Knowing when to harvest cannabis may be one of the most important aspects of the entire marijuana growing process. Especially for those folks that are new to growing weed.

If you harvest marijuana too early it can result in a lower potency of pot than what could have been achieved if it were allowed to grow a little longer. And chopping your crops too late could cause the potency of the THC to start to degrade. Yikes!

So finding that ideal window in which to harvest weed plants is crucial for executing an optimally-potent crop of cannabis.

Here’s The Dope Regarding When To Harvest Cannabis

The Timeframe

When growing weed indoors, most Indica and Indica-dominant cannabis strains are ready to harvest at around 7-9 weeks after the beginning of the bloom cycle. But Sativa and Sativa-dominant marijuana strains can take as long as 10 weeks or more to finish their flowering phase.

Using a calendar to help keep track of your garden’s progress is a valuable tool to gauge when to harvest weed. However, marking a date as to when to harvest cannabis is not the best way to determine when your plants are ready to chop.

The best way to tell when to harvest marijuana is by using your eyes.

The Signs

The true tell of when to harvest cannabis is in the glandular trichomes. You know, the sugary goodness that sticks to your fingers and gets you stoned. Yeah, those things. They are the absolute best way to determine when to chop your pot.

trichome head
Glandular trichome head

They’re like the miniature crystal balls of growing weed, and observing them closely in the last few weeks of the flowering cycle will help you decide when to harvest.

Monitoring the color of the weed leaf is another way to help you regulate when to harvest marijuana. If your cannabis crops are healthy, the plant leaves will have a lush, green color for the majority of their lifespan. But as the marijuana plant draws closer to the end of its lifecycle the weed leaf will begin to lose its green color, it will then turn yellow, and eventually shrivel up and fall off.

weed leaf
Weed leaf color

The aroma can be a telling factor as to when to harvest weed as well. This is because the fragrance of the buds changes throughout the entire ripening cycle. However, until you have a few grows under your belt, monitoring the weed leaf color and glandular trichomes are your best bets for establishing when to harvest cannabis.

The Trichome Tell

It’s important to point out that you’re going to need some form of magnifying device to actually see what’s going on inside the heads of the glandular trichomes, such as a jeweler’s loupe or a miniature microscope that magnifies the object [weed] you’re looking at by a minimum of 30 times (60x and up is the best bet).

And just what is it that we’re looking for now that we can magnify our eyes? We’re taking a look at the acids that secrete into the heads of the glandular trichomes. More specifically, the color of the secreted acids. Or the lack thereof.

The Colors

During the early stages of the flowering phase, the acids inside the head of a glandular trichome will appear to be clear in terms of coloration. This is due to the fact that the acids that are being emitted into the trichomes are still developing and maturing along with the floral clusters of the plant’s buds.

clear trichomes
Clear trichomes

As the cannabis buds begin to reach the end of their ripening phase, the acids inside the glandular trichomes arrive at their peak of production and start to change color. The production of cannabinoid acids is considered to have almost reached their peak when their coloration changes from a clear tone to a cloudy, milky-white color inside the trichome head.


Harvesting marijuana at this stage of cannabinoid acid production would be considered as being a bit too early and result in an end product with lesser potency than the plant is capable of producing. That’s where exercising great patience comes into play when growing cannabis.

Cloudy-white trichomes
Cloudy-white trichomes

The optimal time to harvest cannabis is when the acids inside almost half (40-50%) of the trichome heads have changed from a cloudy-white tone to an amber or brownish color. Harvesting at this time will result in cannabinoid acids that have reached their most favorable level of production and potency. Be sure to note that there’s only an approximate 8 to 14-day window of opportunity at this stage of cannabinoid acid production before they mature fully and start to degrade.

amber trichomes
Amber trichomes

Allowing cannabinoid acids to fully develop would mean all or most of the acids inside the trichome heads would have a brownish, amber color. Harvesting at this stage of acid development would result in the most potent end product, but the timeframe to harvest is short before the acids actually begin to deteriorate and decay. Thus making the finished buds less potent.

The Deduction

When you learn to associate the changing colors of the weed leaf with the progression of cannabinoid acid production it will become much easier for you to determine when to harvest cannabis.

As long as you have the right tools; proper direction; and plenty of patience; you’re sure to succeed as a cannabis gardener. The more you grow, the more you’ll know.

Previous articleWeed Tab Pot Quiz: Test Your Weeds TV Show Skills
Next articleColorado Marijuana Legalization Has Big Impact on Economy
Neo has been writing for the cannabis industry since 2008 and is an active gardener with two sticky, green thumbs. He would love to see the prohibition of cannabis brought to a close, and is doing his best to make it a reality by staying involved on a grass roots level. When it comes to partaking in a puff or two of the sticky stuff, Neo is partial to just about anything Indica, especially OGs.