There is something truly magical about growing from seed – From opening the endless void of genetic possibilities when germinating new seeds to the unique whirl of flavors and aromas that each plant will produce. Whether you are germinating 3 seeds or 3,000 seeds, there are always new discoveries to be found.
Growing Cannabis from seed will ultimately result in more hardy plants for your specific grow environment. This is because seeds always introduce more genetic variability than cloning, you may find that some of your plants may perform really well in your environment, where others might not. Propagating plants asexually through cloning does not give you this same flexibility. If you were to grow from only clones, and those plants don’t perform well in your environment – they will suffer because they are all, in essence, the same plant. Clones can also bring in foreign pests and diseases into your garden which your current soil biology and environment may not be ready to handle. The sharing of cuts among friends and family can be extremely rewarding, however proper sanitation of the clones before being moved into their new grow environment is a necessity, especially if the root zone is shared.
Below we have listed out the common questions clients should ask their seed vendors before purchasing cannabis seeds.

Autoflower or Photodependent?
Growers will have to make the decision whether they want to grow what is called a photodependent plant, which is dependent on changes in light cycles to trigger flowering, or an “autoflower” variety, which grows in a predictable time period independently of exposure to light. Autoflower plants often go from start to harvest within 3 to 5 months depending on the variety, and are typically much smaller than the average photodependent Cannabis plant. Different Cannabis varieties will take more or less time to reach full maturity for harvest. If you are cultivating outside, you will want to consider your local weather patterns and identify plants that can be harvested before the threat of rain, snow or heavy wind that could damage the crop or lead to contamination. If you are concerned about having proper lighting or are growing in a small confined space, autoflower varieties may be the best way to start your growing journey.
How Were The Seeds Produced?
The next thing you will want to find out is how the seeds were produced. When plants are bred, they are bred into “filial generations” which are labeled F1, F2, F3, F4, and so on. F1 is the youngest filial generation and F4 is the oldest filial generation by this example. Through selective parental and offspring breeding over numerous generations Cannabis breeders are able to stabilize dominate traits. When two different varieties of plants are crossed, an F1 generation is produced, which generally expresses mostly similar traits and many of the plants exhibit similar phenotypes (the phenotype is the way the plant looks, smells, etc). F2 generation plants will exhibit a ton of variation due to the expression of homozygous recessive genes. As breeders continue to select for favorable traits, they keep pressing down the filial generations until they reach a stabilized inbred line, or IBL. Inbred lines are achieved when favorable traits are being consistently expressed throughout a generation. The majority of Cannabis seeds for sale on the market are polyhybrids because of the constant crossing of an F1 generation to another F1 generation instead of using two IBL’s. A polyhybrid population will show drastic differences in phenotypic expressions. True F1s are produced when two separate inbred lines are crossed.
So what filial generation should I be purchasing? F1 and IBL seeds will be the most expensive seeds that you can purchase and will be the most rare. Why? because these seeds have taken the most time to produce. For novice growers we recommended purchasing F2 and F3 seeds then working your way up to F1 and IBL seeds. Hopefully by this time you have established a healthy garden area and grow routine to make sure your are giving the genetics their best conditions to shine. If you are looking for predictability such as a medical patient or hobbyist breeder, you will want purchase F1s or IBLs. Keep in mind that true F1s are produce from inbred lines and breeding with IBLs should provide reliable F1 phenotypes.

What is the Germination Rate?
So you understand what filial generations are – what’s next? Next we want to understand the germination rate for a seed. The germination rate is a description of how many seeds out of one hundred seeds you should expect to germinate successfully. Germination is the process by which the seeds take on water and start the process of vegetative growth. This is also called “popping” or “cracking” seeds.
Generally you never want a germination rate that is not less than 50%, and ideally closer to 80% or better when possible. This way you know that you will at least get plants from at least half of the seeds you buy. Given the cost of Cannabis seeds (which is expected to drop as legalization continues across the United States), you definitely want to ensure you are getting your money’s worth.
When you are asking about germination rates, be sure to ask the seed vendor how the germination rates were measured. Did they actually try to germinate 100 seeds at once? Or even better, 1000 seeds at once? Or did they only do their test with 10 seeds? Statistically, the more seeds that are included in the germination study, the more reliable the result will be.
What is the Feminization Rate?
The next thing you will want to find out is how likely each seed is going to produce a female cannabis plant. This is because it is female cannabis plants that produce the cannabinoid and terpenoid rich resin that people use to make medicines, edibles, cosmetics, etc.
Feminization rate is reported as a percentage (%) similar to germination rate. And just like with the germination rate, you will want to find out how the producer calculated their feminization rate. Generally you never want a feminization rate that is not less than 50%, and ideally closer to 70% or better when possible. This way you know that you will at least get female plants from at least half of the seeds you buy. Most cannabis seeds for purchase are regular seeds which produce both biological male and female plants. However, you can purchase feminized seeds which should produce only female cannabis plants.
When asking a seed vendor about feminization rates, it’s also good to ask them about their experience with hermaphroditism in the plants. Hermaphroditism is when a plant exhibits both male (staminate) and female (pilstillate) flowers on one plant which can pollinate each other so that the plant can produce seeds. If possible, you are going to want to find out whether the plants that start off as females actually stay females through the entire grow cycle, or whether some of them “flip” and become hermaphrodites. A high feminization rate that results in plants that are very sensitive to stress and hermaphroditism is not helpful.
Common Phenotypic Expression?
After finding out all of this preliminary information, you are ready for the fun part – understanding the differences in how different Cannabis varieties grow and express themselves.
Phenotypic Expressions to Consider
- What do they smell like when flowering?
- Are they tall and narrow or short and wide spacing?
- Are they prone to pest and diseases?
- How well did they withstand drought and temperature change?
- What color flowers and stigma are produced?
- What is the typical time from seed to harvest?

Other Considerations
My seed purveyor showed me a certificate of analysis that says these plants will test at 30% THC
Certificates of Analysis for crops grown from seeds mean very little for future crops of plants that will be grown by a different person in a different environment. Just because someone was able to grow a plant from a set of seeds and were able to harvest and get a test result at some high percentage means absolutely nothing to the client purchasing the same seeds. Potency is affected by many variables including sunlight exposure, nutrient availability in the growth medium, and environmental stressors to name a few.
Finally, a plant’s chemistry is influenced by its environment. This is especially true when we talk about Cannabis since its desired compounds are grown on the outside of the plant! Terpenes – the bulk fraction of a plant’s essential oils are commonly used by companies as a marketing point to sell seeds. While the ratios of cannabinoids generally remain predictable when cultivating a Cannabis plant from a stable line of seeds, the terpene profile can still vary substantially.
The bottom line: when it comes to seeds, take certificates of analysis with a grain of salt.
What about strain names?
Strain names are brand names and should be thought of as such. For the most part, strain names are not strongly correlated with either genetic lineage or the chemical profile of the plant. This could only be consider to be reliable if the IBL seeds or clones of a specific strain are purchased from the same farm or breeder consistently.
The Takeaway
The main things to remember when purchasing Cannabis seeds are the following:
- Are the the seeds I am purchasing regular or feminized?
- Am I purchasing a photodependent cultivar or an autoflower?
- What filial generation are the seeds I am purchasing?
- And finally what are the germination and feminization rates of the seeds?
The goal is to look for anything close to or above 70%.