be relatively dry. At this point, you can trim them from the branches and remove any excess, non-resinous leaves. These buds feel very dry and crisp on the outside but can still be somewhat moist in the center (this is especially true of larger ones weighing more than a couple grams). The curing process can help draw out this extra moisture. Many first-time cannabis growers make the mistake of not properly curing their flowers, leading to a harsh smoke and much of their crop lost to mold. To avoid that, place the freshly trimmed buds in freezer bags or, ideally, glass jars with rubber airtight seals. Then, open the container for 10 minutes three to four times each day for two weeks. The frequent sealing evenly distributes the moisture throughout your buds, while the unsealing lets the buds breathe and keeps that moisture from spoiling the flowers. After two weeks, the buds should be properly cured and are ready to be enjoyed now or stored safely for the long term.
Harvesting is such a critical moment for your cannabis plants. Careful record taking, keen observance of trichome development, and a patient drying and curing process are the keys to a successful and potent cannabis harvest.
Written by Gibson Lannister