In order to take best care of your cannabis plants, it is necessary to have a basic understanding of cannabis plant anatomy.
Anatomy is the area of biology which describes and identifies the internal and external components and structures of all living things. Anatomy covers three main areas: animals (zootomy), humans (human anatomy) and plants (phytotomy). Anatomy is further sub-divided into macroscopic and microscopic anatomy. Macroscopic Anatomy relates to parts which can be seen with the naked eye, for example: the branches and leaves of the cannabis plant. Microscopic Anatomy relates to parts of the cannabis plant which can only be seen under a microscope, such as cells.
The word “Cannabis” is from the ancient language of the Romans, Latin, and before that “Kannabis” from Greek. Cannabis plants are dioecious, from the Greek word meaning “two households”, and have distinct male and female forms. Cannabis plants sometimes become hermaphrodite and both male and female characteristics will show on the same plant. This usually happens because the cannabis plant has been stressed in some way.
Having distinct sexual characteristics means it is possible for growers to sex their cannabis plants. We will describe the most important structures of the cannabis plant and their function, as we consider this to be essential information for growers to give the best care to, and obtain the most from their favourite plant!
Most people will have seen a plant at some point, and will know about the basic external structures, such as stem, leaves and roots. It is important for growers of cannabis plants to pay attention to these, as they are helpful in identifying problems with disease or nutrient deficiencies.
The roots of the cannabis plant are fibrous, and made up of many long, slender parts. The basic structure consists of the primary or ‘tap’ root, plus secondary roots and finer roots – all covered in tiny hairs. Roots allow the cannabis plant to receive water and nutrients. They also anchor it in the soil or other grow medium. The goal of the grower is to keep the root system as strong and healthy as possible in order to obtain maximum yields. A healthy root system will be white and well-developed, growing throughout all of the available medium in the pot. The size of the pot used will affect the overall efficiency of the cannabis plant root system. It is difficult to get big yields from cannabis plants that have a small root system.
The main stem grows from the primary root. It is one of the most important parts of the cannabis plant, because it holds the entire aerial structure of the plant. Secondary stems grow from the main stem. Stems are a kind of skeleton for plants, supporting the stalks and leaves. They consist mainly of calcium and plant cellulose. Besides holding the aerial parts of the cannabis plant, stems also contain vascular vessels where the sap is transported up and down inside the plant. The sap to a cannabis plant is like our blood:- a transportation solution of water and nutrients.
Nodes are the points along the stem where the stalks of leaves and lateral branches grow. Leaves usually grow in opposing pairs, with growth nodes appearing just between the leaf base and stem or branch where it is growing.
Inter-node is the space between each pair of nodes.
Stipules are formed each side of a leaf at the base in some cannabis plants. They look like a tiny lance or dagger, located at the nodes of the cannabis plants. The function of stipules is not known, but they may be there to protect new leaf shoots. In other plants, stipules become thorns.
Attached to the stem and branches are small stalks called petioles, which terminate in the leaves of the cannabis plant. In nature, leaves come in many different shapes and sizes. Cannabis plant leaves are palmate or digitate, meaning they are divided into finger-like lobes which emanate from the base of the leaf. The edges are usually serrated with leaves normally growing in alternating opposing pairs.
Leaves are like a cannabis plant’s solar panels, the energy industry centres of photosynthesis. As you may recall, photosynthesis is basically a chemical process in which light, energy, water and nutrients are used to produce sugar and other organic compounds. During photosynthesis the plant absorbs carbon dioxide (CO2) and releases oxygen (O2). During hours of darkness, photosynthesis stops and cannabis leaves give out carbon dioxide (CO2). Without plants, life on our planet would be impossible. This is why it is so important to take care of every single plant or tree. Cannabis plants mature very quickly, and can produce large amounts of oxygen. If you take care of your plants, they will take care of you and the world we live in.
Pay special attention to your cannabis plant’s leaves. Being one of the visible parts of the plant, they are like an open book speaking to us about plant health and development. Healthy leaves are indicative of a healthy plant.
"Stomata" means "mouth" in the Greek language. Stomata is a microscopic structure located on both upper and lower surfaces of the leaf, but mainly the lower surface. Stomata are like adjustable valves and can open or close, according to weather conditions and needs of the plant. Their main function, opening and closing, is to allow the exchange of oxygen, carbon dioxide, and water vapor between the inside of the plant and the external environment.
Cannabis plants show their sexual traits when they reach the stage of flowering, first ones appears behind stipules. The uncommon feature that distinguishes the male cannabis plant, is the sexual organ called the stamen. The stamen is composed of the anther (pollen sacs, like a small ball or an egg, approximately 5 millimetres) and the filament (holds the anther to the plant). When mature, the sac opens and the pollen grains fly in the air, hopefully to reach the pistil of a waiting female plant. Its main function is reproduction.
Females have different features which are possible to recognise. They too, appear at the beginning of the flowering stage, first ones also behind stipules. -The female sexual organ consists of the calyx holding the pistil inside. The calyx measures 2 to 6 millimetres in length. Calyx for different cannabis plant strains may vary in size, shape or colour: from soft green to deep purple. This is the part of the cannabis plant which is covered with lots of trichomes.
The pistil is like a tiny hair protruding from the calyx. Its purpose is to catch pollen and fertilise the plant. Deep inside the calyx is the ovary where the seed will develop after the plant is fertilised. Among cannabis growers, ‘pistil’ usually refers to both the upper and lower parts. There also exists the stile, a part connecting the ovary and stigma. The stigmas may vary a little, and in some strains appear in red or white in colour.
In her effort to attract pollen, the female cannabis plant develops lots of calyxes and pistils which grow into clumps or clusters. Bud can have different sizes, types, colours, etc,. depending on the strain and genetics.
The Cola appears in the upper parts of the branches. It’s the big bulky looking structure on the main stem. Several bud formations on female cannabis plant tops clump together to form what the cannabis world calls a "cola". Its main purpose is to catch airborne pollen and produce lots of seeds.
One of the most important parts of cannabis plant anatomy is the trichome. There are various types of trichome in the cannabis plant. Glandular trichomes are the ones most sought by growers because they contain the most cannabinoids and terpenoids, or as High Times said “the good stuff”. Glandular trichomes appear on the surface of pistils, but also on the smaller leaves close to the buds. These smaller leaves can have many, many trichomes and often look as though covered in frost. They are sometimes called ‘sugar leaves’. The basic function of trichomes is keep the seed safe and protect it.
Small hairy trichomes and encrusted trichomes exist on all cannabis plants. Whilst male cannabis plants do not produce glandular trichomes, they do have these small hairy trichomes on their leaves and stems, as well as encrusted trichomes.
Trichomes exist in nature in many different types, shapes, and sizes. Several other species of plant have trichomes on their surface too, such as tomato, tobacco and nettle.
We hope you enjoyed this article and obtained some basic and important info about the anatomy of the cannabis plant.