Quality cannabis seeds start with good genetics, but how those seeds are tested, handled and stored matters too. At MSNL, we carry out our own in-house germination testing on seed batches, use independent laboratory germination and purity testing, and grow genetics at our test facility in the Netherlands to check characteristics that can't be assessed from the seed alone.
Stage 01 · Viability
In-House Germination Testing
One of the most straightforward ways to assess a batch of cannabis seeds is to actually germinate them.
We run our own germination tests on every batch of seeds. This allows us to see how seeds from a particular batch are performing and check that they're germinating to the level we expect. For practical growing instructions, read our guide to germinating cannabis seeds.
How we carry out in-house germination tests
For each batch test, we want to see a taproot break through the shell and reach around 1-2 cm in length within 2-4 days. This gives us the confidence that seeds from that batch are germinating as expected before they're sent to our customers.
Running these tests ourselves is also one of the reasons we're able to offer a germination guarantee. We're checking the performance of every batch rather than simply assuming the seeds will germinate.
Stage 02 · External verification
Independent Germination & Purity Testing
Alongside our in-house testing, we also submit selected seed samples from each of the breeders we work with to independent laboratories, including NIAB, for germination and purity testing. Because independent laboratory testing is carried out on representative samples rather than every individual strain or batch, it provides an additional external check alongside the in-house germination testing we carry out on every batch.
What the tests assess
Germination testing measures the proportion of seeds in the submitted sample that successfully germinate under the laboratory's testing procedure, while purity testing assesses the physical purity of the submitted seed sample.
Stage 03 · Sex expression
How We Test Feminized Cannabis Seeds
Germination testing can tell us whether seeds are viable, but it can't tell us everything about the plants those seeds will eventually produce.
With feminized genetics, we also need to check that the seeds produce female plants at the 99% or higher rate we expect. This is important because, unlike regular seeds which can produce both male and female plants, feminized seeds allow you to focus on growing flower-producing female plants without having to identify and remove males.
The only way to properly test this is to grow the genetics until they begin flowering.
We grow plants at our facility in the Netherlands and, as they reach the flowering stage, monitor their development and check for female sex expression as pre-flowers and flowers begin to form. This allows us to verify something that simply can't be determined by inspecting or germinating the seed alone.
Stage 04 · Genetic expression
Test Growing Our Cannabis Genetics
Some characteristics only become apparent once you grow the plant from seed to maturity.
That's why cultivation forms another part of how we evaluate cannabis genetics. At our breeding and phenotype testing facility in the Netherlands, genetics can be grown and observed beyond the germination stage.
A test grow allows us to look at characteristics that a germination test simply can't show, including how plants develop, their structure, flowering behavior and the characteristics expressed by different plants within a genetic line.
It's an important distinction. A seed germinating successfully tells us it's viable. It doesn't tell us what kind of cannabis plant it will become.
Our test grows allow us to learn more about the genetics we're working with and provide practical information that can feed back into how strains are selected, evaluated and described. Growers interested in breeding can also explore our regular cannabis seeds.
Stage 05 · Viability protection
How We Store Our Cannabis Seeds
Testing a good batch doesn't mean much if the seeds aren't looked after properly afterwards.
Cannabis seeds are living biological material, and their environment during storage can affect how well they retain their viability over time. Heat, moisture, light and fluctuating storage conditions are all things we want to minimize.
That's why our seeds are kept refrigerated at approximately 4-6°C while in storage.
Seeds are protected inside vials and branded Mylar packaging before being kept under refrigerated conditions. This helps protect them from light, moisture and unnecessary environmental fluctuations while they're waiting to be sent to customers. For practical home-storage advice, read our guide to storing cannabis seeds.
The unglamorous details matter.
One little detail that customers rarely get to see is that a lot of seed quality control isn't particularly glamorous. Sometimes it's Petri dishes on a table. Sometimes it's checking plants. Sometimes it's simply making sure seeds are packaged correctly and the storage temperature is where it should be.
But these small things matter when you're dealing with seeds that may remain in storage for extended periods.
Why several checks matter
Our Approach to Quality Control
We've been selling cannabis seeds since 1999, and one thing we've learned is that you can't judge seed quality from appearance alone.
A healthy-looking seed still needs to germinate. A seed that germinates still needs to develop into the type of plant its genetics are supposed to produce. And even a good-quality batch needs to be stored correctly if you want to maintain that quality.
That's why we approach testing at several different stages rather than relying on a single check.
The photographs and laboratory reports on this page aren't intended to suggest that every individual seed will behave identically. Cannabis seeds are biological products and natural variation exists. They're here to show you something we think is more useful: what we do behind the scenes to test, evaluate and look after the seeds we sell.
Experience behind the process
Contributed and reviewed by experienced cannabis specialists.
Cultivation contributor
Stoney Tark
MSNL lead cannabis cultivation writer
Stoney contributes more than a decade of hands-on experience as a cannabis grower, breeder and author, with particular expertise in breeding and cultivation practice.
Editorial reviewer
Jack Cooper
Cannabis writer, editor and Head of SEO
Jack provides research-driven editorial oversight for MSNL content covering cannabis cultivation, seed genetics and industry data, with a focus on accuracy and responsible information sharing.
Good to know
Cannabis seed quality-control FAQs
Clear answers about what our testing shows, what it cannot show and how seeds are protected before dispatch.
Does MSNL germination-test every cannabis seed batch?
Yes. We carry out an in-house germination test on every seed batch so we can check batch-level performance before seeds are sent to customers.
What does a successful in-house germination test look like?
For each batch test, we want to see the taproot break through the shell and reach approximately 1-2 cm within 2-4 days under our test conditions.
Why use independent laboratory testing as well?
Independent testing gives us an external, documented assessment of a submitted sample. It complements our first-hand batch checks rather than replacing them.
How can feminized cannabis seeds be tested?
Sex expression cannot be assessed from the seed or a germination test. The genetics must be grown until flowering, when pre-flowers and flowers can be monitored for female expression.
At what temperature does MSNL store cannabis seeds?
Seeds are stored under refrigerated conditions at approximately 4-6°C. They are protected inside vials and branded Mylar packaging to reduce exposure to light, moisture and unnecessary environmental changes.
Do the tests guarantee that every individual seed or plant will behave identically?
No. Cannabis seeds are biological products and natural variation exists. Our tests provide evidence about batch performance and genetic behavior under the relevant test conditions; they do not mean every individual seed or plant will be identical.
Quality from batch to dispatch
Choose genetics backed by a process you can see.
Explore MSNL cannabis seeds or read the germination guarantee before choosing your next grow.
