When you begin to cultivate cannabis, you soon realize that not all seeds are planted during the season you buy them. There will be times when you decide not to plant all of your gg#4 seeds or blue dream weed seeds, or you may have collected seeds from the current harvest and want to use them in the future. In these cases, the seeds need to be stored.
Marijuana seeds can survive storage very well, but it is vital to protect them against enemies like moisture, light, and temperature changes. When seeds aren’t stored correctly, crops produced from them are more susceptible to environmental hazards, and some seeds won’t grow at all. Proper storage is crucial for healthy future plants.
Seeds Are Living Organisms
Cannabis seeds are generally hearty and have tough outer shells. Seeds can withstand a lot of conditions, but they are not indestructible. High humidity and quick temperature changes, for example, can ruin seeds.
Seeds are alive but dormant. They are resting the way some animals hibernate. Because seeds can die before they germinate, it is crucial to protect them during storage.
Decide Which Seeds to Store
The seeds you buy from a seed bank are typically in good condition and usually arrive in protective packaging. If you do not plant all of them immediately, they are safe to store unless they have been damaged.
The outer shell of your seeds is designed to protect the volatile genetics inside. Seeds with cracks in the out shell are a lot more vulnerable and should not be stored.
Be especially careful with harvested seeds, which can include imperfections. It is essential to identify any with cracked shells. You should germinate or plant them right away since they will not store well.
For optimal storage results, use the freshest seeds you can, because they have the best chance of successful germination.
Prepare Seeds for Storage
It is essential to dry seeds before storing them, but you do not want a 0% moisture level that would kill seeds. A 2%-3% moisture percentage is best for seeds that are ripening and drying. During this process, they stop or slow most physiological processes to prepare for dormancy.
Become Familiar with Cannabis Seed Enemies
Stored cannabis seeds must be protected against humidity, light, and temperature changes, which are their natural enemies.
Humidity and temperature are the most critical factors that impact seed quality during storage. Humidity is the most important. Cannabis seeds such as og kush feminized seeds and sour diesel weed seeds absorb moisture from wet environments and will dry out when they are in dry atmospheres. You can double seed storage life with every 1% decrease in moisture.
Humidity impacts seeds in the following ways:
- Humidity levels of 80–100% cause seeds to drown and wilt within 12 hours.
- Humidity levels of 40-60% cause seeds to start germinating.
- Humidity levels of 18-20% can lead to heat that causes seeds to sweat.
- Humidity levels of 12-14% will create a perfect breeding ground for fungi.
- Humidity levels of 8–9% can cause insects to become active.
It is also essential that stored seeds are not exposed to light because it will cause them to begin sprouting. The easiest way to avoid the problem is to ensure storage containers and outer environments are dark.
A storage environment must protect seeds from temperature fluctuations that can lead to seed decline. Expert growers recommend keeping stored seeds as close to 40ºF as possible.
Professional Jorge Cervantes recommends ensuring humidity is below 5% and keeping temperatures at 35-40ºF.
When you are preparing for storage, be aware of oxygen concentrations. Lowering oxygen exposure reduces or prevents seed respiration during storage, and that deters germination. From Indica strains like Purple Kush to Sativa strains such as
Choosing Storage Containers for Seeds
When seeds are placed in an airtight container that protects them from environmental hazards, they will remain viable during storage.
You can store your leftover seeds in the package provided by your supplier. The protective packaging used by most seed banks is ideal for short-term storage.
Glass jars with airtight lids (such as Mason Jars) are the best choice for all storage needs. Traditional black film canisters work well, too, but it can be hard to find them now that most people take photos with cameras.
Some people put seeds in plastic containers, but that is not an ideal solution. Plastic has tiny pores that let air get into containers and harm weed seeds.
Containers made of a single material create a better environment than those that use two. For example, a glass jar might have a plastic lid, and each element will react differently to temperatures. That can expose seeds to less than favorable conditions.
When possible, it is best to use opaque containers since they shield seeds from the light. If you have to use clear glass, put seeds in something opaque, like black plastic wrap, and then place them in containers.
Desiccants Are the Key to Moisture Control
You will also need to add a desiccant to storage containers. Desiccants are substances that help create a state of dryness by drawing out water. For example, silica gel packs are commonly added to commercial packaging to keep contents dry.
During storage, a desiccant can maintain 2-3% moisture levels inside an airtight container. Desiccants also extend seed life by absorbing the ethylene produced naturally as part of the aging process.
You can usually find gel packs at stores like Walmart or florist shops. Even uncooked rice will do. Gel packs are reusable, but you have to replace rice periodically. It’s a good idea to create a protective barrier by placing a material like cotton wool between seeds and gel desiccants.
Commercial growers agree that that most marijuana seeds, such as the ak47 strain and lemon haze strain can last up to two years if they are stored in a cool, dark place. Most survive as long as five years when they are stored well.
Storing Seeds Short Term
It is relatively simple to store healthy cannabis seeds for days, weeks, or months without harming them.
Pot seeds placed in airtight containers can be safely kept in any cool, dark area with controlled humidity. Household cupboards serve well as long as they are protected from temperature changes. Avoid outdoor sheds or garages if daytime and nighttime temperatures in your area fluctuate a lot.
Preparing for Long-Term Storage
If you intend to store seeds for longer than a few months, heat-sealable or vacuum-sealable containers are ideal. Glass Mason Jars work well in the long term because they are protective and reusable.
In addition to guarding seeds against light, moisture, and oxygen, your goal is to slow the seed’s life cycle to a minimum and prevent aging. Correct storage also stops germination.
The best atmosphere for long-term storage is cold and dark and dry. Keeping seeds cool helps stop them from drying out entirely and prevents any bacteria from activating. The simplest solution is to put sealed storage containers in the refrigerator.
If you decide to refrigerate your seeds, put them in at the back to minimize the impact of temperature changes when the door is opened and closed. You may even want to keep them in a separate refrigerator that you rarely open.
To Freeze or Not to Freeze?
Some marijuana authorities recommend freezing seeds that will be stored for more than a year. Others think that placing seeds in airtight containers in the refrigerator or other cool dark spaces is enough to keep them safe long-term.
A general rule of thumb is that the lower the temperature, the slower seeds decline, although some professionals argue that extreme temperatures may damage seed cells.
If you freeze your seeds, try not to defrost them more than once. The more often they are defrosted, the smaller the chance seeds have of germinating. A single defrosting should not harm them, however.
Carefully stored cannabis seeds routinely stay viable for five years or longer. After five years, their germination rates drop. Nevertheless, plenty of people have successfully grown crops from seeds that were ten or more years old.
Tips for Germinating Stored Seeds
Cannabis seeds that are correctly stored for short periods generally sprout without problems. However, germinating seeds that have been stored for years can sometimes be a problem since older seeds have harder shells.
Professionals suggest placing older seeds in a glass of water containing a few drops of hydrogen peroxide and then letting them sit for twenty-four hours. The process helps the embryo develop. Hydrogen peroxide
softens the shell and encourages water infiltration.
Water should be around 71.5°F (22°C), or room temperature. Gently scarring the shells with sandpaper will allow moisture and warmth to enter.
You can also facilitate germination by carefully removing the shell’s ridge using a sharp Stanley blade. If all else fails, make a tiny cut in the shell. Be aware that cutting the shell is tricky and can damage the seed.
There are times when every cannabis grower has more seeds than they can plant. Fortunately, cannabis seeds can be stored for years and will still germinate. The key is to store seeds in airtight containers that protect them from light, humidity, and temperature changes. Containers may be placed in cool, dark areas that include refrigerators and freezers.