There are numerous techniques for determining when is the optimal time to harvest your flowers at its peak THC production. One such technique is the examination of your flower’s trichomes.
Trichomes are “are fine outgrowths or appendages on plants, algae, lichens, and certain protists.” (1)
Trichomes are “factories that produce the hundreds of known cannabinoids, terpenes, and flavonoids that make our favorite cannabis strains potent, unique, and effective.” (2)
They appear as elongated mushrooms or phallic shaped, transparent, and are sticky when touched. Separating the trichomes from the plant material (keif) is how you create hash, oils, or butters.
To examine trichomes of cannabis, you will need to magnify your vision by 60-200 times. There are a number of available tools that you can purchase to accomplish this.
Lighted Pocket Microscopes (“Dope Scopes”)
You can purchase inexpensive lighted pocket microscopes for around $5-30. They have a LED light and require a battery to power it. The illumination is quite helpful in shaded areas and provides a clearer view in general.
USB & Portable Digital Microscopes
USB & Portable Digital Microscopes typically allow you to capture photo and video content. They also allow greater magnification and closer more steady examination.
Do not purchase Jeweler Eye Loupes or a Magnifying Glass. They usually only magnify your view around 2-30 times. However if you can find one in the 60-200x range, have at it.
Once you are able to see your plant’s trichomes clearly, you can now determine when it is ripe for the picking. Trichomes start out clear and as they mature they become “milky” or translucent. At the end of flowering they will become light brown or an amber color.
The optimal time to harvest is when 70% of the trichomes have turned “milky” or translucent and less then 30% have turned light brown or AMBER.
It is important to note that this combination is for peak THC production. Harvesting early will produce a different, possibly desirable effect as well as harvesting late. Harvesting while most are trichomes are cloudy is said to produce a “heady high” and harvesting while the majority are amber is said to produce more of a “body high” or “couch-lock”. By monitoring the ratio of the two allows the horticulturist to produce different effects from the same strain of cannabis.
Terpene production is also at its peak at the 70-30 Ratio, producing a stronger aroma that is desirable among cannabis connoisseurs.
“Terpenes are common constituents of flavorings and fragrances. Terpenes, unlike cannabinoids, are responsible for the aroma of cannabis.” (3)
For more information check out the following links:
(1.) “Trichome” Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Trichome (2.) “What Are Trichomes and Why Do They Exist on Cannabis?” Patrick Bennett https://www.leafly.com/news/cannabis-101/what-are-trichomes-on-cannabis (3.) “Introduction to Terpenes” medicaljane.com https://www.medicaljane.com/category/cannabis-classroom/terpenes/#introduction-to-terpenes