Phenotypic selection, or pheno-hunting or phenotyping, is the process of selecting an individual based on the set of observable characteristics resulting from the interaction of its genotype with the environment.
When we apply this to the selection of a cannabis plant, these observable characteristics are the colours, tastes, smells, bud structure, trichome production, cannabinoid potency, and terpene profile.
Choosing genetics can be extremely subjective and is based on the goals of the grower.
Different Stokes for Different Folks
A Commercial Grower prefers to choose genetics like dense bud structure, heavy trichome coverage, and higher levels of cannabinoids and terpenes. They are looking for the best overall product. While some phenotypes may have higher potency or better bud structure, commercial growers want a happy medium between high potency and produce.
More medicinal or craft growers may want to isolate the highest potency possible despite other characteristics.
These growers may want extreme therapeutic or psychoactive properties. Those not found in some other phenotypes with better bud structure or colour expressions. They may find that producing high potency medicine is the top priority over yield. Some growers seek to isolate the best colours or aesthetic qualities for artful purposes. These growers love the look of the cannabis plant and grow them for the aesthetic value they possess. Cannabis can fade into beautiful colours, and the stems can be interwoven to produce living art. When grown around rocks and other bases, cannabis plants can be trained and pruned into any shape.
The Story of my Pheno Hunting
As you can see in my example, I am currently hunting just two seeds of a cultivar named Black Nitro.
Even though the choice is only limited to two phenotypes, my goal is to find the best overall product based on my set of priorities. I will choose the one I stick with after the grow is harvested and cured. If neither one meets my criteria for adoption to my stable of mother plants, then I won’t keep it. My reason for the pheno-hunt is to find mothers that I want to keep and reproduce with many times.
Only genetics that absolutely pass all my criteria will be kept. Further production will be through clone only.
Black Nitro #2 (left) has larger colas and is inches shorter than Black Nitro #5. They both have similar trichome coverage and scent profiles.
The largest difference between the two phenotypes is in the colour and bud density. Black Nitro #2 has purple in the flowers, whereas Black Nitro #5 is green at this point. #2 also has a better bud structure which would lead to a higher yield. As long as everything progresses like it is, #2 would be my pick as the better phenotype.
Black Nitro #2 on left, Black Nitro #5 on right. Notice the purple on the left, whereas there is none on the right. Also, the left side is denser looking.
As with the pictures above, the left specimen in the below pictures exhibits a much denser bud structure, while the sample on the right has a more open structure. Again, it is my opinion that the specimen on the left has better qualities.
Each Day Brings new Pheno Hunting Gains
Both plants are on day thirty-one of flower in the pictures below.
Even though I have a clear favourite, thirty-one days only represents half of the flowering period. So much more is to be learned from the growth of these two phenotypes. Flower maturity and bulking will take place in the last stages, and the terpene profile will mature. Given a proper cure, the potency of the plants will have the final say in whether one gets added to my stable of favourite genetics.
If my favourite so far # 2 comes out to be less potent than #5, and # 5 picks up the budding, then I will have a decision to make. #2 may not develop the prominent levels of cannabinoids and terpenes desired and be eliminated. I may not pick either. Some growers would go a step further and breed the two together to try to hunt the density of the #2 pheno with the potency of the #5 pheno.
As the end of the cycle approaches, these phenotypes are putting on a show. Day 49 pictures show much more dense and mature buds.
Black Nitro #2 lived up to the hype, producing rock hard buds with great colour and trichome coverage. Black Nitro #5 bulked up as well, just not as consistently as #2. The terpene profiles just based on scent alone are wildly different. Black Nitro #2 has more of a heavy sweet smell (limonene and caryophyllene) and #5 has a sweet skunky smell (myrcene).
Pheno-hunting comes down to picking a set of characteristics in an individual that are desired and then growing seeds until that individual is found. It’s not rocket science!
Most people have a set profile they look for when choosing cannabis. I also have my favourite terpenes and flower profiles. The hunt for desired characteristics is exciting and mysterious because every seed holds the chance for a completely unique experience.
It’s exciting to see something you love take shape in a way that is different from the others while being in the exact same environment. In going through the process, you will find out what you like and do not like in the realm of cannabis.
I am continually surprised by new experiences and finding new elements that impress me about the wonderful world of cannabis cultivation. It truly is whatever you make it. Let us make it amazing, my friends.