Harvest is one of the most overlooked yet critical stages in your hemp farming process. It is a tricky and difficult process, especially at scale. Here in the Hatch Valley of Southern New Mexico, we learned in real-time and applied many tried and true methods to effectively harvest our crop.
Harvest is one of the most overlooked yet critical stages in your hemp farming process. It is a tricky and difficult process, especially at scale. Not only can plants mature at different rates, but your cannabinoid levels may be different on the same plant between your apical cola and your lateral colas. You may have an area of the field more exposed to shade which can mess up the light cycle of the plant.
Down in the hot and dry climate in the Hatch Valley of Southern New Mexico, we learned how to measure the growth of our phytocannabinoid levels within the plants in order to time the harvest. Southern New Mexico Climate allows for a very long grow season, so it was a real risk to over mature our plants as far as THC percentage. "Hot" Hemp is useless and illegal waste, and the best way to avoid it is through proven genetics and constant testing.
The best way to determine when to harvest should be more pointed toward regulations and keeping your total thc percent below 0.3%. As harvest approaches, frequent testing is the best way to time your harvest to ensure your cannabinoids are maximized within legal limits. More experienced growers with familiar genetics will have better timing to ensure quality product.
Right now this formula is what most states are following in their testing labs to calculate total thc. Below is taken from the New Mexico Department of Agriculture.
Total THC = (0.877 * %THCA) + %THC
Hemp matures in about 90-120 days. The maturity of hemp depends on many factors like:
- Summer temperatures
- Climate and elevation
- Seeding dates
- Growing conditions
Harvesting hemp generally occurs at the start of October when the plants are sixteen weeks old, unless you are growing autoflower. When growing for hemp flower, you will see your flowers become ripe with the development of rich beautiful trichomes. At the same time, many feeder leaves can change color as the nutrients are pushing to feed the flower.
How to harvest hemp?
Hemp is harvested either with some version of mechanical harvester via a combine, or is hand harvested. Good harvest processes ensure hemp is immediately hung in a climate controlled environment ready to dry. Otherwise, wet plant material is usually shipped to a drying facility or goes wet into cold storage. We opted for a mechanical harvester unit in our New Mexico Hemp crop and we continue to adjust and optimize the process for larger scale harvest.
What to do when hemp reaches maturity?
When your crop begins to reach maturity, harvest should be accounted for immediately. Set up a plan to dry your hemp yourself of through a crop consultant, or local dryer. Contact your local agricultural department for resources who can help. The New Mexico Department of Agriculture has been a critical resource throughout our hemp farming process.
Drying and curing hemp:
After harvesting hemp, growers move plant material to the drying area. It can be a simple structure like a warehouse or a basketball gym ;) -yes we saw you out there doing it in 2019- or it can be an air conditioned facility.
Regardless, the drying facility should be well-ventilated, under a roof and most importantly out of the direct sunlight. It is important to set-up fans that blow continuously. Better ventilation is important. The ideal temperature for curing and drying is 60-70 degrees Fahrenheit with 60% humidity. When it comes to heat, always take it low and slow.