How to tell if cannabis seeds are good or bad?

Cannabis seed breeders work hard to deliver the best genetics they can. The best, most established seed suppliers have extensive original seed archives and access to the best modern cuttings. The most stable varieties are the result of ruthless selection from dozens of seed-grown plants. But how can you use visual clues to know if your seeds are good are bad?

What do good cannabis seeds look like?

The cannabis community is full of views, opinions and hearsay about the key attributes of good, viable cannabis seeds. Some growers even claim to be able to distinguish between feminised seeds and autoflower seeds based solely on visual clues. Not all of these beliefs are correct - and Dutch Passion have made some revealing time-lapse cannabis seed germination videos to dispel some of the myths.

Healthy brown colour

Many traditionalists look for cannabis seeds that show a healthy, wood-like, brown lustrous exterior sheen. Some even steer their strain choices to strains/suppliers known to deliver large seeds with a healthy brown colour.

But after many years of experience with different strains, Dutch Passion know that different strains produce seeds with different colours. Some strains typically produce shiny brown seeds with a tiger-stripe exterior. But other strains never show these colours, instead producing seeds with lighter creamy of even a near-white appearance.

Such colours, contrary to popular opinion do not indicate that your cannabis seeds are necessarily bad or will fail to germinate. However, cannabis seeds that are prematurely harvested (different strains have different seed-ripening rates) may show a green, immature appearance with reduced germination rates. But experienced breeders should know precise details about their strains which allow them to tailor each seed batch to perfection.

Check out the Dutch Passion germination video test, below, made with 18 Auto Think Different seeds. The autoflower seeds were produced from the same batch of seeds. The 9 darkest seeds were taken and so were the 9 lightest.

White vs Dark Cannabis Seed germination test from Dutch Passion on Vimeo.

The side-by-side germination test showed the same 100% germination rates from both the light seeds as well as the dark seeds. The only difference was that the lighter coloured seeds were slightly faster at germinating. One theory behind this is that the lighter coloured seeds have a slightly less-hardened shell and therefore germinate a little faster.

Optimal size and shape

Many old-school growers prefer large seeds, feeling that smaller seeds are the result of premature harvesting or bad genetics. Some are quite certain that small cannabis seeds are bad. Yet some strains never produce large cannabis seeds.

Small cannabis seeds are quite normal for some strains. Many strains routinely produce large and small seeds from the same batch. The key is to remember that the final plant genetics are determined by the contents of the seed embryo. The exterior size, or appearance, can vary.

Small vs Big cannabis seed germination from Dutch Passion on Vimeo.

To demonstrate this, Dutch Passion took 9 large cannabis seeds (5-6mm in size) and made a side-by-side germination test with 9 small (2-3mm) seeds. The results showed all the seeds germinated, with the smaller cannabis seeds germinating slightly faster can the big ones.

A theory behind this is that larger seeds may simply take longer to open and be discarded by the seedling. It’s also worth noting that some of Dutch Passion’s largest outdoor strains (capable of reaching 3-4m (10-13ft) tall such as Purple #1 and Passion #1 come in small cannabis seeds ..despite growing to such huge final proportions.

No signs of cracks / damage

If your cannabis seeds are cracked or have significant exterior damage then they may not be viable, i.e. capable of being germinated. Most serious cannabis seed suppliers take great care to check their seeds prior to commercial sales and ship them in crush-proof, humidity-proof packaging. For the best companies this means germination tests on each seed batch. Speak to your seed supplier if ever you receive damaged cannabis seeds or poor germination rates.

Autoflower seeds vs feminised seed differences
Despite many theories to the contrary, there is no visual way to identify feminised seeds from autoflower seeds. The genetic code that determines the type of cannabis plant is held in the seed embryo. Likewise, visual examination can’t tell the differences between feminised seeds or regular cannabis seeds.

How to determine if your cannabis seeds are viable

When looking at their cannabis seed collection the inevitable thought often occurs to the nostalgic collector; “will they actually germinate?”  Here are some key dos and don’ts.

The ultimate test: germinate your cannabis seeds

Even very old seeds (fridge-stored for several years) can be germinated. But the chances of germination decrease as the seeds age. Try germinating your seeds if in doubt - there is nothing to lose, and you may find a keeper or two. The most recommended and reliable ways to germinate your cannabis seeds is to germinate them in your grow medium or between damp cotton pads.

Cannabis Seed Germination: The Cotton Pad Method from Dutch Passion on Vimeo.

Beware of the cannabis seeds float/sink test

One common myth claims that cannabis seeds that sink straight away in water are good, and the seeds that float on top of the water are doomed to a germination fail. The theory behind this is that the seed embryo has started decomposing, releasing small quantities of gas into the seed shell and increasing buoyancy in water. However, some viable seeds may also float, meaning that the float test can’t be relied on and is not recommended by Dutch Passion.

Avoid squeezing or cracking your cannabis seeds

Some specialist ‘seed cracking’ tools are available that squeeze the cannabis seed until the nutshell just cracks. Seeds are then germinated in the usual way. The theory is that by cracking the thick woody shell open it makes for an easier germination.

These tools have been used by seed companies but only for germinating ancient seeds that have known low germination rates. Seed cracking tools are definitely not recommended for home growers since the risk of seed damage is greater than the benefits offered when dealing with fresh weed seeds.

Where do you buy weed seeds from?

Buy fresh cannabis seeds from an established supplier and you should get professionally bred, and stabilised seeds with germination rates of 95% or more. The older, more well-established seedbanks tend to offer the best quality/consistency/support but some of the better smaller suppliers also deliver solid genetics & service and are worthy of consideration.

A few cannabis cup wins (Dutch Passion have around 100 after 35+ years of breeding) is a sure sign that your seedbank takes their craft seriously and are sufficiently confident to be benchmarked against the best of the competition.

Dutch Passion offer a full range of autoflower seeds, feminised seeds and regular seeds with literally thousands of repeat growers. They are also one of the few cannabis seed suppliers to offer independent lab-analysis for both terpenes and cannabinoid content on most of their strains as well as an archive of customer grow reviews and cannabis grow guides written by experts. If you’re on a budget check out the Dutch Passion cannabis seed sale, where you can find many best sellers at half-price or below.

If you’re baffled by the wide-range of seeds you may wish to check out the Dutch Passion seed finder that asks you a few questions about your grow requirements, space availability & time before recommending the most suitable strains - it’s easy and takes just a few seconds to make the best selection. Enjoy your next grow!