Marijuana seeds should be kept in a cool, dark place such as a basement or in your refrigerator. They should be in an air-tight container and must stay dry. Putting a cotton ball in with the seeds before storage can help suck up any extra moisture (this is why you often see little bits of cotton in seed breeder packs).
Heat and moisture ‘signal’ to cannabis seeds that it’s time to sprout, so as long as you keep the seeds in a dry, dark environment they can remain viable for years. I have heard cases of seeds sprouting after being in storage for 5 or even 10 years. However, you will notice that older seeds take longer to germinate than fresh seeds and a few of them may not sprout at all. As time goes on, fewer and fewer of the seeds will successfully germinate.
Bag seeds you randomly find in your buds aren’t supposed to be there, so that means that the genetics are a toss-up. Even if the seeds started with good parents, there’s no telling how high or low the quality will be. Unfortunately, the only way to find out is to grow it… Some growers win the genetic lottery, but many others lose out.
Note: Although the hardiness of the seed was likely important in the wild, cannabis growers have been breeding plants for generations to make good buds, not seeds! We growers strive to provide an ideal germination environment that lets almost any seed germinate successfully. As a result, we haven’t been breeding for seed hardness. Just like a teacup poodle hasn’t been bred to be strong, cannabis seeds haven’t been bred to be strong. They have other qualities we love 🙂
Seeds are a little nugget of genetic material than can hopefully grow into a plant. And like all other genetic material, it doesn’t last forever! Although seeds can be viable for quite years and years after they’re first produced, the chances of them successfully germinating goes down over time (and old seeds also tend to take a lot longer to germinate than fresh ones). The resulting seedlings are also more likely to be slow growing. But sometimes they sprout like they were born yesterday!
So I’m a big believer in the fact that if you put the seed in the ground and a fast-growing healthy seedling comes out of it, it was a viable seed! Don’t toss a seed you are really interested in just because it’s a little pale; give it a chance (I’m talking more about tan seeds, it’s very unlikely a yellow seed will sprout)!
Bag seeds are a wildcard! You never know what you’ll end up with!
Check out the picture below. We sprouted all the plants at the same time. The tub on the right has seeds that were planted within a week of receiving them in the mail. The tub on the left has a very popular strain with award-winning genetics… but the seeds were more than 6 years old from when we first bought them. Even though they were all put into the tank at the same time and the new seeds grew like crazy, the seeds on the left got outpaced by algae – only one sprouted and though its roots keep growing and growing the actual never got any bigger than two round leaves even after a month!
That being said, sometimes bagseed is all you have, and lots of growers get lucky!