What is Cannabis Trichomes

Written by Review Weed Cannabis & Health Enthusiast
Updated: 2023-07-31
An explanation of how cannabis trichomes work

Table of Contents

Trichomes are tiny crystal-like hair structures that give cannabis flowers their frosty appearance. They are the driving force behind marijuana becoming a multi-billion dollar industry in today’s world. As a general rule, the more trichomes the bud has, the stronger the weed. It is also believed that they contribute to a strain’s particular effects – but the know-how of it is something we are yet to fully understand. What we do know about them, however, is mentioned below.

What are weed trichomes?

Trichomes, coming from the Greek word ‘trikhoma,’ which means hair, are the building blocks of cannabis compounds. These are resin glands that cover the surface of the marijuana leaves, branches, and flowers.

A cannabis plant without trichomes is like a car without an engine – it might look nice, but it won’t get you very far. These tiny structures on the plant’s surface are the site of cannabinoid and terpene production. They hold the true essence of marijuana – including scents and flavours. THC, CBD, CBG, myrcene, limonene, pinene – any cannabis-related chemical you have heard of – are all synthesized and held inside terpenes.

With their complex chemistry and biology, trichomes are the source of the plant’s many therapeutic and recreational effects. The earthy scent of Northern Lights, the incredible head rush of Bruce Banner, are all driven by their trichomes.

Function of trichomes

Trichomes can be considered a result of evolution; they are present in all plant species, not just cannabis. Their main function is to ensure healthy growth, survival, and successful reproduction.

  • Their aroma, for instance, can repel animals from eating the plant.
  • The resin secretion can repel or trap insects when they come in contact with the leaves.
  • Similarly, trichomes can protect the plant from harmful UVB radiation and pathogens.
  • They can help absorb moisture and vital minerals from the soil.
  • The waxy covering of trichomes functions like a barrier from extreme heat and sunlight.
  • Trichomes can help expel harmful toxins.

Types of trichomes

There are two types of trichomes seen in nature: glandular and non-glandular.

An image of capitate sessile, bulbous, and capitate-stalked trichomes.
The three main trichomes commonly found in marijuana flowers.

Non-glandular trichomes offer physical protection to the plant from external stressors like humidity, temperature, and radiation.

Glandular trichomes, meanwhile, are where the real action happens. These produce and hold the metabolites the plant needs for survival and, in our case, the reason to consume cannabis.

There are three types of glandular trichomes: bulbous, capitate-sessile, and capitate-stalked.

Bulbous trichomes

These are the smallest and least well-known type of glandular trichomes found on cannabis plants. These are tiny (size ranging from 10-15 microns), spherical structures that are found all over the plant.

Capitate-sessile trichomes

These are slightly bigger than bulbous trichomes and have a very small stalk, with the glandular head almost directly attached to the plant surface. They are found all over the plant, from the stems and leaves to the flowers. Their width is 20-30 microns.

Capitate-stalked trichomes

These are the biggest of the bunch and can be seen by the naked eye. This variant is most commonly seen on the plant; the trichomes on a properly cured cannabis flower fall under the capitate-stalked category. They have a glandular head, which has a ball-like shape, supported on a long stalk. The head has a waxy layer, giving the sticky feeling we know so well. They have a width range of 50-100 microns and can be 200-300 microns tall.

All glandular trichomes produce and store cannabinoids, terpenes, and flavinoids, but it is the capitate-stalked that are responsible for the bulk of the synthesis and storage.

How do trichomes drive the strain’s unique effects?

Here is a quick recap of what we know:

  • Terpenes and cannabinoids work together to produce effects on the endocannabinoid system, often called the entourage effect. For instance, myrcene is a terpene that promotes sedation, while linalool is well-known for its energizing effects. Flowers rich in these terpenes can produce the respective effects of couch-lock and euphoria.
  • These metabolites of cannabis plants are produced and stored inside the trichomes.

So, does it mean that certain types of trichomes – depending on what kind of terpenes and cannabinoids they hold – can produce specific effects? This is a question that scientists are just starting to answer.

One such attempt has been made in a paper published in the Plant Journal. It notes that sessile and stalked trichomes have different terpene profiles, which implies that a flower rich in only sessile trichomes can theoretically produce different effects than those abundant with stalked ones.

Of course, it is not just the trichomes that contribute to the effect – genetics of the plant also plays an important role. However, trichomes are a universe of wonder, and their better understanding can unlock a bigger world of therapeutic applications.

Harvesting marijuana trichomes

Terpenes appear on the cannabis plant during the flowering stage; usually 6-8 weeks after the plant has been vegetatively grown.

An image showing three phases of trichomes growth - crystal clear, milky white, amber/brown.
The three stages of the trichome lifecycle.

The best time to harvest the flower is when the plant’s trichomes are at their peak ripeness. This can be identified by their crystal, milky-white, and amber colouration. The plant is at its peak potency when the trichomes are primarily milky-white. In contrast, amber trichomes indicate that the plant is ageing and the cells inside the trichomes are starting to die.

This lifecycle of trichomes varies across different strains. That’s why keeping a close eye on the flower is essential. When trichomes turn crystal clear to milky white, the plant is reaching maturity – the transition from this milk-white hue to amber marks the start of degradation.

It is believed that crystal-clear trichomes offer an energetic head high, while a mix of amber & milky white offers a well-rounded experience. If the majority of trichomes are amber-coloured, it means you are in store for a heavy body high.

Cannabis flowers must be handled carefully during the harvesting and curing stages as trichomes are fragile and will break easily. Catalysts like heat, oxidation, and time also contribute to the damage. You can also extract these trichomes from the flowers to make extracts like hash oil, wax, and kief – but they require utmost care and special extraction techniques.

Increasing the yield of trichomes

Increasing marijuana‘s THC levels is directly tied to increasing its trichomes quantity. There are several techniques which can make this happen:

  • Play music for your plants: Research has shown that sound vibrations can stimulate growth; a little mellow music may not really hurt the plant.
  • Adjust the lighting schedule: Trichome production can be influenced by light exposure. Try altering the lighting schedule to provide an extra hour of darkness each day during the flowering stage to boost trichome production.
  • Use organic fertilizers: Organic fertilizers can help stimulate trichome production and promote overall plant health. Consider using natural options like compost, worm castings, and bone meal.
  • Experiment with stress-inducing techniques: Some growers believe that exposure to stress, such as by briefly interrupting the light cycle or subjecting them to colder temperatures, can stimulate trichome production as the plant tries to protect itself. However, these techniques should be used with caution, as excessive stress can harm the plant and reduce overall yield.
  • Use UVB lights: The plant naturally produces trichomes to defend against UV radiation. Hence, using UVB lights can trick the plant into producing trichomes.

In addition to these environmental conditions, the genetics of the seeds also play a huge role in the production of trichomes.


Our understanding of trichomes is limited – with research growing gradually. However, knowing that trichomes are where the goodness of cannabis is stored is enough to respect, value, and cultivate it. When buying marijuana flowers, trichomes can be a key indicator of their quality – a crystal-covered bud will provide a good experience, while a flower with no trichomes may give you little to mediocre high.