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5 Plant Parts You Need to Know

Leaves, stems, roots, flowers – you know the basic anatomy of plants. But if you’re growing a crop that you want to produce seeds, or to not produce seeds at all, it helps to get familiar with the reproductive parts of plants. That’s right — plants make seeds through a process not entirely unlike how humans reproduce (but without the fun stuff). Some plants have separate male and female flowers. Other plants have all of the vital parts in one flower. Here are the key players and what you need to know about them.


The male parts of a flower consist of an elongated cluster of sacs, called an anther, which emerges atop a thin filament when the flower opens. Inside the sacs are particles of pollen, which sit on the outside of the anther until wind, bees or other pollinators transfer it to the female parts. Together, the anther and filament are known as the stamen (pronounced “stay-men”). If you want your plants to produce seeds or fruit in an indoor garden, you can help by using a small thin paint brush to transfer the pollen grains from the male stamen to the female stigma. If your goal is to get unfertilized flowers with no seeds, you want to snip off the stamen as soon as they appear so none of the pollen is transferred.


On the female side, the pollen needs to land on one of two upright stigmas, one-quarter to one-half inch long, usually pale-colored, that come up from a little green pod called the floral bract. Though it’s only about ⅛ inch across and ¼ inch long, the bract is like the womb: when pollen reaches it through the stigma, a seed develops within each bract and causes it to swell.


The stigma and bract show up first inside a tight cluster of tiny leaf-like sepals. The cluster, called a calyx (say it “kay-licks”), may also contain glands that secrete sticky substances which help pollen grains stick to the stigma.


To further ensure successful pollination, some species produce pistils from the calyx. These thin strands often appear as short, red-orange, “hairs.” The pistils gather pollen from the air and move it down into the plant’s ovary, where it stimulates the production of the seed.


Flower buds typically form on top of a cluster of leaves at the end of a limb, the spots that get the most light. The terminal spots are known as colas (like the soda). Experienced growers use plant-training techniques to increase the number of colas on a plant, which leads to increases in volume and size of the flower buds.

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The Importance of Female Cannabis Plants

In the world of cannabis plants, the females hold almost all the power. Sure, both male and female plants are needed to breed new genetics and create new strains. But female plants are the ones responsible for the sticky and stinky trichome and terpene covered buds we all know and love.

Why Are Female Cannabis Plants So Important?

Anyone who uses cannabis medically or recreationally will know that buds that have seeds are often less potent and considered substandard. On the other hand, buds that are seedless, often coated in sticky resin and even a blanket of white crystals, are highly sought after for their aroma, flavor and most of all, their potent effects. Seedless buds are known as "sensimilla" – female cannabis plants that have been left unfertilized and left to concentrate on producing buds.

Female cannabis plants are the ones responsible for those flavorful, THC and CBD packed buds. On the other hand, it is a male plant that produces seedy buds that are often less potent. While seeds are important to continue growing, in the end more female plants are needed to ensure high yields of quality buds. However, it must be noted that, whilst female cannabis plants are generally more cannabinoid-packed, male cannabis plants can contain unique cannabinoid ratios of their own (particularly CBD), and keeping a lookout for unusually frosty male cannabis plants could make them excellent candidates as fathers for a particularly attractive female!

Female Northern Lights (Afghan) cannabis varietal in flowering. Author: User Dan. Source: Wiki Strains/Wikimedia Commons. CC BY-SA 3.0.

Considering when planted cannabis seeds will come out 50/50 male to female ratio, this means that only half of your crops will yield the types of buds you’re after. There are ways around this that we will look at later, including cloning and feminized seeds, which exist solely to solve the need for an abundance of female plants.

How Can You Tell a Male from a Female Cannabis Plant?

Generally, a cultivator can visually determine the gender of a cannabis plant around 4 to 6 weeks into the growth cycle (though this may differ when growing indoors). At this point the plant is transitioning from its "vegetative" stage to the "flowering" stage when buds are formed.

Cultivators pay careful attention to the space between the nodes of the plant where leaves and branches extend from the stalk. Pre-flowers will begin to form, and the characteristics of those pre-flowers will determine the gender of your plant. In female plants those nodes will show as almost hairlike, while on male plants it will be the shape of a small ball. Male plants also tend to have thicker stalks and grow a bit taller than female cannabis plants.

Male cannabis indica plant. By RR Khalid. From Flickr. CC BY 2.0.

What About Hermaphrodite Cannabis Plants?

Though it’s unusual, just like in humans, there are rare cases where a plant is found to have both male and female pre-flowers. Often, hermaphrodite cannabis plants occur when a plant becomes excessively stressed due to things such as damage to the plant, bad weather, disease, nutrient deficiencies, or of course poor genetics. They can occur in indoor grows as well, when the plant receives excessive light during its dark time.

While a hermaphrodite plant is not ideal, it will still produce pollen, so growers need to be careful to separate these plants along with male plants as soon as they are discovered as they can potentially ruin an entire crop.

Hermaphrodite cannabis plant. From Grow Weed Easy.

Cannabis Clones, Mother Plants, and Feminized Seeds

Earlier we talked about options that allow you to skip the 50/50 gamble and ensure that you are growing all female plants. One option, often used by growers, is to use cannabis clones. A cloned plant is one that is started from an existing plant. The grower simply cuts off a portion of the female cannabis plant and then plants it in a nutrient rich soil that is meant to make the plant take root. Once it does, it can be cared for as any other cannabis plant.

Mother plants are the ones that clones are cut from. Generally, these plants are chosen for their strong genetic background and for exhibiting the qualities being looked for in a particular strain (i.e. a uniue phenotype). For those looking to choose a mother plant, a good rule of thumb is to look at its roots – are they strong, white and numerous? Then you have a good candidate for a mother! A good mother can also be used to make new and interesting cannabis varietals. Some growers, after they’ve found a good mother and have used it for several grows, may fertilize it with a male cannabis plant with similarly good roots and plant structure. This can also increase hybrid vigor, as well as saving unique plant genetics.

Another option, which is often the best choice for those looking to grow at home, is feminized seeds. These seeds are exactly what you would expect, ones that will produce only female plants. This ensures that you skip the 50/50 and get to keep the yields from 100 percent of your crops when it comes time to harvest.

Cannabis clones under light, ready to go straight into 12/12. From Flickr. By Susie Plascencia. CC BY-SA 2.0.

Growing Your Own Cannabis at Home

If you’re considering growing your own cannabis at home, then it is important to know the differences between male and female plants, as well as the importance of keeping female plants. If you are able to purchase clones or feminized seeds from a dispensary this can simplify things for you incredibly, especially if you’re new to the world of growing cannabis.

Not every state allows you to cultivate medical or recreational cannabis, but many do. Leafwell can help you find out more about the home growing laws in your state, as well as connect you to a physician in your state to start the process of getting you qualified for medical marijuana.