Determining Ideal Harvest Timing

Determining when your plants are ready to harvest is one of the most vital decisions throughout your grow operation, with definitive effects on the quality and quantity of your crop. In order to determine when the bud is ready to be harvested, you'll be assessing the maturity of the trichomes on your bud, looking for the density or cloudiness of their structures, along with the degree of amber you can see. 

It's important to understand how trichomes interact with your body, in order to determine when the trichomes are ready for harvest.

Time of harvest affects both the quality and the quantity of your bud.

• Quality through the chemical structure of the cannabinoids at the time of harvest. 

• Quantity based on the time your plants are given to grow.

Harvest time is determined by the cloudiness and degree of amber within the trichomes, and is measured based on the percentage of trichomes that appear cloudy.

Light Distribution

If the plant is receiving even lighting throughout the canopy you will be able to harvest the whole plant at its peak time.  

If lower areas of the plant are not getting enough light then they will need to be harvested separately, due to underdeveloped (clear) trichomes. The top of the plant and outer areas receive the most light, so they develop more quickly, and will allow you to harvest them earlier. Ideally your plants have even lighting throughout the canopy, so you can harvest the whole plant at one time.

Measurement Tools

The primary tool you'll use to judge the quality of the buds is a magnifying glass, or jewelers loupe, so you can examine the trichomes closely to determine the density of amber, and the clarity of the trichomes: little hair-like structures covering your buds. The human eye is not even capable of detecting certain types of trichomes, so it's important to use the proper equipment to get an optimal reading. 

Additional Indicators

In addition to the indicators visible through a magnifying glass, there will be other visual indicators throughout the plants that will also help you know when to harvest.

These other indicators are:

• Plant's leaves fading in color to a lesser green, yellow or even purple towards the end of the flowering stage

• Top of the plant will has firm, dense flowers (top buds)

• Bud colors are bright and vibrant

• Clear distinct smell with complex aromas due to terpenes

3 Main Trichome Characteristics

First, what are trichomes? Trichomes are small crystal-like resin glands that line the flowers and leaves of the plant to protect it from outside influences. They are particularly concentrated around the flowers of the plant, as protecting reproductive functions is vital to re-propagation and subsequent evolution. Trichomes are also bitter and acidic to animals attempting to eat them, so it makes the flowers less likely to be consumed.

The biggest contributory factor to the density of trichomes and subsequent potency of today's marijuana is human domestication and development. Most weed in the late 60s-early 70s had approximately 7% THC- but as farming became profitable, and potent marijuana became more valuable, even today's mids range from 18-23%, with higher-end genetics topping 30%. 

Another feature your trichomes may represent indicating harvest readiness is hints of amber within the trichomes. Some consider this to be the key feature that indicates the ideal time for harvest. The importance of amber is dependent on strain, more significant to Indica readiness than Sativa, which is more dependent on the degree of cloudiness.

Strain Type Determines Ideal Harvest Time

Different strains need different amounts of time to harvest, as some strains grow and mature more quickly than others. 

Sativas

Sativas are faster growing, taller plants with the longest flower cycle, generally needing 10-12 weeks before they are ready to harvest. The key indicator for Sativas is the degree of cloudiness within their trichomes. 

The goal of cultivating a Sativa plant is to produce a psychoactive, “heady” high with THC triggering CB1 receptors within your brain and nervous system. 

As trichomes are given more time to develop THC, more contributory to a psychoactive high, slowly transitions into CBN, which contributes to tamer pain-relieving and sleepy highs. So the ideal time to harvest a Sativa is a lower percentage of cloudiness than you would want for a heavy indica. 

There are competing theories on the degree of cloudiness that is ideal for harvesting, feel free to do your research to determine the ideal target. We recommend aiming for a 10-20% balance of cloudy vs. clear trichomes for Sativa plants, with a hint of amber. That way the THC has released to its maximum potential without too much transition to CBN. 

Indicas

Indicas are stockier, slower growing plants with the shortest flower cycle, most taking only 7-8 weeks in flower. While cloudiness is still important, the development of amber is the key indicator of readiness for most Indicas. 

The goal of cultivating an Indica plant is to produce a palliative, pain relieving and sleepier high, with CBN and CBD triggering CB2 receptors across your immune system. 

By allowing the trichomes to have a thicker, cloudier development, THC is still at relatively high levels, but you allow for the production of CBN and CBD to create the anti-inflammatory and relaxing effect you're hoping for. 

We recommend looking for significant levels of amber within your trichomes, and a 30-35% cloudy vs. clear distribution. You're also aiming to see development of pronounced colors, frostiness, and aroma. 

Hybrids

The ideal harvest timing for hybrids is largely dependent on the distribution between sativa and indica of your strain, along with the type of high you're aiming for. 

The same rules apply, harvest earlier in the cycle if you're aiming for a psychoactive high, and later in the cycle if you're looking for a soothing, pain relieving high. And meet somewhere in the middle if you're looking for a combination.

We advise allowing a significant degree of amber to develop, while aiming your trichome density towards the goal for your high, between the 10% (Sativa) and 30% (Indica) parameters.