Do marijuana seeds go bad? What to know before you grows (2025)

Can marijuana seeds go bad? Of course, they can! All seeds go bad; their shelf life is not infinite. Marijuana seeds need to be properly stored, totally protected from moisture, humidity, oxygen, and light, if you want the maximum lifespan.

If you’re new to cultivating cannabis, you need to know how to identify a good seed from a bad seed and how to properly store your marijuana seeds. Unless you want to learn the hard way, here are the basics behind how long marijuana seeds last and how to make sure you don’t waste time and money on common mistakes.

How long do cannabis seeds last?

As you go further into your journey as a grower, you’ll learn that every seed is different. Even individual seeds of the same strain can have different lifespans, and certain types of cannabis seeds have longer lifespans than others. For example, feminized seeds don’t typically hold up as long as regular seeds and autoflowering seeds generally last the longest when properly stored.

The majority of cannabis seeds, provided they are stored properly, can last on average about two to five years with varying expiration dates. There’s no real set expiration date. When we’re talking about how long they last, what we’re really discussing is how long they are viable.

A non-viable seed is one that does not germinate, even when given optimal growing conditions, and even when it is non-dormant, according to this rad book: In Viability of Seeds ed. E.H. Roberts (a useful addition to any grower’s library).

Although it’s possible to ‘revive’ older marijuana seeds and get them to germinate, most experienced growers will tell you to try and use seeds that are one year old or less to maintain quality and yield.

What causes marijuana seeds to go bad?

Age

If you properly store your seeds and find them non-viable years later, they may have simply died of old age. Remember that a cannabis seed’s viability, aka ability to germinate, decreases with age, even in optimal storing conditions. Different cannabis cultivars will have different natural seed lifespans, and there’s no definitive expiration date you can go by.

Genetics

The longevity of cannabis seeds is also determined by their genetics, specifically in relation to dormancy. For example, seeds like weed with natural dormancy mechanisms have been found to last years longer than their counterparts. When a cannabis seed goes dormant, they are protected from germinating under unfavorable conditions but can continue to stay alive for years or even decades if in the soil.

Improper storage (temperature, moisture, oxygen, light)

According to the studies referenced in Roberts’ book on seed viability, the top three factors that cause seeds to become non-viable are temperature, moisture content, and oxygen level.

Scientific research has shown over and over again that lower temperatures and lower moisture content increase the viability of seeds in general. For example, this study found that as storage time increases, seeds need to keep moisture content between 20% and 30% to maintain viability.

If you’re new to growing your own weed and your seeds go bad, it’s probably because you’re not storing them correctly. As with all seeds, unfavorable temperatures, humidity levels, oxygen levels, and exposure to light can decrease the shelf-life of cannabis seeds. They should be stored in a cool, dark, dry place, protected from moisture and oxygen.

What to look for: How to know when a cannabis seed has gone bad

If you want to know if a cannabis seed has gone bad, primarily look out for color, shape, and sheen. The color should be amber to dark brown, but not too dark. Bad seeds can often appear strikingly dark in color, even black as night or burnt, which is a surefire sign they won’t be of any use.

Number two, if the seed is flat, that’s also an indication it’s not viable; the shape should be more puffed out and a bit round like an oval. You’ll typically see flat seeds when they’ve completely dried out from age or exposure to heat.

Finally, viable cannabis seeds have a little waxy sheen on their coating. If you find that your seeds look especially dry or brittle, with not even a smidge of that translucent coating, they’ve probably gone bad.

How to increase shelf-life aka how to properly store cannabis seeds

In short, as with all seeds, lower temperatures and low humidity are the prime storage conditions for cannabis seeds of all types.

Check out the following tips that experienced growers use to get the most shelf-life out of their marijuana seeds:

Store your seeds in a refrigerator or freezer.

Remember that to help marijuana seeds last longer, they need to be protected from moisture, oxygen, hot temperatures, and light. A refrigerator or freezer checks all these boxes. Go a step further by turning off the automatic light, so that the light bulb doesn’t come on every time the door is opened. If you live in a cooler climate, you can get away with storing your cannabis seeds in the back of an oft-used drawer or closet, but the fridge/freezer is more foolproof.

Vacuum seal + airtight container

To increase longevity, first vacuum seal your cannabis seeds and then place them in an airtight container. If you don’t use a vacuum seal, use a ziplock bag with all the air pressed out. Then, place the secured seeds into an airtight container, like a jar or piece of tupperware.

Put rice or silica gel inside

Before you seal the lid on the airtight container, add some rice or silica gel next to the bag of seeds. This is just a little extra protection from moisture that costs practically nothing.

Label your seeds

Label your seeds with date and strain info to prevent confusion later on. Not to mention, many growers will tell you that at one point or another, a family member, a friend, or someone else entirely has accidentally thrown away viable cannabis seeds thinking they’re trash. To prevent any miscommunication, label your seeds so that everyone who sees them knows not to mess with them. Hands off people.

Proper storage is the name of the game

Cannabis seeds can stay viable for years if they are stored in an area that protects them from light, heat, humidity, and oxygen. In sum, proper storage of cannabis seeds is the name of the game, and failure to do so is the main reason they go bad. However, age and genetics also play a role in the longevity of cannabis seeds. You can tell if a cannabis seed has done badly by its darker color, flatter shape, and overall drier, more brittle appearance.

To optimize your storage conditions and increase the shelf-life of your marijuana seeds, the best place to put them is the refrigerator or freezer. If you can’t do that, be sure the area you select is cool, dry, and dark. Next, place them in an airtight bag (preferably vacuum sealed), and put that inside an airtight container with rice or silica gel. And don’t forget to label your seeds. Happy growing!