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!
For most of us, our introduction to cultivation comes when we buy or are gifted some cannabis seeds for the first time, so let’s set out on our examination of cannabis anatomy starting with the seed.
A healthy, mature cannabis seed will be well-rounded in shape with one pointed end and one flat end. They have a tough outer casing that is rigid to the touch, preventing the seed from being easily crushed. A seam separates the two halves of the shell (also known as the hull or pericarp) and is where the seed opens during germination.
Depending on their genetics, seeds can vary greatly in size, from really tiny (800 seeds per gram) to absolutely massive (15 seeds per gram). In mature seeds the outer shell should be covered with attractive dark markings known as “tiger stripes” which, like snowflakes, are unique to each seed and are in reality a thin layer of cells coating the seed and can be rubbed off easily, revealing the true tan/beige colour of the seed beneath.
When we germinate a cannabis seed, the first thing that emerges from the opened seed will be the tap root which will begin to grow downwards, seeking out moisture and nutrition and colonising the substrate. The root system has three main purposes, not only does it anchor the plant in the substrate, it provides it with water and the nutrients, and it also acts as storage for sugars and starches produced by photosynthesis. It’s hard to overstate the importance of the roots in cannabis cultivation, they really are the foundation upon which everything else is built, without healthy roots we won’t harvest beautiful flowers!
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
The stem, which can sometimes be hollow, is divided by nodes where the lateral branches begin, with the space between them being known as the internode. Seedlings will begin by growing opposite pairs of nodes and leaves but as time passes the nodes will start to grow alternately, sign the plant is mature and ready to flower.
Taller, stretchier Sativa plants will have a larger internode spacing than squat, compact Indica varieties, although environmental factors can also influence internode space. The nodes are where the first flowers appear (pre-flowers), so it’s the first place growers look when trying to determine the sex of plants grown from regular seeds. The small, narrow spear-like leaf growing at each node is called the stipule, and shouldn’t be confused with pre-flowers.
Nodes are one of the parts of the cannabis plant where most growth happens and most hormones are produced, for this reason we always cut clones with at least one node to be planted below ground in the substrate, so it can produce auxins (rooting hormones) to begin root development in the undifferentiated meristem cells of the node.
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.
growing the parts of the cannabis and understanding their roles can help you pick out the highest quality strains. In this post, we will covering the anatomy of the female cannabis plant, because the males do not produce cannabis flower we all know and love.
Just like most plants, cannabis begins with roots that transition into a stam. The cannabis stem is long and thin. The intersections between new stem offshoots and older stems is called the Node. The nodes are used to tell the sex of the plant, as indicators to when the plant is ready to be pruned, at the plant’s temperature needs. Then there are the iconic marijuana fan leaves, and at the very top is the cola, which is where the flower blooms from. There are numerous colas amongst the budding sites below the main cola at the top.
The flower itself originates from a small nodule called the calyx. These small nodules are shaped like a water drop are what form the flower itself. Nodes normally have a large collection of trichomes on them.
Trichomes are the glands that secrete cannabinoids. When you look at a flower, the shining crystals on the tiny leaves, called sugar leaves, the crystallized secretions of Terpenes, THC, CBD, and other cannabinoids. An flower with a lot of these crystallizations will have higher cannabinoid counts, and typically be higher quality bud.
Finally, come the pistils. The pistils are the small, orangish brown, hairs that sprout from the flower. Although the pistils and a certain amount of aesthetic pleasure, they barely effect the potentency or flavor of the bud.