Weed Buds An Anatomy Lesson

You’ve handled your fair share of cannabis flowers. Whether you’ve watched these tissues form during the flowering stage during a grow, or have only ever handled them before a smoking session, you’ll know a thing or two about them. They smell, they’re sticky, and they have a frosty coating and weird little hairs.

Past these superficial characteristics, cannabis buds are highly complex. They manufacture and store most of the phytochemicals that make cannabis so valuable, including cannabinoids and terpenes. Plus, they feature myriad anatomical components that are difficult to distinguish with the naked eye.

Where Are Bud Sites On Cannabis Plants

If you grow cannabis, you’ll know exactly where bud sites are located on cannabis plants. Colas, otherwise known as terminal buds, form at the end of branches. In untrained and untopped plants, a large central cola forms at the top of the Christmas tree-like structure. This vertical stack of buds can vary greatly in size depending on the genetics of a plant and how it responds to its environment.

Plants also produce many other smaller buds, often called popcorn buds because of their shape. These buds form at the nodes—the point at which petioles (branches) join at the main stem.

The Different Parts of a Cannabis Bud

Cannabis buds are often incorrectly labelled as cannabis flowers. Rather, they are inflorescences—the complete flowering head made up of stems, stalks, bracts, and flowers.

The true flowers of cannabis^[1] are known as pistils. In botany, this term describes the reproductive structures designed to support the pollination process. Cannabis pistillate flowers^[2] are composed of two stigmas, a style, and an ovule protected by trichome-coated bracts. A cluster of pistillate flowers makes up what most growers know as a bud.

Below, we’re going to cover the anatomy of pistillate flowers and buds. We’ll cover all of the important areas, starting from the smallest and working our way up to the largest.

• Calyx

Many cannabis growers often mistake bracts with calyxes. However, cannabis flowers don’t have a distinct calyx. But they do have calyx cells that are found within the perianth, a translucent piece of tissue that partly envelopes the ovule—the site where future seeds develop.

• Trichomes

Trichomes are glands that give cannabis buds their frosty appearance. They don’t look like much to the naked eye. However, up close, these glands take on several different forms. These include:

• Bulbous trichomes: These are small and round

• Capitate-sessile trichomes: These feature a large globular head on a short stalk

• Capitate-stalked trichomes: This type feature a larger head on a longer stalk

Of the three, capitate-stalked trichomes are the main producers of desirable secondary metabolites, such as terpenes and cannabinoids. They produce these compounds in secretory discs and store them in subcuticular cavities. Trichomes produce these compounds for several reasons, including protecting plants from insects and UV rays.

• Stigma

Mainstream cannabis culture has created some confusion when it comes to the stigma of cannabis plants. Each individual pistillate flower produces two stigmas that protrude up and outwards into the open air.

Growers often label these hair-like structures as pistils. Rather, they are components of pistils, but not pistils themselves. Stigmas are covered in tiny hairs known as papillae that help to catch male pollen from the air. When successful, pollen becomes lodged into the side of a female stigma and transfers genetic material that leads to fertilisation. During the flowering stage, stigmas emerge as white and gradually develop an orange/brown colour.

• Bract

Bracts are essentially specialist leaves that are designed to protect the pistil components that they envelop. These fragile structures include the ovule, style, and bottom section of the stigmas. Because bracts protect such precious structures, they are equipped with the highest concentration of trichomes found anywhere on a cannabis bud. Overall, bracts form the main tissue component of manicured nugs.

• Pistils

Unless you have a penchant for botany, you probably assign the label “pistils” to the small hairy protrusions found on cannabis flowers. However, this common misconception confuses stigmas with the entire pistil. Stigmas only make up part of this reproductive structure, alongside the style and the ovule.

• Sugar Leaves

Sugar leaves are small leaves found among cannabis inflorescence. Although much smaller than the larger fan leaves found elsewhere on the plant, they play an important role. As photosynthetic structures, they are able to create vital sugars right where they are needed—close to the buds.

They’re also platforms for trichomes, and therefore offer protection against pests, predators, and abiotic stress. Growers remove sugar leaves after harvesting either before or after drying. Although they lack the dense trichome counts of bracts, many cultivators keep them to make products such as hash.

• Colas

Colas are the buds that form specifically at the end of branches. For this reason, they are also known as terminal buds. Colas are the largest clusters of pistillate flowers anywhere on the plant. When left untrained and untopped, cannabis plants develop large column-like central colas that can weigh impressively heavy.

Females vs Male Cannabis Buds

As a dioecious species, cannabis has distinct male and female plants. Whereas the females develop pistillate flowers that feature two stigmas within a bract, male flowers are made up of the following components:

• Stamen: The pollen-producing part of a flower
• Anthers: The part of the stamen that produces pollen
• Filaments: A structure that supports the anthers
• Sepals: Tissue within which the stamens develops

Early in the flowering stage, male cannabis flowers have a sac-like appearance. Eventually, the sepals open up and the anthers start to release pollen to fertilise female flowers.

Sativa vs Indica Cannabis Buds

Much like with certain aspects of cannabis botany, much confusion revolves around the sativa and indica dichotomy. Over the years, companies have perpetuated the idea that sativa and indica varieties exert specific effects. Because of this, sativa plants are associated with an energising effect and indica with a stoning high.

In reality, things are much more complex than this. Although THC creates the core effects of each cultivar, an array of aromatic terpenes underpin the varying effects. For example, a sativa plant may produce mainly energising terpenes, but it needn’t always be like this.

With that said, indica and sativa subtypes of cannabis do differ in their morphology. Sativa cultivars are taller and have thin leaflets on their fan leaves; indica plants are shorter and display wider leaflets. Adding to these differences, indica subtypes normally produce smaller buds that are more compact, whereas sativa flowers are typically larger and more fluffy.

Dense Buds vs Airy Buds

Several factors determine flower density. As we have just discussed, genetics play a big role. However, bud density can also indicate the quality of cannabis flowers in some circumstances.

Flowers are more likely to develop as dense nuggets loaded with cannabinoids if they are treated to optimal lighting, nutrition, temperature, and humidity. Likewise, a lack of these factors can lead to poor-quality airy flowers with reduced secondary metabolites.

Cannabis Bud Colours: What Do They Mean?

You’ll come across several different colours when looking at cannabis buds. Some of these are genetic, whereas others are environmental. These include:

• Green: Most cannabis buds are green because of their chlorophyll content.
• Purple: Some cannabis buds turn purple because of the presence of anthocyanin, a flavonoid pigment.
• White: Cannabis flowers can sometimes appear white due to young stigmas and high trichome density.
• Orange: As stigmas mature, they start to display striking shades of red and green.

Seeds Forming On Buds

Seeds forming on buds is a sight that most growers try to avoid. Why? Because, unless they’re trying to intentionally breed plants, seeds ruin the quality of cannabis flowers. After fertilisation, the ovule within the bract begins to swell into a seed. This causes plants to divert their resources towards reproduction, and to spend less energy on forming large flowers packed with valuable secondary metabolites.

Weed Buds: A Deeper Look At The Nomenclature

Congratulations. You now have a much better understanding of the anatomy of cannabis buds. No longer will you see a singular object every time you lay eyes on a cola. Instead, you’ll notice individual pistillate flowers, plenty of stigmas, countless trichomes, protective bracts, and energy-producing sugar leaves.