Marijuana News in Canada

Cannabis Breeding: How are New Strains Created?

cannabis breeding

When you see our list of strains on HighClub or visit the Leafly Strain Database, you’ll quickly realize that there’s a treasure trove of strains available out there.

But what goes into strains, hybrids, crosses or backcrosses? All these are part of plant breeding, which basically involves the breeding of a male and female plant to bolster their genetics.

When we breed two strains, we get hybrid strains.

When cannabis breeders embark on combining strains, their main mission is to strengthen or purify strains or to combine the traits of strains.

They also do this to enhance aroma potency, or to increase yields among many other reasons.

Before growing and breeding cannabis, you first need to know the origin of your seeds and what they were crossed with. If seed sellers can’t give you with the genetic information of the seeds you’re buying, there’s really no way of knowing what you’re working with.

Like with most other plants, breeding is a fundamental aspect of growing cannabis. Given its technical nature, usually done at a commercial scale. With Canada and many states legalizing weed, cannabis breeding becomes popular. The good news is that you can do it at home in your small cannabis garden.

The Basics of Breeding

Like with any other plant, cannabis plants are either male or female. However, most people only care for the female plant as it produces sticky buds that are well-loved by consumers.

They forget that the male plant is equally important — especially when it comes to breeding — as they are a necessity in the pollination of the female plants. A good example of this is the Super Lemon Haze strain. This is a cross between the Lemon Skunk and Super Silver Haze parent strains. The breeders saw some good traits in both strains and chose to join them together. In order to breed cannabis, you need a male and a female of the two strains you’re combining.

First, you use the pollen of the male plant to pollinate the female one. Once this is done, the female plant will produce seeds with the characteristics of both strains. All you need to do is to harvest the seeds and grow them to get a hybrid strain.

So how do you go about selecting the male or female of the strains you want to breed?

Nat Penington, founder/CEO of the Humboldt Seed Company, said that the female traits seem to manifest themselves more in the seeds than those of the male plant. He added that the grower won’t have problems noticing the male plant because it’s technically different from the flower.

How to Breed Cannabis Plants

Once you’ve selected the two parent plants and set them aside for breeding, you’ll first need to introduce them to a breeding chamber. For small-scale breeders, a breeding chamber can be an enclosure created by plastic sheets on all sides. For large-scale breeding, a sterile environment is preferred.

As a practice, place one male plant alongside a number of female plants. The male plant will produce pollen that pollinates the female ones. According to experts, a single male pollinates tens of females, so its a good thing to make sure you have only one male at a time in the breeding chamber. Penington said that a single male can cover tens of females with seeds.

He calls this ‘intentional breeding’.

Once in the chamber, it’s recommended that you let the plants grow vegetatively for a few weeks in order to get bigger. However, this is not a necessity. All you need to do is to subject your plants to 12 hours of light and 12 hours of darkness.

Basically, the male plant produces pollen sacs within weeks as it reaches its flowering phase. Once this is done, pollen is released from the sacs. It moves through the air and lands on the female plants that are then pollinated. And this is essentially why the chamber comes in handy.

It prevents pollen from leaving the enclosure while simultaneously blocking female plants from getting pollinated from the outside. You can help by physically taking pollen from the male plant and applying it to the female plant. Once pollinated, the female plant will continue to grow.

It gets covered with seeds and a bud: the two features that make it different from a male plant. Mature seeds are then collected and dried.

Pennington says the plant has to die for the secondary phase of pollination to take place. He adds that the seeds will need to be dried first before they can be replanted.

So do you harvest the flower and the seeds at the same time? According to Pennington, you need to harvest flowers three to four weeks before the seeds. Once the new hybrid seeds have been dried, they can be planted in an open environment away from the breeding chamber.


It’s important to note that the process doesn’t end there. If you buy your seeds from a shop, chances are the breeders have done several breeding cycles to strengthen or purify the strains. They do this to achieve consistency.

Every seed is different and carries different traits. Some carry traits of the male plant, while others take after the female plants. All these seeds with different variations are called phenotypes. Heterozygous seeds produce phenotypes with a variety of traits while homozygous ones have phenotypes of similar genes.

With cannabis, it’s best to have homozygosity to make sure we have seeds with a similar genetic makeup for consistency. Buyers will want to buy seeds with the same genes over and over again. This is also the reason why large-scale breeders select phenotypes with the best traits for mass production.

Let’s go back to our earlier example of Super Lemon Haze.

This strain takes the bud, trichome structure and resin production traits from the Super Silver Haze strain, but keeps the aroma of the Lemon Skunk. Lemon Skunk has loose buds and can grow to become extremely tall in comparison to Super Silver Haze, which instead has dense buds and grows shorter. Breeders select the phenotypes with the traits they like. In this case, they select the ones with the structure of the Super Silver Have and the aroma of the Lemon Skunk. But this doesn’t mean there weren’t phenotypes with different traits from the ones above. They were there but were deliberately discarded.

Essentially, breeders refine the traits of their selected phenotypes by repeating the breeding cycle over and over again. In the case of the Super Lemon Haze, they kept on growing the phenotypes with the traits that we all know today as Super Lemon Haze.


Breeding is comprehensive — and it doesn’t end here.

Once the breeder has narrowed down on the one phenotype, he backcrosses it to make its genetics more robust. It’s similar to inbreeding. All a breeder does is to cross-pollinate the phenotype with a similar one or a parent. The background makes the phenotype more homozygous, making sure that the desired qualities will continue flowing from one generation to another.

The seeds that you buy from a shop could have gone through various processes of breeding. From the breeding chamber to the selection of the desired phenotypes to crossbreeding, the breeding process needs lots of time and patience.

Pennington says that to be a breeder, you need to accept that you will not always get uniform offspring as this will need a lot of time and patience. You also need to accept that you will have to do lots of backcrossing in order to get a strong strain that you want.

Check Out Our Current Hybrid Strains



The mostly sativa Nuken is a Canadian strain bred by combining genetics from Kish (a cross of two Shishkaberry parents) and God Bud. Her even-keeled effects are delivered alongside a sweet, earthy aroma of fresh herbs and grass.

Nuken typically leaves you functional enough to still enjoy hobbies and the company of friends. Nuken blooms with rounded, dense buds covered in a blanket of crystal resin veiling its sage hues

Blue Rhino


Blue Rhino is a potent cross of Blueberry and White Rhino that has a unique fruity aroma mixed with some skunky harshness. This plant may be of special interest to growers for its large flowers, which will get to their most impressive size when grown outdoors.

Patients like this strain for its balanced mix of head and body effects, making it an option for staying focused or wanting to relax, depending on your needs

Girl Scout Cookies


GSC, formerly known as Girl Scout Cookies, is an OG Kush and Durban Poisonhybrid cross whose reputation grew too large to stay within the borders of its California homeland. With a sweet and earthy aroma, GSC launches you to euphoria’s top floor where full-body relaxation meets a time-bending cerebral space. A little goes a long way with this hybrid, whose THC heights have won GSC numerous Cannabis Cup awards. Patients needing a strong dose of relief, however, may look to GSC for severe pain, nausea, and appetite loss.

There are several different phenotypes of the GSC strain including Thin Mint and Platinum Cookies, which exhibit some variation in appearance and effect. Typically, however, GSC expresses its beauty in twisting green calyxes wrapped in purple leaves and fiery orange hairs.

Sour Diesel


Sour Diesel, sometimes called Sour D, is an invigorating sativa-dominant strain named after its pungent, diesel-like aroma. This fast-acting strain delivers energizing, dreamy cerebral effects that have pushed Sour Diesel to its legendary status.

Stress, pain, and depression fade away in long-lasting relief that makes Sour Diesel a top choice among medical patients. This strain took root in the early 90’s, and it is believed to have descended from Chemdawg 91 and Super Skunk.

One thought on “Cannabis Breeding: How are New Strains Created?

  1. flamand4201 says:

    Love reading these…so helpful…especially how to make my own seeds at home..
    Will definitely try..

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