If you’re storing your seeds for the short term (a couple of weeks or months), a standard mailing envelope or a tan coin envelope will do in a pinch. If the envelope paper is thick enough, it will protect the seeds from the most harmful ambient light. If the envelope is stored in a cool, dry, dark, and temperature-stable spot like the back of a closet or a drawer, the seeds should also stay dormant in the short term. Plus, an envelope makes it easy to Sharpie the name of the strain, the date of storage, and any other important notes you have. If you want to be extra safe about it, throw some grains of rice or a desiccant pack in there to regulate the humidity.
Whatever the reason, you need to be sure those cannabis seeds stay viable in the long term. Properly stored seeds can last for up to five years and still remain viable, and some strains have been reported sprouting at ten years or more. However, proper storage is not as easy as it seems, since seeds are looking for any excuse to start sprouting and there are a number of factors that tell the seeds that the time is right to stretch out their roots and branches. Store your seeds in the wrong conditions and they might end up dead, rotting, or diseased by the time you’re ready to introduce them to the soil.
Humidity is another enemy in your battle for long-term storage because any hint of moisture is another clue to the seed that it’s time to stretch its leafy arms and legs. If the seed shell breaches before it’s in the soil, rot can set in.
Besides being dark, you want to expose your seeds to as little oxygen and carbon dioxide as possible. These gases are what growing plants breathe, as well as the pests that consume them. If you’re refrigerating your seeds, make your container as airtight as possible. If you have some vacuum-sealed plastic on hand, even better.
Unlike a mailing envelope, glass jars are airtight which makes them much more suitable for long-term cannabis seed storage. Because many types of plastic can let small amounts of water in overtime, it’s highly recommended that you use glass with rubber stoppers. When storing seeds long term, you should also throw in a desiccant pack to keep the humidity stable.
Of course, this method is only as good at the stability of your home’s climate. If you live in a humid area prone to frequent storms or weather fluctuations like Florida, envelopes will only get you so far without ruining your seeds.
First, let’s go over the five main factors to consider when it comes to storing your cannabis seeds, especially for the long term.
You’ve received a package of your favorite high-quality 10 seeds (from us). You’ve planted 5 of them for this season and are waiting to plant the next 5. What do you do? Store them. After all, proper storage is an essential part of being a good grower. Here’s why:
Store them incorrectly, however, and you run the risk of spoiling your entire growing season. Seeds can die, be damaged, or simply lose their efficacy if stored poorly.
1. Gather materials
All great cannabis plants begin with quality seeds. Unfortunately, many growers overlook the simple fact that seeds are living organisms that need preserving to remain in tip-top condition. Store your seeds in haphazard ways, and you run the risk of affecting both quality and germination. Luckily, proper storage is easy to do as long as you know how.
If you’re storing your seeds in a humid, improperly sealed environment with access to moisture, your seeds may rot, mold or prematurely germinate. Once water comes into contact with a seed, it produces ethylene and begins to germinate. Even just a little droplet can cause harmful mildew that can kill your seeds. Aim for an environment of 10 to 20% humidity and use a desiccant. Seeds can begin to germinate at just 40% humidity.
Labelling your seeds is crucial. This will stop you from opening your containers to check them and will provide details on both strain type and date of purchase. You can write all this simply on a small paper label and place it on the container’s exterior. Dates will ensure you can plant for freshness.
When you’re ready to germinate your seeds, inspect them and germinate any seeds with damage to the outer shell first. The outer shell of your seeds is designed to protect the volatile genetics inside. Seeds with cracks in the outer shell are a lot more vulnerable and shouldn’t be stored.
Remember, modern fridges are very dry. It’s super important your seeds aren’t directly exposed to these conditions, as the lack of humidity can cause them to use up their nutrient stores just to stay alive.
If your seeds get exposed to light or rapid changes in temperature, these conditions will trigger them to use up their nutrient stores before they ever see soil, meaning they won’t have the nutrients they need to germinate. High humidity, on the other hand, can trigger fungi to grow on your seeds.
WHERE AND HOW TO STORE YOUR CANNABIS SEEDS
Older seeds often have an extra tough outer shell. Gently scratching this shell with some sandpaper can help moisture and warmth enter your seed at the time of germination. Try gently scarring your old cannabis seeds just before soaking to help them sprout.
Ideally, you want to store your seeds in a cool, dark, and dry place. Whenever possible, keep your seeds in their original packaging. At Royal Queen Seeds, we’ve specially designed our packaging to protect our seeds until you’re ready to plant them.
Ziplock bags, for example, are great because you can remove all the air from them to create an almost vacuum-sealed container for your seeds. Once vacuum-sealed, put your bag inside a dark plastic bag or dark container to protect your seeds from your fridge light.
Before germinating your old seeds, try soaking them in carbonated water enriched with fulvic acid, germination booster, hydrogen peroxide, or gibberellic acid. For best results, use room temperature water and soak your seeds for 12 hours in a dark place.