i had seeds stored outside in my garage (sensi black domina + the freebies) for 7 years and they went through temperature extremes +40 to -40 and none of them germinated after, 30+ seeds
3 Likes
exposure to moisture is what kills the seeds, not being frozen IMO. I’ve read that freezing is best for very long-term storage where the seeds are not taken in & out of the cooler often. Leave those in the refrigerator instead.
I’ve stored them in the fridge in a glass jar with silicon dessicant to lower the humidity. So far getting near 100% germination after 15 years.
11 Likes
Heat will also do them in, especially if it is humid. You want to keep them cold and dry. According to the book, Marijuana Potency, the colder the temps, the less influence is moisture and humidity on seed decline. It also states that above 50F that Cannabis seeds will show a marked decline in germination rates, even in sealed jars, and decline markedly in about 2 years and likely be sterile in 4 years. Here in the wild west, dry is not as big an issue. In the US South, or even the Midwest and Northeast in summer where it is extremely humid, that is likely a bigger issue.
I put about one rice grain in per MJ seed. 1:1 is pretty easy, but you can err either way. You do not need to drown the seeds in rice. You can also use the little silica gel desiccant bags with them. They come in things like vitamin pill bottles and the like to keep them dry. I use bulk converted white rice.
yes or the silica cat litter will work good too i think, i save all those silica packs now for reuse 
1 Like
Continuing discussion from Huge cache of seeds left behind, what to do?
These seeds should be 1) packed and frozen for long term storage and 2) stored in a seed bank someplace safe. But then the question is by whom and where. There are so many…
I agree… it’s cold in Upstate New York now… I have them in a spare room that’s about 50 degrees Fahrenheit all the time… While cataloging them I didn’t want to take them in and out of the refrigerator because of temperature fluctuations. I hesitate to put them in the freezer because of that as well. What is your opinion?
2 Likes
I was reading from this site that someone had stored his seeds without Refrigeration in a fishing bait box… And they popped
I agree that they should be kept cool at all times
1 Like
I keep mine in small glass jars, in the shade, at room temp.
Some believe in refrigeration.
I don’t expect to get more than 3-5 years shelf life out of them. But I wouldn’t be shocked if they last longer.
2 Likes
I agree with freezing if long-term storage… 10 years plus… Otherwise Refrigeration is probably prudent… But I agree… They are seeds and if kept at cool temperature… Most will pop 
1 Like
If they have been kept in a freezer or refrigerator for a long period of time I would think it would be best to keep them that way. I’m no expert but I would think that if they were frozen for a long period that it would be bad for them to go from frozen to room temps and vise versa you should keep them as they have been kept .
At this point if it has been out of the fridge for a while then I don’t know… Hopefully someone with more experience will chime in. I just keep mine at room temp but I don’t have a large collection and do not intend on keeping them for years as they will be popped within 2 years I am not worried about long term storage myself… I think the main issue is whether they were frozen or just refrigerated. If just refrigerated I would say just put them back in the fridge and keep them there. I think if they are frozen then thawed and then frozen and then thawed it would be problematic for sure…
1 Like
50 deg F is too warm. In studies done, at 50-60 deg F, 50% of seeds will typically go off in 2 years, and upward of 100% will go off in 4 years. Humidity is also a bigger factor the warmer the seeds are kept. The colder they are, the less impact that humidity has. Standard US freezers are 0F, which is a good temp to keep them at. A no-defrost deep freezer is best, but I have kept them in frost-free freezers as well with good results.
My advice, take photos of them all and get them frozen. Sort out catalog details later. Time is critical. You do not know how long they have been around, and the longer they stay this warm the more that will go off. And as I do here, when it is below freezing outside, you can take them outside on a porch and paw through them. Freezing and defrosting is not that big an issue either. Mine have been frozen and thawed many times over. Most are still viable. The amount of TIME that they are warm seems to be the biggest factor in seed death, and humidity will accelerate that if kept above freezing. For that reason I do not recommend a refrigerator. If you have to, use sealed jars in a refer and rice or dry bags to keep them DRY.
3 Likes
I will take your advice… They are all in their individual bags of rice now… Going into the refrigerator
5 Likes
I have seeds that are viable after 40+ years now. I have moved up and down the west coast of the US and taken my seeds with me from freezer to freezer, thawing for days or ever weeks between. While it seems intuitive that they remain at some stable temp (many people claim that is better), that does not seem to be a big factor in long term storage of Cannabis seeds. If you look at Siberia or the US Midwest where weed grows wild, they get freezing nights and warm days in the fall and spring in many cycles, and long term sub freezing temps in the winter with periodic thawing. Cannabis seeds are well adapted to surviving in that environment. While I do not recommend moving them around in temp, I recommend keeping them DRY in all cases and also freezing them ASAP. IMO refer temps above 40F are too warm for long term storage, but that is way better than 50F in a likely variable temp and humidity location such as in a back room of a house, a garage, or whatever.
5 Likes
There you go Mia, an answer from an expert in seed storage!
2 Likes
I’ve had great results in the refrigerator with 90%+ germination rates after 15 years.
6 Likes
@BigSur your advice probably extends the life of my little collection they are in the dry and fridge … but I add rice and I put into the freezer.
2 Likes
I have had this argument for years now. MANY books and mags, well, actually just about ALL magazines and books say not to freeze Cannabis seeds. They site no research though. Over on the 420 forum many people have absolutely blasted me for freezing them. But… if you look at the scientific research, mainly done in Japan, Cannabis seeds can be frozen for long term, and even possibly indefinitely. I get 60-100% germination from my seeds here, after being frozen anywhere from a year to 40 years now. I started freezing seeds in 1977, after the book, Marijuana Potency by Starks came out. Recommended reading, $5.50 used on Amazon. Or free by online download. My copy is falling apart after 40 years. I guess I better get another one? Or I should freeze the first copy?
13 Likes