Cannabis Plant Anatomy: The Parts of the Plant

Published on August 28, 2018 | Last updated August 1, 2024

What does a cannabis plant look like?

There are three major categories of cannabis: indica, sativa and ruderalis. Although other factors, like strain and growth stage, can affect their appearance, there are general characteristics that can help you identify which category a plant belongs to. Here they are:

Indica: Indica cannabis plants are typically shorter and bushier than sativa plants. They usually have broad, dark green leaves and densely packed branches. Indica plants have a shorter flowering time, resulting in compact, dense buds. 

Sativa: Sativa plants are usually tall and slim with narrow, light green leaves and sparse branching. They have a longer flowering period and can produce long, fluffy buds resembling foxtails. Their tall, airy structures and mould-resistant qualities allow them to thrive in humid climates. 

Ruderalis: Ruderalis cannabis plants, frequently found growing in the wild, are small: typically reaching a maximum of two-and-one-half feet tall. They are autoflowering plants, meaning they can transition from vegetative to flowering stages regardless of light conditions, making them ideal for breeding. These plants have broad, jagged leaves and tend to be low in THC content. 

Parts of cannabis plants 

Cannabis plants can be male, female or hermaphrodite. All three produce pre-flowers, or early-stage buds, but only females and hermaphroditic plants fully blossom. 

Flowers: The flowering tips of female plants are the most valued parts of cannabis. They cluster together in what are commonly known as buds. Flower clusters, or buds, contain the plant’s highest concentration of cannabinoids: chemical compounds that contribute to cannabis’s effects. They also contain the plant’s reproductive parts, including bracts, calyxes, pistils and trichomes (more on those below).  

Cola: A cola is a particularly large bud on a female plant. The largest, topmost cola is called the main cola or apical bud and is much-prized by growers and consumers. 

Bracts: These are small, tear-shaped structures that encapsulate the plant’s reproductive elements. Some growers refer to the bracts as “seed pods” since they hold the plant’s ovules, which eventually become seeds.

Calyx: The calyx is the first part of the flower that is formed when a young cannabis plant enters its flowering stage. For female cannabis plants, the calyx is found inside the bract and is responsible for protecting the bud during this critical stage of development. Calyxes are located at the flower’s base and form a translucent covering around the ovule. 

Pistil: The pistil houses a plant’s reproductive system. Pollen is collected through the colourful, hair-like stigmas and is transported to the ovule, where seeds are developed.

Cannabis Seeds: The Cannabis seeds hold the genetic information needed to grow male and female cannabis plants with specific characteristics, including strain, potency and flavour. Cannabis seeds are available in different strains and varieties such as feminized and autoflowering.  

Fan leaves: Fan leaves play a crucial role in photosynthesis. These large, finger-like leaves absorb light and carbon dioxide from the environment to facilitate the production of glucose, which fuels the plant's growth. Even though the fan leaf is an emblem of the cannabis community, it actually contains very little cannabinoid content, though some growers use fan leaves for juicing and tea.

Trichomes:  Trichomes are glands found on the cannabis plant’s leaves, stems and calyxes. Trichomes secrete resin, THC, CBD and terpenes. Under a microscope, they are mushroom-shaped and bulbous. To the naked eye, they give cannabis a sparkly, sugar-coated appearance.  

Stem: The stem of a cannabis plant, like with other plants, is the central support structure that runs from the base of the plant to the top 

Node: The nodes of a cannabis plant are the points on the stem where leaves, branches, or buds grow. Nodes play a crucial role in the plant's plants’ growth and development and can act as a visual indicator of overall health.

How to distinguish male cannabis plants from female cannabis plants 

The sex of a cannabis plant determines its life cycle and its role in breeding new plants and strains. Both male plants and female plants produce pre-flowers, but only female plants produce the highly coveted, cannabinoid-rich buds that growers harvest for consumption. Male plants’ primary role is to pollinate females and facilitate reproduction. 

Male cannabis plants: Male cannabis plants exhibit several distinctive characteristics. They typically appear taller, spindlier and less leafy than female plants. Notably, male cannabis plants do not produce buds; instead, they develop pollen sacs that fertilize female cannabis plants, leading to seed production. Although male cannabis plants aren’t typically consumed as is, they can be processed into concentrates like hash or used in the production of fibres.  

Female cannabis plants: Female cannabis plants are valuable, as they produce the cannabinoid-rich buds prized by consumers. Female cannabis plants have slender stems and are leafier and shorter than male cannabis plants. 

Hermaphrodite cannabis plants: Genetics and environmental factors can sometimes cause a cannabis plant to develop both male and female reproductive organs. These hermaphrodite cannabis plants can self-pollinate, producing seeds without male input. Hermaphrodite plants tend to have lower yields and less potent buds compared to female plants, so growers are careful to monitor conditions to prevent hermaphroditism and preserve the quality and volume of their yield.

The life cycle of cannabis plants

Cannabis plants transition through several growth stages, each with telltale anatomical changes. These stages include germination, vegetation and flowering.  

Germination: A combination of water, warmth and specific light conditions are needed for seed germination. 

From there, a taproot emerges, followed by a stem and the very first leaves called cotyledon. Throughout this week-long stage, the root system develops, as do the plant's first, classic “pot leaf”-shaped leaves.

Vegetation: The vegetative stage is when the plant's stem and root structures grow sturdier to support its growing weight. New nodes, branches and leaves emerge during this stage of rapid growth as the plant begins to form its well-known shape. 

At this point in its life cycle, the cannabis plant has more or less reached its full height, and shifts focus to growing its reproductive structures. Male cannabis plants grow pollen sacs that pollinate female plants, while female cannabis plants produce flowers. By the end of the flowering stage, the female cannabis plant's flowers are large and resinous, and have reached their maximum terpene and cannabinoid potency, meaning they are ready for harvesting. 

Want to learn more about breeding, growing and harvesting cannabis? Learn all about it in our in our Cannabis Basics series.