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When to Harvest Marijuana | Trichomes Guide

Although a heavily trichome-coated bud isn’t necessarily a sign of a cannabis plant’s high psychoactivity, weed growers use this crucial index to determine when to chop their plants. I’ve been there, my first grow, week 9, wondering if my plant is ready for harvesting. Fortunately, most seed banks include the flowering time for their marijuana strains and it’s a good guide to keep in mind. That being said sometimes you aren’t even aware of the strain’s genetics when growing, or you end up with a new phenotype. Whatever happens during the grow setup, you should learn to check the cannabis crop yourself so you can chop when the weed is to your liking.


A small backlit magnifying glass or jeweler’s loupe will work impeccably well. They can be bought for under $ 20 at a grow shop or online, look for one with greater than 25X magnification at the minimum. By relying on this affordable tool you can completely assess the development of your bud’s trichomes.

By looking at the heads of the trichomes, a grower will observe either transparent, opaque, or amber colors. Trichome color changes depending on the strain and age of the cannabis plant. In almost all strains, the heads of glandular hairs are originally transparent in the early and middle stages of flowering. Gradationally during late flowering, they turn cloudy and opaque, this is when THC contents are at their maximum. Once they start to turn amber in color, it is a sign of THC breaking down and some see it as the time to harvest.

Some growers harvest when only half their trichomes are cloudy swearing that it is when they get the best buzz. Of course, nothing tells you better than how high you get – so chop samples at different periods to determine the optimal harvest time for your marijuana strain. Simply cut a flower or two at different stages near the estimated crop time.

By harvesting, before the trichomes are amber in color, you maximize the THC content of the cannabis plant, but the advanced quantities of THC will degrade CBD. For this reason, growers looking to maximize the CBD contents of their cannabis should harvest when most trichomes are still transparent. You’ll have about 2 to 3 weeks to tweak your harvest to your liking and establish a growing pattern for that particular strain.


3 Stages of Trichome Development.

Green ArrowsClear (transparent) Trichomes
Yellow ArrowsCloudy (opaque) Trichomes
Red ArrowsAmber Trichomes
Harvest Marijuana | Trichomes Guide

How Trichome Color Influences When to Harvest Cannabis

Some home growers prefer to chop their plants when the trichomes are mostly clear to give a more cerebral or head high. Others prefer to harvest their cannabis well after their trichomes have gone past cloudy and almost all of them have turned amber. This much later chop will give the consumer a more comforting high. This is done at the peril of the plant’s THC content, so if you want high THC numbers, try to hit the sweet spot. This coveted harvest window seems to be when most trichomes are cloudy and some are just starting to turn amber while lower buds may have some clear trichomes. Happy Growing and bountiful harvests.

Indica vs. Sativa Harvest Trichome Guide

Indica Harvest trichomes guide

If you are growing an Indica strain, it is better to harvest your cannabis plants when the trichomes are completely developed but before they turn amber – unless you want to be couch-locked.

If you extend the flowering period of an Indica cannabis plant, it will dramatically impact its taste and final effect. Fortunately, just extending it by a few days only will not do too much harm.

Sativa Harvest trichomes guide

If you are growing a Sativa strain, make sure that all trichomes are fully developed and 30% of them are amber before chopping your plants.

If you extend the flowering period, you take the risk of decreasing both the taste and the typical Sativa effects. However, there are always exceptions to this general cannabis growing rule of thumb. Certain strains, particularly Haze strains can be extended without sacrificing the typical Sativa effects.