Cannabis Plant Anatomy: Structure Explained

Cannabis Structure and Plant Parts Explained Clearly

Updated: August 2026 | Anatomy of the cannabis plant: roots, stem, nodes, leaves, flowers, trichomes and other plant parts explained clearly.
Author: Cannapot Grow Team | Reading time: approximately twenty-five minutes

Anatomy of the cannabis plant – structure of roots, stem, leaves and flowers

The Most Important Points at a Glance

✓ Cannabis consists of an underground root system and, above ground, a stem, side shoots, nodes, internodes, leaves and later flowers.

✓ Nodes are the points on the shoot where leaves, side shoots and later flower structures develop. The sections between two nodes are called internodes.

✓ Typical cannabis leaves are palmate and consist of several serrated leaflets. The shape, size and number of leaflets can change during development.

✓ Male and female cannabis flowers differ clearly. Female flowers have ovaries and stigmas, among other structures, while male flowers develop pollen-producing stamens.

✓ The resinous covering of a female flower often referred to as the “calyx” in cannabis terminology is botanically usually a bract. Terms such as calyx, bract, pistil and stigma are therefore often confused.

✓ Glandular trichomes are especially dense on female flowers and the adjacent bracts. Many cannabinoids and terpenes are produced and stored in these specialized structures.

✓ Genetics and environment jointly determine the plant’s appearance. Leaf width, internode spacing, branching and growth form can therefore vary considerably.

How is a cannabis plant structured?

The structure of cannabis can basically be divided into the underground root system and the above-ground part with the stem, side shoots, leaves and later the flowers.

Below ground, the main and lateral roots anchor the plant in the substrate and absorb water and mineral nutrients. Above the substrate, the main stem forms the central shoot axis. Leaves, buds and side shoots, among other structures, develop at its nodes, the junction points of the shoot. The sections between two nodes are called internodes.

As development progresses, the appearance of the plant also changes. After the cotyledons, simple true leaves first develop, followed later by the characteristic palmately compound cannabis leaves. As sexual maturity increases, preflowers may become visible before male or female flowers eventually develop.

Plant part	Where is it located?	Important function
Roots	in the substrate	Anchorage and absorption of water and mineral nutrients
Main stem	central shoot axis	Stability and transport of water, nutrients and assimilates
Nodes	junction points along the shoot	attachment points for leaves, buds, side shoots and later flower structures
Internodes	between two nodes	their length influences the distance between the nodes and therefore the growth form
Leaves	at the nodes	Photosynthesis, gas exchange and transpiration
Flowers	on the reproductive shoot areas	Reproduction and, after successful pollination, formation of seeds
Trichomes	on various plant surfaces, especially densely around female flowers	Protection; glandular trichomes produce and store cannabinoids and terpenes, among other compounds

Not all of these structures develop at the same time. We explain in detail how cannabis develops from germination through the vegetative and flowering stages to maturity in the growth stages of cannabis. In this guide, however, we focus on the anatomical structure and function of the individual plant parts.

How is the root system of cannabis structured?

The root system anchors cannabis in the substrate and develops from an initially dominant primary root with increasingly branched lateral and fine roots.

After germination, the radicle first emerges from the seed. It develops into the primary root axis, from which numerous lateral roots later branch off. This increasing branching enlarges the surface area through which water and dissolved minerals can be absorbed.

Young fine roots and root hairs in particular play an important role in absorption. At the same time, the entire root system provides mechanical anchorage. How deeply and widely the roots spread depends on genetics, soil structure, moisture and available root space, among other factors. Fixed statements about a specific root depth are therefore only of limited applicability.

Good to know: The visible size of a plant does not directly indicate how its roots are distributed. The root system adapts strongly to soil structure, water availability and available space.

What functions do the stem, main shoot and side shoots have?

The main stem forms the central shoot axis and connects the root system with the leaves, side shoots and later the inflorescences.

Vascular tissues run through the inside of the stem and transport water, minerals and organic compounds between the different plant organs. The xylem primarily carries water and dissolved minerals from the root zone to the above-ground parts of the plant. The phloem transports assimilates such as sugars in particular to areas where they are needed or stored.

As the plant ages, the stem becomes stronger and can become more woody. Side shoots develop from axillary buds at the nodes. Together with the main shoot, their number, length and orientation shape much of the plant’s later growth form.

What are nodes in cannabis?

Nodes are the junction points along the shoot where leaves, axillary buds and side shoots, among other structures, attach.

The nodes are important attachment points for further branching of the plant. During vegetative growth, leaf bases and axillary buds are located there, from which new side shoots can emerge. As sexual maturity increases, preflowers or reproductive structures may also become visible in the leaf axils.

In young plants, leaves at early nodes are often arranged in opposite pairs. As development progresses, the leaf arrangement can change and become increasingly alternate. This transition is part of the natural morphological development of cannabis.

What are internodes in cannabis?

An internode is the section of the shoot between two consecutive nodes.

Short internodes cause nodes and side shoots to be closer together, while longer internodes contribute to a more elongated growth form. However, internode spacing is not an unchangeable trait of a genotype. Light, temperature and other environmental conditions also influence how strongly the individual shoot sections elongate.

Node and internode can therefore be distinguished easily: The node is the junction or attachment point, while the internode is the section of shoot between two of these nodes.

Cannabis nodes and internodes on the main stem

What types of leaves does cannabis have?

Cannabis develops different leaf forms over the course of its development – from the first cotyledons to the characteristic fan leaves and the smaller sugar leaves near the flowers.

Botanically, the familiar cannabis leaf does not consist of many individual “leaves”, but of several leaflets that together form a compound leaf. A palmate arrangement is typical, in which the individual leaflets radiate from a common area at the end of the petiole.

The number, length and width of the individual leaflets can change during development and differ between different genetics. Even on the same plant, leaf shape can vary considerably depending on position and developmental stage.

What are cotyledons?

Cotyledons are the first leaf-like organs to become visible above the substrate after germination.

They differ clearly from the typical cannabis leaves that develop later and do not yet have their characteristic serrated, multi-part form. Shortly afterwards, the young shoot produces the first true leaves, whose shape changes progressively during further development.

What are fan leaves in cannabis?

Fan leaves are the large, characteristic foliage leaves and are among the plant’s most important photosynthetically active organs.

They typically consist of several elongated, serrated leaflets. Their large surface area captures light, while stomata enable gas exchange and transpiration. The leaf veins supply the leaf with water and minerals and connect it to the vascular tissue of the shoot, through which assimilates produced during photosynthesis are also transported onward.

What are sugar leaves?

Sugar leaves are smaller leaves around female inflorescences that are often noticeably covered with glandular trichomes.

The name refers to the glittering appearance of the trichomes, which seem to be coated with crystals. Botanically, they are still leaves. They differ from large fan leaves mainly in their position, smaller size and often higher trichome density.

Leaf type	Typical position	Characteristics
Cotyledon	on the young seedling	simple, not yet characteristically serrated and palmate
Fan leaf	on vegetative and reproductive shoots	large, palmately compound, important for photosynthesis
Sugar leaf	around female inflorescences	smaller and often densely covered with glandular trichomes

Cotyledon - fan leaf - sugar leaf: what cannabis leaves look like

Where do preflowers and sex characteristics develop?

The first visible reproductive structures typically develop at the nodes or in the leaf axils, where leaves and side shoots attach to the main or lateral shoot.

In these areas, male or female preflowers can develop as sexual maturity increases. Anatomical differences are already visible at this early stage: female structures develop carpels and stigmas, while male flower primordia form stamens and later pollen-producing anthers.

This article primarily covers the anatomical location and structure of these organs. If you want to determine the sex of a plant based on visible characteristics, you can find the practical distinction in our guide to identifying male and female cannabis plants.

How do male and female cannabis flowers differ?

Male and female cannabis flowers have different reproductive organs: male flowers produce pollen, while female flowers contain the ovules and structures that receive pollen.

Characteristic	Female flower	Male flower
Main function	Reception of pollen and formation of a seed after successful fertilization	Production and release of pollen
Reproductive organs	Ovary with ovule as well as style and stigma structures	Stamens with anthers
Prominent visible structure	two elongated stigma branches protrude from the enclosing bract	hanging or stalked flowers with pollen-producing anthers
Glandular trichomes	especially dense on bracts and leaves close to the flowers	much less pronounced than on female inflorescences

Cannabis is often dioecious, meaning male and female flowers develop on separate plants. However, plants can also occur that develop male and female reproductive structures simultaneously or successively. We discuss the practical classification of such cases separately in the article about the hermaphroditic cannabis plant.

How is a female cannabis flower structured?

An individual female cannabis flower contains an ovary with an ovule and forms two prominent stigma branches. It is enclosed by a resin-rich perigonal bract.

In a mature female inflorescence, many of these individual flowers are packed closely together. This creates the compact appearance commonly referred to as a “bud” or cannabis flower. Botanically, such a bud is therefore not one large individual flower, but a complex inflorescence made up of numerous individual flowers and the surrounding structures.

During flower development, numerous glandular trichomes form especially on the bracts close to the flowers. The two stigma branches protrude from the enclosing bract. Their surface bears fine papillae that play an important role in capturing and binding pollen.

Structure of a female cannabis flower with bracts, stigmas and trichomes

What are bracts and what does calyx mean in cannabis?

The small green structure, often heavily covered with trichomes, that tightly encloses an individual female flower is frequently referred to as the “calyx” in cannabis terminology. Botanically, however, it is usually a perigonal bract.

A bract is a specialized or modified leaf closely associated with a flower. In female cannabis, this flower-adjacent bract almost completely encloses the ovary and is often densely covered with glandular trichomes.

The botanical term Calyx actually refers to the calyx of a flower, meaning the collective sepals. In cannabis, the perianth is highly reduced. The visible resinous covering called the “calyx” in grower terminology therefore does not simply correspond to a classic floral calyx. Since the term is used very frequently in cannabis texts, it is still useful to know both terms.

Botanically more precise: When growers refer to the “calyx” of a female cannabis flower, they often mean the trichome-covered bract that encloses the actual individual flower.

What are the pistil, style and stigmas?

The visible structures of a female cannabis flower often described as “white hairs” are botanically the stigmas – not the entire pistil.

The pistil comprises the female reproductive structures of the flower. These include the ovary, style region and stigma. In cannabis, the two elongated stigma branches are especially visible and initially usually appear whitish to yellowish.

Numerous fine papillae are present on the surface of the stigmas. They increase the surface area and help capture and retain pollen grains. As they age, the stigmas can change color, curl and eventually dry out.

What are trichomes in cannabis?

Trichomes are fine outgrowths of the plant surface. Cannabis has both non-glandular and glandular trichomes.

Glandular trichomes are particularly important for the production of numerous cannabinoids and terpenes. They occur at high density especially on the bracts of female inflorescences. Depending on their structure, stalked capitate, sessile capitate and very small bulbous glandular trichomes are distinguished, among other types.

These glandular trichomes contain specialized secretory cells. Numerous secondary plant compounds are produced and stored in the gland head. The large number of these trichomes also creates the typical resinous and glittering appearance of female cannabis flowers.

How is a male cannabis flower structured?

Male cannabis flowers have stamens with anthers in which pollen grains are produced.

Unlike the usually dense female inflorescences, male inflorescences appear looser and more highly branched. Individual male flowers have five greenish to yellowish perianth segments and five stamens. As they mature, the flowers open and the anthers release their pollen.

If a pollen grain lands on the receptive stigma of a female flower, a pollen tube can grow from it. The male gametes travel through this tube to the ovule. After successful fertilization, a new seed can eventually develop from the ovule.

Male cannabis flower with pollen sacs and anthers

What are pollen sacs in cannabis?

The term “pollen sac” is commonly used in cannabis terminology for the initially rounded male flowers or their pollen-producing structures.

Botanically speaking, pollen is produced in the anthers of the stamens. Before opening, male flowers often look like small closed spheres from the outside. As development progresses, they open so that the individual flower organs and eventually the pollen-releasing anthers become visible.

Where are cannabinoids and terpenes produced?

A large proportion of the cannabinoids and terpenes characteristic of cannabis are produced in specialized glandular trichomes, which occur especially densely on female flowers and the bracts surrounding them.

The gland head contains specialized secretory cells that produce various secondary plant compounds. These substances accumulate beneath the outer cuticle of the trichome. This creates the characteristic spherical head that is clearly visible under high magnification in many mature glandular trichomes.

Cannabinoids and terpenes form an extensive topic of their own, which we cover in more detail in our Cannabis Knowledge section. For the anatomy of the plant, what matters most is where its most important production and storage structures are located: on certain plant surfaces and especially concentrated around female inflorescences.

How does the structure change during development?

The structure of cannabis does not remain the same throughout its life cycle: leaf shape, leaf arrangement, branching and reproductive organs change as development progresses.

After germination, the cotyledons appear first, followed by the first true leaves. At subsequent nodes, larger and more divided leaves as well as new side shoots develop. During the transition from the juvenile to the adult vegetative plant, the leaf arrangement can change, among other things.

As sexual maturity increases, the first preflowers may appear in the leaf axils. Once reproductive development begins, the plant architecture changes further: leaves may become smaller in the upper areas while male or female flowers and increasingly developed inflorescences form.

We cover the complete chronological sequence separately in the cannabis growth cycle. You can also find how female inflorescences in particular develop in our overview of the cannabis flowering stage week by week.

Does genetics influence the structure of cannabis?

Genetic differences influence numerous morphological traits such as plant height, branching, internode spacing, leaf width and flower structure.

However, the visible form is not determined exclusively by genetics. Light, temperature, water and nutrient supply, root space and other environmental conditions also influence the phenotype. Even genetically identical plants can therefore look visibly different under different conditions.

We explain in detail how genotype, phenotype and different generations are related in our guide to Cannabis genetics: F1, F2, BX, S1 and IBL.

Do Indica and Sativa differ in structure?

Cannabis genetics can differ considerably in leaf width, plant height, branching and internode length; however, the simple equation “broad leaf = Indica, narrow leaf = Sativa” is too simplistic for modern genetics.

Historically, certain cannabis groups were described differently based on their origin and morphological characteristics. Many modern strains, however, are complex hybrids. Individual visible traits therefore do not allow reliable determination of their entire genetic ancestry.

Nevertheless, typical morphological tendencies can be observed in different genetic types. The following overview shows some commonly described growth traits and well-known strains as examples. The actual plant form may differ depending on genetics, phenotype and growing conditions.

Genetic type	Typical growth traits	Examples
Indica-dominant	often more compact growth, broader leaflets and comparatively short internodes	Purple Urkle, Granddaddy Purple
Sativa-dominant	often more elongated growth, narrower leaflets and longer internodes	Granny Candy, Princess Haze
Hybrid	combines different traits depending on ancestry; growth form can range from compact to strongly elongated	Toad Venom, Blueberry Pancakes
Autoflowering	same basic anatomical structure; growth form depends on the genetics crossed in, while the main difference lies in the regulation of flowering onset	Gorilla Cookies Auto, Do-Si-Dos-Auto

The examples also show why external appearance alone does not allow reliable classification. Especially in modern hybrids and autoflowering strains, traits from different genetic lines can occur in combination.

We discuss the historical and present-day meaning of these terms in detail in our articles on Indica Cannabis and Sativa Cannabis.

Is an autoflower anatomically different?

Autoflowering cannabis basically has the same important plant organs as photoperiod cannabis: roots, shoot axis, nodes, leaves, and male or female flowers.

The key difference therefore does not lie in a completely different anatomical structure, but mainly in the regulation of development and flowering onset. Autoflowering genetics begin reproductive development more strongly as a function of age and are much less dependent on a shortening of the daily light period for flowering to begin.

We cover the practical characteristics in our dedicated guide to growing autoflowering cannabis.

Anatomy of the Cannabis Plant at a Glance

From the root system to the trichomes, every plant part performs its own function while also being functionally connected to other organs.

Plant part	Position	Function	Special feature
Main and lateral roots	underground	Anchorage and absorption of water and minerals	strong branching increases the absorption surface area
Stem	central shoot axis	Stability and transport of substances	becomes stronger with age and may become partly woody
Node	junction on the shoot	attachment point for leaves, buds and side shoots	important location for preflowers and sex characteristics
Internode	between two nodes	shoot elongation	length is influenced by genetics and environment
Fan leaf	on vegetative and reproductive shoots	Photosynthesis, gas exchange and transpiration	typically palmately compound
Sugar leaf	around female inflorescences	Photosynthesis	often particularly densely covered with glandular trichomes
Perigonal bract	encloses the individual female flower	protection of the flower	often referred to as the “calyx” in cannabis terminology and bears many glandular trichomes
Stigma	protrudes from the female flower	reception and binding of pollen	usually two elongated stigma branches per individual flower
Anther	male flower	Production and release of pollen	part of the stamen
Glandular trichome	on various plant surfaces, especially densely on female flowers	production and storage of secondary plant compounds	different types such as stalked, sessile or bulbous

Frequently Asked Questions About Cannabis Plant Anatomy

What parts does a cannabis plant consist of?

The most important plant parts include roots, the main stem, side shoots, nodes, internodes and leaves, as well as male or female flowers during the reproductive stage. In addition, trichomes are found on various plant surfaces and perform different functions depending on their type.