Anatomy of a hemp flower: calyxes, pistils, bracts, and sugar leaves
|
|
Playback time 5 min
CONTENTS
A hemp flower is made up of several structures, each with its own function. These include calyxes, bracts, pistils, sugar leaves, and trichomes. Let’s take a closer look at a CBD flower so you can finally put the right names to what you see.
Things to remember
- A hemp flower is an inflorescence composed of several distinct plant structures.
- The calyxes, bracts, and pistils have different functions.
- Sugar leaves are rich in trichomes.
The hemp flower is an inflorescence
What does the term “flower” actually mean?
When you buy CBD flowers, you receive what is commonly called a “bud.” However, this term doesn’t really refer to a simple botanical structure. It actually refers to an inflorescence—that is, a cluster of many small female flowers.
Take a close look at a bud, and you'll see that its surface isn't uniform. You can make out small structures packed closely together, protruding filaments, small leaves, and a multitude of tiny resin glands. All these parts make up the structure of the inflorescence.
In hemp grown for its flowers, the female inflorescences are particularly sought after because they contain high concentrations of cannabinoids and terpenes in their glandular trichomes.
Why are female flowers rich in resin?
Cannabis is a plant that produces male and female flowers on separate plants in many varieties, although some plants may have both types of flowers.
Female flowers develop reproductive structures surrounded by bracts and calyxes and bear numerous glandular trichomes.
Calyxes and bracts: the structures at the heart of the flower
The calyx is a small protective structure
When it comes to cannabis flowers, the term “calyx” is a bit unusual. The small structures often referred to as “calyxes” in cannabis-growing terminology largely correspond to the highly developed floral bracts that surround the reproductive organs (don’t worry, I’ll explain all of this below!).
They are small, tightly packed, and usually covered with numerous trichomes, and they make up a significant portion of a flower’s visible volume.
The bract, not to be confused with a typical leaf
A bract is a modified leaf associated with a plant's reproductive structure. In hemp, the bracts surrounding the female flowers are particularly well-developed.
That’s exactly where the terminology can be misleading! In the cannabis world, people very often use the term “calyxes” to refer to these structures, even though the botanical distinction between bracts and true sepals is worth preserving.
For you, the most important thing is to remember where they are located. These bracts surround and protect the flower's reproductive structures and are covered with a high density of trichomes.
Why are these structures covered with trichomes?
Bracts and floral structures are among the areas richest in glandular trichomes. These small glands produce cannabinoids such as CBD, as well as numerous terpenes. This explains the shiny, crystalline, or “frosty” appearance that a flower can take on when it is heavily covered with trichomes.
The resin visible on the surface of a bud comes mainly from these microscopic structures.
Pistils are those filaments you see on flowers
Pistils or stigmas—which is the correct term?
You've probably noticed the little white, yellow, orange, or brown filaments sticking out of a hemp flower. They're often called “pistils.”
In botany, the pistil refers to the entire female reproductive organ. More specifically, the visible filaments are the stigmas, which are located at the tips of the styles.
Their role in reproduction
The stigmas serve a reproductive function. They receive pollen from a male flower.
When a female flower is not pollinated, it continues to develop its floral tissues and trichomes.
Does their color indicate the quality of the flower?
No, not really. The stigmas can change color during development and after harvest. They generally change from light shades to darker ones.
But be careful not to jump to conclusions! Their color does not allow you to accurately determine the CBD concentration, terpene content, or quality of a flower.
Sugar leaves are the small leaves around the bud
Sugar leaves and fan leaves: two different structures
Fan leaves are the plant's large, distinctive leaves. They are primarily used for photosynthesis and are found on the stems and branches.
Sugar leaves, on the other hand, are small leaves that grow directly from the flower clusters. They are generally shorter, narrower, and heavily covered with trichomes . It is this shiny, resinous appearance that gave them their English name: “sugar leaves.”
Why are they rich in trichomes?
Sugar leaves are located in the center of the plant and can bear a significant number of glandular trichomes. They therefore play a role in the production and storage of cannabinoids and terpenes. However, their trichome concentration can vary depending on their location, stage of development, and the plant’s genetics.
Their Role in Trimming
After harvest, growers can remove some of the sugar leaves during trimming to achieve a cleaner flower by eliminating the leaf tissue that extends beyond the inflorescence. The extent of trimming varies depending on production methods.
It is therefore largely within these tiny structures that the resin of interest to producers of CBD flowers and extracts is found.
Article written by Benjamin Poirel-Nadal
Passionate about natural well-being and plants with multiple virtues, I've been exploring the benefits of CBD and its various forms for several years.
My aim? To share with you clear information, honest opinions and practical advice to help you integrate CBD into your daily life with confidence and serenity.
