In a life or death situation, surgery may be the only option. Meaning—only do this if nothing else has worked because this technique ruins as many seeds as it saves.
If you’re going to keep seeds more than a year or two, proper storage will dramatically increase the chances of late-stage germination. Place them in an airtight container. Put the container in a refrigerator set at 6–8°C with 20–30% relative humidity. If excess moisture is a concern, add silica gel packs to the container.
As you proceed through these steps, the risk of damaging your seeds past the point of recovery increases. Between each suggestion, give them a few days to a week to germinate. Allow the outside to dry each time to prevent rot. Do not try all or multiple techniques at once.
4. SLICE THE SEED
As cannabis seeds age, their protective outer shell hardens and prevents water from passing through. Unless the tiny, dormant embryo that lives inside the shell detects moisture, it doesn’t know that the conditions are right to sprout. As a first step, pre-soak your old cannabis seeds for about 12 hours to see if that does the trick.
Removing the ridge not only makes it easier for the seed to open, it helps with water absorption.
The seed’s shell is made up of two pieces, with a seam going all around. The side that’s raised more than the other is the ridge. A hardened ridge can make it difficult for the seed to open. To remove the ridge, run a sharp blade along the ridge on both sides. Handle gently and it should come off without damaging the inside of the seed.
To scarify your seeds, line a matchbox or other small container with sandpaper. Drop the seeds inside, shake vigorously for 30–60 seconds, then remove. You may not notice much of a difference, but the small micro-abrasions are sometimes enough to let water breach the shell and trigger germination.
Germinating old seeds can be difficult, if not impossible, if it’s not done exactly right. That being said, it is possible. So before you toss those marijuana seeds that you’ve been keeping at the bottom of an old baggie, be sure and give this a read. But, let’s just start with how to store seeds the right way, so you won’t have to bust out those superpowers next time.
Okay, so maybe you didn’t have that information on hand when you scored your last round of seeds. Not to worry, there are quite a few clever, science backed tricks that you can employ to revive your little glory bombs. The problem with most old seeds, whether stored properly or not, is that as the seeds ages, it’s shell hardens. This makes it extremely difficult for water to get inside the seed to help your little seedlings grow and emerge. The best ways to reinvigorate old seeds is to find clever ways of penetrating their heavy duty shells.
You might find yourself asking “How long do marijuana seeds last?” This is a great question, and the answer almost solely depends on the methods of preservation. Depending on how you’ve stored your seeds, they can essentially last indefinitely.
This is a pretty common practice used to germinate almost any seed. Take a few moist paper towels and place the seeds you’d like to germinate on top. Place a few more moist towels on top of the seeds and seal in a container. Keep the container somewhere it will be warm and get a bit of light. Seeds should germinate in about 72 hours.
As they say, not all heroes wear capes, and absolutely zero of them toss old seeds.