The cannabis plant has several structures, many of which we can find on any ordinary flowering plant species. Cannabis grows on long skinny stems with its large, iconic fan leaves extending out from areas called nodes.
Cannabis really stands out in its flowers—or buds—where unique and intricate formations occur: fiery orange hairs, sugary crystals, and chunky buds enveloped by tiny leaves.
Parts of the cannabis plant
Seeds are produced in female cannabis plants and carry the genetics of a male and female. Seeds need to germinate to sprout and will grow a taproot, which will become the main root that anchors the plant.
These are the first leaves to grow from the seed after germination. They usually come in pairs, and seeing them is a sign of successful germination and that your plant is on its way to growing healthy and strong.
The roots grow down from the main stalk of the plant into the soil. When growing from a seed, the main root is called the “taproot.” Roots are the lifelines of a cannabis plant, pulling water and oxygen into the plant so it can grow healthy and strong.
Mycorrhizae, a beneficial fungus, can be added to soil to improve root systems.
The main stem, or stalk, of a cannabis plant grows straight up from the root system and supports all lateral branches. The stem gives a plant structure and stability.
Often, growers will top, or cut off, the stem after about five nodes, which forces the plant to grow out laterally more, creating more bud sites.
Branches grow out of the main stem and support fan leaves and buds. Growers often train a cannabis plant by topping branches to create more bud sites.
A node is a point at which a branch grows off of the main stem, or one branch from another branch. Fan leaves and buds can grow on some nodes, but not necessarily all.
When determining the sex of a cannabis plant, pre-flowers, or the beginnings of male and female sex organs, will appear at the nodes.
The space between nodes is called “internodal spacing” and will give you a sense of whether a plant will grow tall or short.
Fan leaves are the large, iconic leaves of the cannabis plant. They capture light for the plant and typically have little-to-no resin and are usually discarded when trimming.
Sugar leaves are the small, resin-coated leaves that buds form around. Sugar leaves are usually saved as “trim” during harvest and can be used for pre-rolls, extracts, and other cannabis products.
Also known as “buds,” the flowers of a cannabis plant are the fruits of your labor. They contain the cannabinoids and terpenes that get you high or offer health benefits. Flowers only grow on female cannabis plants and must be dried before consumption.
A cola, also called a “bud site,” refers to a cluster of buds that grow tightly together. While smaller colas occur along the budding sites of lower branches, the main cola—sometimes called the apical bud—forms at the top of the plant.
Bract and calyx
A bract is what encapsulates the female’s reproductive parts. They appear as green tear-shaped “leaves,” and are heavily covered in resin glands which produce the highest concentration of cannabinoids of all plant parts.
Enclosed by these bracts and imperceptible to the naked eye, the calyx refers to a translucent layer over the ovule at a flower’s base.
Stigma and pistil
The pistil contains the reproductive parts of a flower, and the vibrant, hair-like strands of the pistil are called stigmas. Stigmas serve to collect pollen from males.
The stigmas of the pistil begin with a white coloration and progressively darken to yellow, orange, red, or brown over the course of the plant’s maturation. They play an important role in reproduction, but stigmas bring very little to the flower’s potency and taste.
Despite their minute size, it’s hard to miss the blanket of crystal resin on a cannabis bud. This resin is secreted through translucent, mushroom-shaped glands on the leaves, stems, and calyxes.
Plants originally developed trichomes to protect against predators and the elements. These clear bulbous globes ooze aromatic oils called terpenes as well as therapeutic cannabinoids like THC and CBD. The basis of hash production depends on these trichomes and their potent sugar-like resin.
Why Sex Cannabis Plants? The Role of Male and Female Plants
For the most part, the average home grower wants female cannabis plants. The ladies are the ones that produce the fattest, most resinous and most potent flowers – aka buds. Male cannabis plants are only desirable if someone wants to breed cannabis and save seeds (which is a whole other topic for another day). Even then, the grower will want to spot the difference between the male and female plants and separate them early on, unless they want free cross-breeding and pollination between many types of stains.
Not only are the males less desirable, but male cannabis plants interfere with the quality and production of your female plant. Males grow pollen sacks, and produce pollen. When a female cannabis plant becomes pollinated by a nearby male, her energy shifts into producing seeds.
Like most things in nature, female cannabis plants have a biological drive to reproduce. After the deed has been done, she will sit back and relax. While a pollinated female cannabis plant WILL still develop decent size buds, they are usually lower quality and contain less THC and other desirable cannabinoids. Not to mention, they’ll be full of seeds. When left un-pollinated, a female cannabis plant’s flowers (buds) will continue to swell, develop more trichomes and become increasingly resinous. She is trying to get as sticky and large as possible to catch pollen in the wind. That sweet sinsemilla – aka unfertilized, seed-free cannabis.
When to Sex Cannabis Plants
Our goal here today is to learn how to tell the difference between male and female cannabis plants early on, so you can get the males away from the females as soon as possible! It will help protect your lady plants – but also spare you the wasted time, resources, and energy of tending to male plants that you don’t intend to keep.
Keeping in mind that every strain and grow set-up (e.g. indoors, outdoors, daylight hours) creates varying circumstances, most cannabis plants begin to pre-flower as early as 4 weeks after germination. By week 6, the pre-flowers begin to reveal their gender and you should be able to identify the sex using the tips to follow. Once the plants go into full flower (8 to 10 weeks on average, for a natural outdoor grow) the differences between male and female plants will be glaringly obvious. We’ll talk more about exactly what each sex looks like in a moment.
Until we can tell the sex for sure, we continue to treat the plants equally. We start our seeds in small 4-inch nursery pots. About two weeks after germination, we pot the seedlings up into an approximately two-gallon (trade size) “sexing pot” like these BPA-free nursery pots. This enables everyone to continue to grow in a happy and healthy manner for several more weeks*. Then, once we can surely tell the difference between the male and female cannabis plants, only the ladies move into their forever home – 15 to 25 gallon grow bags full of recycled organic living soil.