Seeds carry on life processes, at a low rate, whilst dormant. Moisture they absorb from the air combines with stored nourishment within the seed to form a soluble food, which then combines with oxygen from the air to release water and heat. Too much moisture in the air will cause the seed to burn up its stored food too quickly producing excess heat which will further lower the seeds ability to germinate. The need is to keep these exchanges to a minimum during storage to prolong life in the seed.
A freezer is best for long-term storage of seeds although you need to make sure:
6-9% moisture is ideal for long term storage of hemp seeds. A test for moisture levels shows that hard shelled seeds like hemp seeds shatter instead of mashing at around 8% moisture when placed on concrete and struck with a hammer.
Silica gel, often used in the drying of seeds, can also be used to help maintain stable moisture levels within a permanent storage container. Equal weights of silica gel to seed are used. In general hemp seeds weigh between 0.01 and 0.02 grams and our silica gel sachets contain 0.5g. We recommend seeds are kept in aluminium zip-lock bags and stored inside seed jars along with the correct amount of silica gel to maintain low moisture levels. Be aware that you can seriously damage seeds by reducing moisture levels too much, so do not use too much dessicant. Silica gel, aluminium zip-lock bags and seed jars are all available to buy from our Seed Storage section.
Similar to moisture and temperature, light can help stimulate and support the germination process. And, just as many foods, pharmaceuticals and chemicals rapidly deteriorate when exposed to light, so also is seed viability and vigour affected by being exposed to light during storage.
It would help if you also stored your seeds as high above the ground as possible. This reduces the possibility of a pest like a rodent coming in and feasting on the seeds.
If you have old seeds not stored in ideal conditions, there are still a few ways to germinate them.
If you only require short-term storage, a dark drawer or cupboard is sufficient. The most important thing, regardless of the duration of storage, is to avoid temperature and humidity fluctuations. Rapid variations in temperature, in particular, can destroy your seeds. If you live in a location with warm daytime temperatures and cold nights, avoid outside storage.
A Note on Insects & Pests
Insects and pests also thrive in dirty storage areas. As a result, you must ensure the storage area remains clean. Otherwise, you won’t just attract pests to your seeds; microbes will form and damage the seeds. Do you want to consume marijuana from contaminated seeds?
If you purchase marijuana seeds and intend to use them almost immediately, you should have no issues. Even so, it is probably best to keep them away from direct light. In the short-term, a dark cupboard is sufficient as long as the temperature and humidity are reasonable.
Here is a quick overview of what will likely happen to cannabis seeds at different humidity levels:
If you don’t begin with great seeds, you can forget about producing a harvest of high-quality marijuana. A lot of growers seem to forget one simple fact: Your seeds are alive! Although cannabis seeds are fairly durable, improper storage can ruin them. If you’re paying $10-$20 a seed, losing a full batch is an expensive mistake.