How to Spot Bad Cannabis Seeds [Comprehensive Guide]
You may not realize it, but the quality of your cannabis crop is, in part, determined before you have even begun. Seed quality is an enormous part of growing, so it’s vital to source marijuana seeds from a reputable company.
Sometimes, you can end up with ‘bad’ cannabis seeds that will cause problems later down the line. In some cases, these seeds just won’t germinate. Although this won’t ruin your entire crop, it is a waste of time and money, which can be frustrating.
Today, we will help you work out whether your cannabis seeds are good or bad. Hopefully, this guide will help you to determine which seeds are worthy of your time and which ones are duds.
What Makes a Cannabis Seed ‘Bad’?
A ‘bad seed’ is any cannabis seed that will cause problems. In some instances, this means a dud seed that never sprouts, wasting your valuable time and a few resources. While dud seeds aren’t damaging, they are irritating.
Another type of bad seeds is male cannabis plants. There’s a 50/50 chance with regular seeds as to whether any given seed is male or female. The problem is that male plants will pollinate the females once they reach maturity, destroying the valuable THC content of female plants.
Having male cannabis plants in your garden is basically a recipe for disaster, so you want to avoid it at all costs. By the way, here’s how to figure out if your plants are male or female.
One way around this is to purchase feminized marijuana seeds. In theory, all seeds in a feminized bunch will be female – unless you buy from a disreputable grower. Unfortunately, there’s no way to tell whether a plant is male or female simply based on the seeds.
This guide will only cover how to tell the difference between a potent seed and a dud seed.
The complete guide…
How to Test Cannabis Seeds
There are several easy methods for testing cannabis seeds. Most of them can be performed before germination, saving you some time and resources. Let’s find out how to check your seeds.
Method #1: The Sight Test
Cannabis seeds are surprisingly beautiful. They have a mottled brown appearance with patches of light and dark, and sometimes gorgeous tiger stripes. The seeds are also quite shiny if you view them close enough.
Sometimes, you can tell if a seed is good or bad just by looking at it. Here’s how to spot a healthy seed:
- Coloration: A dark coloration with black or gray patches is a sign of a healthy seed. Conversely, white or green seeds are unlikely to germinate because they are not mature. Pale seeds are also more likely to be old and ineffective.
- Waxy coating: Healthy seeds have a waxy, shiny coating. If it doesn’t, then the seed is likely a dud
- Cracks: Cannabis seeds should not be cracked. If your seed has cracks in it, it’s probably best to discard it.
- Shape: The rounder and fatter the seed, the more likely it is to sprout into a healthy plant. Some growers are concerned about large seeds with thick shells but don’t worry. The shell will break down with water.
- Mildew: Grab a magnifying glass and view the seeds close up. A white, dusty powder is a sign of powdered mildew, which means the seeds have a fungus and should not be planted.
In some instances, you can crack the seed open and see inside if you can’t tell anything from the outer shell. An oily inside with a musty smell means that the seed has gone bad. Similarly, black inside the seed means that it’s fermenting. Again, it won’t germinate in this instance.
Method #2: The Touch Test
The feel of cannabis seeds is another good indicator. Hold the seed between your thumb and forefinger and give it a light squeeze. Don’t apply too much pressure – just enough to test its integrity.
If the seed cracks under slight pressure, then it’s unusable. It’s likely to be past its sell-by date.
Strong seeds, however, have a better chance of germinating and growing into a healthy plant.
Method #3: The Water Test
Are you still unsure about your cannabis seeds? You can always do a floating test to see if they’re healthy. By the way, this method works for numerous plant seeds and not just cannabis.
Disclaimer: Don’t perform this test unless you’re ready to germinate the plants right away. The water could damage the seed and ruin a perfectly healthy plant if you dry it out afterward.
For this test, you will need a cup, glass, or bowl of warm water. It should be quite warm, but not hot. It also works best with spring water or distilled water.
Add your seeds to the water, and then wait for 1-2 hours. Those that float on the surface are bad seeds that are unlikely to grow, whereas the seeds that sink are probably healthy.
This method is a great way to check your seeds because it’s low effort. You can also test multiple seeds at once, and it’s really cheap and easy to do.
After you’ve done this test, you need to germinate the healthy seeds. At this point, they will have absorbed water, which can damage the seed if you don’t germinate it at this point. Incidentally, germination is the final test for your seeds.
Method #4: The Germination Test
If all else fails, it’s time to germinate. You might have no idea whether your seeds are healthy but attempting to grow them is an easy final test that will separate good seeds from duds.
There are multiple ways to germinate, including planting the seed directly in soil and seeing if it sprouts. This is a pretty ‘old-school’ method, but sometimes, it works.
More commonly, growers use the paper towel method. Dampen a paper towel, ensuring it isn’t soaking wet. Place this on a kitchen plate and put the seeds on top, then put another plate upside-down on top. A moist, dark, warm environment allows the seeds to sprout. Check on the seeds once a day; after germinating, you should see a white taproot emerge.
At this point, you can transplant the seed into its pot. Use a pair of tweezers and handle each seed carefully, being careful not to touch the taproot. The taproot is fragile and may break if you’re not delicate; furthermore, touching it with your hands may contaminate it.
After germination, you’re good to go. Remember to check back as the plants mature to make sure you haven’t got any male cannabis plants.
Waste not, want not!…
How to Buy Good Cannabis Seeds Every Time
It’s recommended to buy feminized cannabis seeds to eliminate the possibility of males ruining your crop. Even so, some subpar retailers will advertise feminized seeds, only to sell regular cannabis seeds.
It’s vital to buy from a reputable seller that you trust. If this is your first time, read reviews on the seed banks to find out what other customers thought. If lots of buyers were disappointed by low-quality seeds, avoid that company!
Unfortunately, you might still get some bad seeds sometimes. Plants are living beings and can be a bit unpredictable – even the seller might not be aware that some of their seeds are duds. With any luck, the majority of seeds you buy will be healthy and good to go.
The sign of a bad seller is that their seeds are consistently old, dead, and covered in powdery mildew. That said, don’t be too harsh on a seed bank if a couple of their seeds don’t work from time to time when they’re generally reliable.
Final Thoughts on Good and Bad Cannabis Seeds
Telling good and bad cannabis seeds apart is not an exact science. Sadly, you don’t know what’s inside the seed beyond its appearance, so you won’t know what the plant is truly like until you start growing it.
Cultivating marijuana is a bit of a learning curve, so don’t worry if you mess up your crop from time to time. It will only get easier with time.
Hopefully, you can now tell apart some seeds, at least, giving you more opportunities to create a successful grow.
10 Markers of a Quality Marijuana Seed
If you’re looking to start growing your own marijuana, the first place to start is with the seed. What should you look for? How can you tell a good cannabis seed from a dud? Chris Bond tells us.
So, you’ve decided to grow your own marijuana from seed. How do you know if those little, round nuggets in your hand will grow up lush and produce beautiful, productive buds? How do you know if they are duds? While ultimately the genetics will determine the destiny of those little weed seeds, and proper care will help them to realize their full potential, there are some markers you can assess to see if what you have is quality seed, indeed.
What to Look for in a Cannabis Seed
While all cannabis seed is not identical in color, there are some consistencies. Healthy, viable seed will be light to dark brown in color. Seed that is light green or even whitish in color is underdeveloped and should be tossed out. Healthy seed will also have a burled or turtle shell-like pattern on its seed coat.
A quality cannabis seed will have a waxy, protective coating. Seeds that appear dull are probably not as viable and should be avoided if given a choice.
Quality cannabis seed will look like a plump teardrop. Flat or misshapen seeds will not likely produce quality plants.
Quality seed will be firm. Cannabis seed should have a strong seed coat protecting the pre-emerged life inside. Any seed that is tender, pliable or squishy should not be planted; poor results will follow if attempted.
Size is relative, but if you are able to compare several seeds at once, the higher quality seeds are larger. When it comes to seeds, less is more. The fewer seeds that comprise any given amount, an ounce or a gram for example, is generally an indicator of higher quality seeds. The biggest seeds within a species generally have more energy stored within them and have a greater potential to mature into a productive plant. Note that indica strains tend to produce larger seeds than sativa strains so make sure the comparison is made among like seeds.
Weight often goes hand-in-hand with size, but heavier seeds are generally of higher quality than lighter ones. The older a seed gets, the more potential loss of moisture and nutrients, reducing its overall weight. Damaged seed, which has been cracked can potentially lose those same necessary qualities.
#7 Float test
Quality seeds will sink in water. In glass or vessel, place room temperature water deep enough to full cover the volume of seeds to be tested. Place your seed or seeds in the water. After a couple of hours, anything still floating, should not be considered a quality seed. Soaking seeds will allow moisture to cross over the protective membrane and signal the seed that it is time to grow. As such this test should not be performed if the intent is to store the seeds after testing as it may render otherwise quality seed unviable if not meant to be immediately germinated afterwards.
You may not have access to see or have verified information on the storage conditions of seeds, but if you can find this out, it is critical to maintaining quality seeds. While cannabis seeds can be viable for over 10 years in some instances, the best seed in terms of productivity is not more than 12 to 18 months old. It should have been stored in dark, cool and dry conditions to prevent mold or the onset of any fungal issues. Storing in a freezer can prolong seeds as well, essentially suspending time.
#9 Age at harvest
This is another aspect you, the buyer may not be privy to. Quality seed is harvest when fully mature. If seed was collected before the plant was able to load as much stored energy into it as possible, then that seed will be starting out life in a deficit. Color, as referenced above can be an indicator of whether or not a seed was harvested at the appropriate time.
You get what you pay for and a cannabis seed is not exempt from this maxim. Quality seeds are not cheap (at least when compared to other agricultural seeds). This isn’t to say that inferior seeds can’t be overpriced, but if you find cannabis seeds proclaiming excellent genetics for sale at a price that seems too good to be true, caveat emptor.
This is not meant to be a definitive list, as new varieties of cannabis emerge on the scene all the time that may have “normal” traits that would otherwise be viewed as deficiencies in other strains. As always, do your homework, ask other growers who know and buy your seeds from a reputable source.
Dark vs white cannabis seed germination test
One common question from growers is whether white cannabis seeds or dark cannabis seeds have different germination rates. When you compare cannabis seeds you may have noticed that the seeds are rarely identical. Instead you may see a range of different sizes and colours. The differences in size, colour and appearance often produce debate among growers. Why do the cannabis seeds look different and do these differences result in slightly different growth characteristics in the plants which grow from them?
Dark vs white cannabis seeds germination
In the video below you can see a germination comparison. On the left hand side, you can see 9 white Think Different autoflowering seeds. On the right hand side there are 9 dark coloured Think Different seeds.
The autoflower seeds all came from the same batch, meaning that they were produced from the same parent genetics under the same conditions. Seeds were chosen simply on the basis of their appearance. 9 white cannabis seeds and 9 dark coloured Think Different seeds were selected. They were planted in moist (but never soaked) soil and a time lapse video was made.
Note that the white cannabis seeds on the left hand side were the first seeds to germinate, with 8 out of 9 seeds sprouting pretty quickly. In the end all 9 seeds germinated on both sides, which was a 100% score. In terms of white seeds vs dark seeds (cannabis), there was no difference in the germination rates.
Does the colour of your cannabis seeds really matter?
The time lapse video shows that the colour of your cannabis seeds doesn’t have any impact on their germination rates. The colour of the shell casing is simply not an indication of the type of genetics contained inside. Nor is the colour or appearance of the exterior of the cannabis seed a good indicator of any other property, such as the future plant sex, size or potency. Only the genetic material inside the cannabis seed really determines the types of result that you can expect.
Black cannabis seeds germination test results
The dark cannabis seeds (on the right hand side in the video) showed the same germination rate as the white cannabis seeds (left hand side). However, the white cannabis seeds appeared to germinate a little bit faster than the dark cannabis seeds.
White cannabis seeds germination test results
Can white cannabis seeds germinate? One curious result from the white vs dark seeds cannabis video was that the white cannabis seeds appeared to germinate slightly faster than the dark cannabis seeds. This is interesting, since the seeds all contain the same Think Different autoflowering genetics from a recent cannabis seed batch.
One suggestion is that the white cannabis seeds may have a slightly softer shell, allowing the white cannabis seeds a slightly faster germination. The experiment was repeated twice more. On each occasion, the seed germination rates were the same, but the white seeds tended to germinate faster.
|The best ways to germinate cannabis seeds|
Why are some cannabis seeds white and some black?
Even cannabis seeds produced from the same branch of a plant can have quite different appearances. Size, as well as shape and colour can vary. Some cannabis strains can produce seeds that have certain appearance characteristics. White Widow seeds, for example, can often be very small and pale. Frisian Dew seeds can have a slightly grey colour.
There have been many theories about how the size, shape and colour of cannabis seeds can affect the plants which they eventually produce. In reality, it’s the cannabis genetics inside the seed case which really determines the results that you can expect. The shell of the seed and the markings on it are purely cosmetic and don’t give any clues to the results you can expect.
In the years before Dutch Passion invented feminised cannabis seeds, people would often try to predict which seeds would produce female plants. Of course, this was impossible. But it didn’t stop people going to great lengths, even measuring the weight of individual seeds in an attempt to derive some knowledge from the seeds physical appearance/size.
|What does the appearance of cannabis seeds indicate?|
Is the colour of seeds a cosmetic difference only?
Some dark cannabis seeds have black lines on them (tiger prints), giving them a distinctive appearance. Other seeds have no significant patterns or markings on them at all. Dark black cannabis seeds can be occasionally seen.
You may also see light vs dark cannabis seeds produced from the same plant. But it’s important to note that cosmetic differences between the seed casing is not a factor which defines how the cannabis seeds grow or germinate.
The genetic material in the soft plant tissue inside the seeds is what really determines the type, size, sex and potency of the cannabis you will eventually grow. These genetics, along with the environment you provide, will control the terpenes, cannabinoids, yield and potency of your eventual cannabis harvest.
Why are some cannabis seeds white and some black? It’s just the way that nature has evolved. Seeds from all kinds of plants and trees show similar variations in their appearance.
What should you look out for in a cannabis seed?
Rather than looking at the appearance of a cannabis seed, you should focus more on the quality of breeding which has gone into the seed. Some growers think that only the largest, tiger-striped cannabis seeds will go on to produce the best plants. Yet some strains will never produce seeds like that.
Time spent researching your cannabis seeds and cannabis seed supplier is time wisely spent. Look for a seed supplier with a good track record in cannabis breeding. Preferably look for a cannabis seed supplier that has been around for a long time with a few cannabis cups and plenty of online reference grows for you to check out before you spend your cash.
Knowing whether you prefer e.g. a Kush, a THC rich vs CBD rich strain, a fruity strain or a Skunk strain is a good place to start. If the array of cannabis seed choices can seem overwhelming, the following article may help you select the best strain for you.
|How to choose the best cannabis strains for you|
Once you have the best cannabis seeds for you, it’s worth ensuring you get maximum germination rates with a good germination method. The preferred Dutch Passion way to germinate cannabis seeds is with moist (but never soaked) cotton pads. If you spot any issue during the growth of your cannabis seeds, we highly recommend to refer to our illustrated guide featuring the key nutrient deficiencies and excesses symptoms and how to cure them.
White cannabis seeds vs dark cannabis seeds
We hope the germination video is a useful illustration of the fact that there is little useful information that can be conveyed by the colour or darkness of a cannabis seed.
Each cannabis strain can produce subtle differences in the size and appearance of their cannabis seeds. You can even expect to see differences between cannabis seeds produced from the same plant. Don’t worry about trying to read too much into cannabis seed appearance. Instead, do your research carefully and select the best cannabis seeds for your particular needs and your specific grow situation. Enjoy growing and good luck!