After days of searching, you finally found a reputable, secure, and highly-rated place to buy cannabis seeds online. Hopefully, your Google search led you to Growers Choice Seeds—one of the top seed banks in the US and Canada. Let’s say you purchased some seeds and now you eagerly run to the mailbox each day, heart all a-flutter, waiting for that magical package to arrive. And then suddenly, wonder of wonders…you receive a notification that your cannabis seeds have arrived. “But what if I don’t want to start growing right away? Can I save my seeds for later? And if so, how do I keep them fresh?” That’s what today’s post is all about.
For one reason or another, you can’t germinate your cannabis seeds right away and begin the growing process. Perhaps you still need to set up your grow space/grow room. Or, maybe, you’re planning ahead for when your current crop is harvested. After all, timing really is everything when it comes to keeping your cannabis seeds fresh. Rest assured that your seeds will be ready to sprout whenever you’re ready for them—as long as you stick to a few simple storage tips.
The Ideal Storage Methods
Planting your seeds as soon as possible will only improve your odds of successful germination, but that doesn’t mean you can’t keep them viable for a long time—up to five years, and possibly longer. Some have reported seeds remaining viable for more than a decade! Before contemplating your seed storage options you’ll want to consider how long you plan to be putting them away. This will help you optimize your storage choice and stick with it. Cannabis seeds don’t take kindly to many variations in temperature, so it’s best to be decisive and leave them alone until planting time.
The fundamental rule to follow is this: Seeds should be kept somewhere cool, dark, and dry. The ideal temperature is around 40 degrees Fahrenheit (or 5 degrees Celsius), and the ideal humidity is around 9%. You don’t want them getting too warm or too moist, lest they begin sprouting prematurely. If you’re just putting them away for a few weeks, a dark drawer or cabinet should be fine, provided the room it’s in doesn’t get too warm. (Let’s all take a moment to be thankful for the wonder of air conditioning.)
If however, you need to keep your seeds healthy longer-term, most experts recommend the refrigerator. You can empty out one of those produce drawers and create a seed repository—especially if it’s one that lets you dial the humidity down. It’ll keep them at the most consistent temperature, and protect them from excess moisture.
The Rice Trick For High Moisture
Since moisture is the enemy of effective seed storage, you want to keep the humidity as low as possible. To that end, some growers like to toss in a silica gel desiccant packet along with their seeds while they’re in storage. Silica packets are those little pillow-shaped things you sometimes find in vitamin bottles, where they’re used for the same reason: To absorb moisture. Don’t have any silica gel desiccant handy? You might also try tossing in a few dozen grains of uncooked rice.
Pros And Cons Of The Freezer Method
Freezer storage is a real point of contention among growers. Some say it can hold seeds in stasis, extending their lifespan, while others are adamant that too much cold will damage them just like heat will. This is one where you’ll have to read up and decide for yourself since right now there’s no consensus to be found, but I personally think the fridge is a safer bet.
Wherever you keep your seeds, you should seal them in a plastic bag and another external airtight container. A film canister is ideal since it’ll also protect them from light. If you can’t get your hands on one of those (who uses film these days?) a mason jar will work too, as long as you keep it somewhere dark. Make sure the jar is completely dry inside and out before you seal it up; the point is to avoid water as much as possible. And don’t forget to label your strains, so you’ll know what you’re growing!
Most Importantly, Handle With Care
When taking your seeds in or out of storage, here’s an important tip: Try to touch the seeds as little as possible with your hands—preferably not at all. Oils from your skin can start to wear away the seeds’ protective outer shell, exposing the organs within to oxidation. The best practice is to use a pair of tweezers to (gently) handle the seeds when needed.
You needn’t take all the precautions they use at the Svalbard Global Seed Vault in Norway. Not everyone can store their seeds 400 feet deep into a sandstone mountain (which, let’s face it, isn’t all that convenient). Just remember the mantra “cool, dark, dry” and your little treasures should be fine. And when you’re ready to take the seeds out of storage and get growing, head on over to our comprehensive germination guide for the best techniques.