Every time I harvest cannabis, I make a conscious choice; do I want to harvest a heady, clean buzz that borders on psychedelic, or a descent into the depths of my couch, with my eyelids growing heavier by the second, and the room slowly falling dark? Harvest timing (among other things) has an enormous effect on the properties of any strain you’re growing. At it’s extremes, it can make even the best Sativas act like an Indicas or vice versa.
It’s About the Trichomes
At the simplest level (it’s still very complicated), it comes down to trichome development. To understand this we need to understand what a trichome is and why we should care.
Trichomes are small glandular hairs found on Cannabis plants, which probably first developed as a protection mechanism for our favorite plant. If you’ve ever looked at a poster of a big juicy bud while waiting in your favorite dispensary, you’ve certainly seen trichomes. They function to keep away insects just like the way capsaicin in hot peppers exists to stop animals from eating them. The irony is that these same compounds such as THC, CBD, and terpenes, are the ones we’re interested in. As the plants develop, the trichomes start out clear, progressing through cloudy into amber. Each phase has very different qualities.
Earlier Cannabis Harvest
When I talk about an early harvest, it means most of the trichomes are cloudy. When trichomes are cloudy but still whitish, their mix of chemistry provides an extremely clean sort of psychedelic experience. On a haze, it allows my consumers to toke as much as they desire, boosting the psychedelic qualities while simultaneously bringing “couch lock” down to almost zero. It’s very energetic and energizing. You won’t become sedated, and the effect can mimic narcotics or other compounds. Many may doubt me, but I’ve absolutely hallucinated on weed harvested in this way.
Later Cannabis Harvest
I’ve taken those same strains and harvested later (some trichomes are amber and some are cloudy) and produced something reminiscent of a hybrid. Lemon Haze is a favorite for this since later harvesting boosts its flavor. Feelings of couchlock are reintroduced, with higher levels of CBD forming in the amber trichomes as they oxidize and degrade. Harvest timing is a tool I use to customize different strains. There are drawbacks for either earlier or later harvest.
Earlier vs Later Cannabis Harvest
The more time I allow for my plants to flower, the easier it is to pack on more weight. It’s in my best interest to make my buds heavy, compact, and potent, for both my bottom line and my consumers experience. No one wants fluffy buds but I’ll talk about what I look for when purchasing fresh flower later. It’s all a balancing act, where a day or two can tip the scales. The longer I wait, the more amber trichomes I have, the more THC breaks down and forms CBD (and other compounds), and eventually flavor suffers. However, if I’m too early those same compounds have yet to peak. In some cases, this may be what I want.
Harvesting Time for Medicinal Cannabis
When growing strains for medicinal purposes, I usually harvest late. They wouldn’t be considered recreational by most consumers due to their highly sedative effects, which is why demand is generally lower (less demand means less profitability). Most have massive CBD contents and very little THC, which was aided by a late harvest. Cancer patients don’t care about getting high, they just want to be able to eat and sleep. This accomplishes that goal (in conjunction with good breeding).
On the flip side, the last time I grew Trainwreck I harvested a portion early for a more recreational feel and it blew my mind. I sacrificed a small amount of weight, which would have gained back by letting it continue to grow. The earlier harvest created a product on another level of high. The trichomes were mostly milky, and lent to an incredibly clean buzz. Early harvests also cause diminished terpenes such as Myrcene which are notorious for couchlock, helping drive a mind-altering experience. For some, it’s a bit too strong and may not be a pleasant experience so choose wisely.
The Typical Harvest Time
When in doubt, a normal harvest where 25% of the trichomes are amber and the rest are milky is fine. It’s (fairly) standard and will still give you amazing products. For those of us in the industry wanting to tweak strains a bit further, timing is one of many tools available. Next time you’re curious, grab a magnifying glass and take a look for yourself.
About the Author
Joey d’Artagnan holds a multiple degrees from top institutions including a bachelors in chemistry. He also has comprehensive education in botany and horticulture, and has spent over 10 years consulting extensively for both the craft beer and cannabis industries. His experience includes both indoor and outdoor production-scale grows, encompassing soil, hydroponic, and aeroponic methods. Additionally, Joey has developed cloning, breeding, and edible programs for a variety of top-tier cannabis and hemp operations spanning both coasts. Joey currently resides in Boulder, Colorado.
Thanks for this piece Joey, and for providing a great blog! I’ve been growing cannabis at home for a few years and have learned a great deal–enough to understand how much I really DON’T know, so I greatly appreciate generous people like you who share so much knowledge! I found your piece while trying to gain insight into a problem I’m having with my current crop.
I don’t know if you give advice to people who write you here, but I thought…worth a shot! I have a grow of Super Silver Haze that was doing just beautifully up until weeks 5 – 6 of flowering, when they suffered heat stress in their basement grow tent during a heat wave. Trichome growth stopped at that time, at 20-30% of the production I’d expect. By week 7, existing pistils had mostly browned and curled, trichomes were mostly cloudy and some were goin pale amber. Based on the cloudy trichomes I started to contemplate harvesting early. SSH normally has a long 10-11 week flowering period but I thought maybe heat stress could impact that. Then over the next 3 weeks, many new white pistils emerged throughout. They’re still mostly white as I near the end of the 10th week of flowering. Narrow “Foxtail” calyx growth also began to emerge from the tops of the flowers along with the robust wave of new pistils (this is what tipped me off to the heat stress). They continue growing, with new longer rounded-tip leaves growing out at the tops of the flowers. Under the microscope, it still doesn’t appear that trichomes resumed much growth (a little recently I think). Trichome density is disappointingly thin still. Most visible trichomes are cloudy. Some are frosty and some a little dried up or stubby or crumb-like). Amber trichome count is very inconsistent from flower to flower. Some buds have none. Others range from 5-50% amber. With the new leaf, calyx and pistil growth happening, I’m trying to figure out if I should let them continue to develop on the plants, maybe through week 11, and hope for more trichomes to develop, or if I’m going to risk losing the heady type of effect I’m growing this strain for.
Any thoughts? Sorry this is such a long note. It’s a complicated scenario I think and I’ve found nothing online that provides helpful guidance. Thanks again for the great content!
Chris