A cannabis plant is made up of roots, a stem, nodes, branches, leaves and — on female plants — buds formed by calyxes, pistils and trichomes. The leaves change over the plant's life: first come two round cotyledons, then the first serrated leaves, then the large fan leaves with 5 to 9 leaflets and, during flowering, the small resin-coated sugar leaves. Knowing every part helps you understand what is happening to the plant and when it is ready.
If you have ever wondered what a weed plant actually looks like up close, this guide goes through the parts of a cannabis plant from the bottom up: what each one is, what it does and what to look for while growing. We also cover what the weed leaf looks like depending on the genetics, what its colours tell you, how a bud forms and how to tell a male plant from a female.
Parts of a cannabis plant: the overview
This table sums up all the parts of a cannabis plant. We explain each of them in the sections below.
| Part | What it is | What to look for |
|---|---|---|
| Roots | the taproot and the secondary roots in the growing medium | white, firm roots; brown and soft roots point to overwatering |
| Stem | the main axis that holds the plant up and carries water and nutrients | a thick, short stem means good light; a thin, stretched one means too little light |
| Nodes and internodes | the points where leaves and branches grow, and the stretch of stem between them | pre-flowers that reveal the sex appear at the nodes |
| Cotyledons | the first two round leaves that come out of the seed | they yellow and drop after a few weeks — that is normal |
| Fan leaves | the large serrated leaves with several leaflets | their colour and shape reflect the plant's health and genetics |
| Sugar leaves | small leaves growing between the calyxes of the bud | they get coated in trichomes; they are trimmed off after harvest |
| Bud | the flower of the female plant, made up of many calyxes | the main cola is the largest bud, at the top of the stem |
| Pistils | the hairs that grow from the calyxes, white at first, then orange | their colour hints at ripeness, but the trichomes decide |
| Trichomes | tiny resin glands on the buds and sugar leaves | clear, milky or amber: they mark the moment to harvest |
Roots and stem: the base of the plant
The first thing to come out of the seed is the taproot, which grows downwards; many finer secondary roots then branch off it. The roots take up water and nutrients and anchor the plant. They need air as much as water, which is why an airy, well-draining growing medium matters more than watering a lot. Healthy roots are white and firm; if they turn brown, soft and smelly, it is almost always down to overwatering.
The stem is the plant's axis. Water and nutrients travel up it from the roots, and the sugars made by the leaves travel down. A short, sturdy stem shows good light and moving air; a long, thin stem that bends shows the light is too far away or too weak. As the plant ages, the base of the stem becomes woody.
Nodes, internodes and branches
Nodes are the points on the stem where leaves and branches grow. The stretch of stem between two nodes is called an internode. On young plants the leaves grow opposite each other, in pairs; as the plant matures they start to alternate, one on each side — one of the signs that flowering is getting close.
- Short internodes: typical of indica-dominant strains; they give compact plants with tightly stacked buds.
- Long internodes: typical of sativas and of plants grown with too little light; they give taller, more open plants.
- Pre-flowers: a few weeks before flowering, the first tiny flowers appear at the nodes and reveal whether the plant is male or female.
Each node also has a bud in the leaf axil from which a side branch grows. Training techniques such as topping or LST work with these shoots: cutting or bending the tip makes the plant spread its energy over more branches.
The cannabis leaf: four types of weed leaves
The cannabis leaf — the weed, pot or marijuana leaf everyone recognises — is the best-known part of the plant, but it is not just one thing: over the cycle, four types of leaves appear, each with a different job.
Cotyledons: the first leaves
The cotyledons are the two round, smooth leaves that come out of the seed when it germinates. They are already formed inside the seed and feed the seedling for its first days, until the true leaves take over. After a few weeks they yellow and drop off: that is completely normal. If they turn yellow in the first few days, though, it is usually a sign of too much water or feed. How to germinate seeds step by step is explained in how to germinate cannabis seeds, and what the plant looks like week by week afterwards in cannabis seedling stage week by week.
True leaves and fan leaves
After the cotyledons come the true leaves, with the typical serrated edge. The first have a single leaflet (each of the "fingers" of the leaf); the next pairs have three, then five, and so on up to the large fan leaves of the mature plant, which usually have 5 to 9 leaflets and sometimes 11 or more. The number of leaflets is almost always odd.
Fan leaves are the plant's solar panels: they capture light, produce the sugars the plant grows on and store reserves. So don't strip too many of them; only remove the ones shading buds or the ones that have already dried. At the end of flowering they yellow naturally, as the plant draws on its reserves.
Sugar leaves
Sugar leaves are small leaves that grow between the calyxes of the bud. They get their name because they become coated in trichomes and, from a distance, look dusted with sugar. They are trimmed off after harvest; because they carry resin, many growers keep them for extractions.
Indica leaf vs sativa leaf
The shape of the leaf gives clues about the genetics. Indica-dominant strains have broad leaves with short, dark green leaflets; sativa-dominant strains have thin, long leaves in a lighter green. Most modern strains are hybrids, with leaves somewhere in between. All the differences between the two types are covered in indica vs sativa.
What leaf colours tell you
A healthy cannabis leaf is an even green. Colour changes are how the plant warns you of a problem:
- Yellow lower leaves: usually a nitrogen shortage — or simply the end of flowering.
- Yellow between the veins: a magnesium shortage or the wrong pH.
- Burnt tips and very dark leaves: too much feed.
- Purple tones: in many strains they are genetic or appear with cool nights at the end of flowering; they don't always mean a problem.
How to recognise and correct each deficiency is explained, with a table, in our cannabis feeding schedule. And if you are interested in purple plants, you will find all the strains in purple cannabis strains.
The cannabis bud: what it is and how it forms
The bud is the flower of the female plant. It is not a single flower but a cluster of many small flowers packed around the stem or a branch. The biggest bud, at the top of the main stem, is called the main cola; the buds on the side branches are the secondary buds.
Calyxes and pistils
Each flower in the bud is made up of a calyx, a small teardrop-shaped casing (botanically, a bract), from which two pistils emerge: the hairs you can see on the bud with the naked eye. Their job is to catch pollen; if there are no male plants nearby, the flower is not pollinated, does not form a seed and keeps producing resin.
Pistils are white at the start of flowering and, as the plant ripens, turn orange, reddish or brown and curl in. That colour change hints at ripeness, but the exact moment to harvest is set by the trichomes.
Trichomes: where the resin is
Trichomes are tiny glands covering the buds and sugar leaves, and to a lesser extent the large leaves and the stem. They produce the resin containing cannabinoids such as THC, and the terpenes behind the aroma. There are three types:
- Bulbous: the smallest, barely visible even with a loupe.
- Capitate-sessile: with a round head sitting almost flat on the surface.
- Capitate-stalked: the largest and most common on the buds, with a stalk and a round head; they give the plant its shine.
With a 30–60x loupe you can watch them change: first clear, then milky and finally amber. How to use them to decide when to harvest is explained in when to harvest cannabis; what terpenes add to the aroma, in cannabis terpenes.
Male, female and hermaphrodite plants
Cannabis is dioecious: there are male plants and female plants. Only females form resinous buds; males produce pollen and, if they pollinate the females, the females fill their buds with seeds.
- Female: calyxes with two white pistils appear at the nodes.
- Male: small hairless balls appear at the nodes, which open like tiny hanging flowers and release pollen.
- Hermaphrodite: a female plant that, through stress or genetics, also forms male flowers or small "bananas" (anthers) between the buds.
With feminized seeds practically all plants come out female, so there is no need to sort them. How to tell a male plant from a female reliably, with photos, is explained in male vs female cannabis plants.
How the plant changes over the grow
Not every part is there from the start. This table shows what develops at each stage:
| Stage | Parts that develop | Approximate duration |
|---|---|---|
| Germination | taproot and cotyledons | 1–5 days |
| Seedling | first true leaves with 1, 3 and 5 leaflets | 1–2 weeks |
| Vegetative | stem, branches, nodes and fan leaves; pre-flowers at the end | 3–6 weeks (autoflowers: 2–3) |
| Flowering | calyxes, pistils, sugar leaves, trichomes: the buds | 7–10 weeks |
| Ripening | orange pistils, milky to amber trichomes, large leaves yellowing | the last 1–2 weeks |
The whole process, from seed to harvest, is explained in how to grow cannabis, and what happens in each week of flowering in cannabis flowering stage week by week.
Important: Pyramid Seeds sells cannabis seeds as collectible items, and the growing information on our site is for educational purposes only. Whether you may germinate seeds and grow plants depends on the law in your country, and the rules differ widely — please check the regulations that apply where you live before growing.
FAQ: The cannabis plant
What are the parts of a cannabis plant?
Roots, stem, nodes and internodes, branches, leaves (cotyledons, fan leaves and sugar leaves) and, on female plants, the buds, made up of calyxes, pistils and trichomes. Male plants form pollen sacs instead of buds.
What is a weed leaf called?
The large leaves are called fan leaves; each of their "fingers" is a leaflet. The first two round leaves of a seedling are the cotyledons, and the small resin-coated leaves growing between the buds are sugar leaves.
How many points does a weed leaf have?
The fan leaves of a mature plant usually have 5 to 9 leaflets, sometimes 11 or more; the number is almost always odd. A seedling's first true leaves have 1 leaflet, then 3, then 5.
What are cotyledons?
They are the first two round, smooth leaves that come out of the seed when it germinates. They feed the seedling for its first days and, after a few weeks, yellow and drop off naturally.
What is a cannabis bud?
It is the flower of the female plant: a cluster of many small flowers, each made up of a calyx with two pistils and covered in resin-producing trichomes. The biggest bud, at the top of the main stem, is called the main cola.
What are pistils on weed?
They are the hairs growing out of the calyxes on the bud. They catch pollen; they are white at the start of flowering and turn orange or brown as the plant ripens.
What are trichomes?
They are tiny glands covering the buds and sugar leaves that produce the resin with the cannabinoids and terpenes. With a loupe you can see them change from clear to milky and amber, which marks the moment to harvest.
What are sugar leaves?
They are the small leaves growing between the calyxes of the bud. They get coated in trichomes, which is why they look dusted with sugar. They are trimmed off after harvest.
How do you tell a male from a female cannabis plant?
By the pre-flowers at the nodes, a few weeks before flowering: a female forms calyxes with two white pistils, a male forms small hairless balls that later release pollen. With feminized seeds practically all plants are female.
Seeds to see all these parts on your own plant
With feminized seeds, all your plants will be female and will form buds. Pyramid Seeds has bred its own genetics in Barcelona since 2002, with a germination guarantee, free seeds and discreet shipping.
Practically 99% female plants: indicas, sativas and hybrids from our own breeding.
Robust, forgiving strains for your first grow.
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