Basic Cannabis Knowledge:


Breeding cannabis is a complicated art that can be performed in plenty of ways. Here, we describe the common terms surrounding various cannabis genetics and how they came to be. We decided to keep it short and concise, as all the scientific minutiae can be very complex.

Landrace varieties originate from regions where cannabis plants have been growing for a very long time in the wild—centuries, or even millennia. This naturally creates stable, robust genetics that produce a homogeneous offspring. This means that the landrace strains from a particular area will develop very similar growth patterns, appearance, and chemical composition. Hindu Kush or China Yunnan are examples of pure landrace strains.

F1 stands for a "first generation hybrid". When two strains with completely different genotypes breed, for example, a Master Kush with Durban Poison, their offspring will be an F1 hybrid. When this hybrid is bred together with another F1 hybrid from the same batch (a sister or a brother), it creates an F2 hybrid. When this process is repeated, it creates an F3, then F4, and so on. After F5, the plants can be considered as IBL.

IBL stands for “inbred line”, meaning that after several generations of hybridising a specific lineage, the strains become almost like a different family of strains. Skunks were hybridized and selected for their very pungent and potent nature, and after many generations, they developed into the Cheese family, which can be called an IBL.

Poly-hybrids derive from mixing completely different hybrids with each other. For example, Master Kush and Durban Poison produce offspring called F1(A); AK-47 and White Widow produce an offspring called F1(B). When F1(A) and F1(B) have a lovechild, it will be coined as a poly-hybrid.

Back-crossing refers to taking a hybrid strain and breeding it back with the original parent. For example, a male Chocolope and a female Jack Herer develop an F1 hybrid. When this F1 hybrid is hybridized with the original female Jack Herer, the resulting strain will be coined as BX1. When this BX1 gets back-crossed again with the original female Jack Herer, it will be coined as BX2, and so on. The genetics of the original female strain can be retained by keeping the plant in the vegetative stage as a mother, keeping the cuttings as clones or using tissue culture propagation.

Selfing is when a mother plant is pollinated by herself. Breeders use special chemicals on female plants to induce stress, which results in the plants producing male flowers, which produce pollen. When this pollen in used on the female flowers of the same plant or a clone from the same mother, the resulting seeds will be “selfed” or coined as S1. When the S1 seeds are back-crossed with the original parent, they’re called S2, S3, and so on. Breeders often do this to preserve the genetics of the strain, and to feminize the seeds.


Genotype and Phenotype:

Many growers tend to misuse the words genotype and phenotype when talking about cannabis. Let’s clear the smoke around this issue and resolve all the unnecessary confusion.


Every living organism is the result of evolution that works by the same basic principle. The genotype or genetic code carries all the genetic information regarding growth, appearance, and all the characteristics we can later observe. It’s crucial to understand that a genotype or genetic code is not something that is set in stone but rather defines a certain range of possibilities. It mainly depends on the environment the organism lives in what specific bits and pieces of the genotype will be activated. The interaction between genotype and environment results in a phenotype, meaning the physical expression of certain genes the environment triggered.

genotype (G) + environment (E) + genotype and environment interactions (GE) = phenotype (P)


Let’s examine a cannabis related example to get a better idea. You purchase seeds from a reputable breeder and intend to grow a purple strain. Instead of growing all plants in your indoor grow tent, you’ll decide on moving half of your plants outdoors. Besides the fact that no plant seems to be identical to one another, you’ll notice that the plants in your outdoor garden are much richer in purple colours compared to the ones in your indoor grow tent. Although the genotype carries the information to produce purple hues, it’s the environment, and in this particular case, the temperatures of the environment, that allow two different physical expressions (phenotypes) from seemingly the same genetic code (genotype).

We got the idea that the environment is the determining factor influencing a genotype to express different phenotypes, but this doesn’t answer the initial question why every cannabis plant grown from seed appears to be slightly different, even when it’s grown in a constant environment of an indoor grow room.

How can a strain express different phenotypes when the environment stays the same?
Well, it’s maybe an inconvenient truth, but every single cannabis seed has its unique genotype. Many growers assume that seeds from the same cannabis strain share an identical genetic code and understandingly expect homogeneous growth. Unfortunately, this is a common misassumption. There are lots of people using the term phenotype to describe the variations of plants they get from the same strain grown from seed. In fact, and what they usually don’t know, they’re talking about different genotypes. It’s not only the environment that determines phenotypic expression, but logically also the genotype itself.

When you purchase seeds of a certain strain, you’ll receive “family members” of this strain that share a large percentage of genetics with thousands of (inbred) siblings, yet they’re not identical twins. The genotype is usually very close to identical, but there are still differences, comparable to fraternal twins if you will. That’s the main reason why every cannabis plant grown from seed expresses slight variations regarding characteristics like plant height, yield, flavour, etc. – the genotype of seeds is usually not identical.



How to Clone Cannabis:
  • Gather your Supplies
    The supplies needed to clone a healthy cannabis plant include a sterile blade, rooting agent, a grow medium (like rockwool), a grow tray with a vented hood, distilled water and a mother plant.
  • Prepare your grow medium
    Rockwool, the most common grow medium has a high pH level and must therefore be treated by first soaking it in a water solution with a pH value of 5.5 (you can adjust this using a digital pH meter and pH adjuster fluid).
After soaking, remove the rock wool and transfer into a mild vegetative nutrient solution with an adjusted pH at around 6.0. When you’re ready to begin the cloning process, transfer the cubes to the grow tray and set aside.

  • Choose your cutting
    Use your sterile blade to cut a 4- to 6-inch branch from the mother plant along the stem at a 45 degree angle then dip the cutting into the rooting hormone. Place the stem of the cutting firmly into the growing medium and repeat (remember to take extra clones some may not survive).
  • Set up your clones
    Clones love moisture, but they need to breathe too. Make sure they’ve got what they need by misting the leaves then securing a dome top in place. Pay close attention to the moisture content (make sure they’re not swimming) and vent when necessary.
Place your clone tray under mild lights (CFLs work great) and watch closely over the next few days. As soon as roots appear, you should transfer the cutting to soil or hydroponic system.

Why do I want to clone cannabis?
There are many reasons to grow Cannabis from clones including a reduced grow time, an indefinite grow cycle and the ability to pre-select female plants. This is especially true for indoor grow rooms that allow for a better controlled environment during all stages of growth.

  • Reduced Grow Time
    A clone should only take a week or two to take root after being removed from the mother. From this point, the clone could continue in the vegetative state until a desired size is reached or be moved directly into its flower phase knocking a few good weeks off of a grow cycle.
  • An Indefinite Supply
    The best buds are seed-free which makes it difficult to keep a constant supply of seeds for the next grow cycle. By taking cuttings off of mother plants, you can keep a constant supply of the same strains that you already know you’ll love.
  • Pre-Selected Female Plants
    A clone is an exact genetic copy of its parent. By taking a clone from a female plant, you’re ensuring that the next generation will be female, too. You can also use cuttings to pre-determine the gender of a plant before introducing the whole thing to a 12/12 light cycle.
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