In recent years I've had quite a bit of experience sowing old, indeed very old, seeds. Most had been stored in air-tight containers (e.g., glass jars) in refrigerators. It was surprising to see what germinated, although not all seedlings survived for more than a few months (perhaps because of the age of the cellular components). There were even some startling results, such as a single Celmisia from a packet more than 10 years old (it's still alive 2 1/2 years later, and this is the first time I've ever germinated a single one, even from fresh seeds I collected myself). People, including myself, who received seeds from the dispersal of a very large seed bank accumulated over more than 20 years by Betty Lowry of the Seattle area, have reported somewhat anecdotally on their results for an article that is planned for eventual publication in the NARGS Rock Garden Quarterly. I have also received long-stored seed from Gene Mirro and Ron Ratko. In general, species from particularly arid regions tend to have seeds with long viability, as could be predicted. Among monocots, Calochortus and the Themidaceae seem to do this. In proper storage conditions, Lilium seeds can have very long viability (and I'd guess this also applies to Tulipa). The literature on seed germination tends to make doctrinaire statements about viability, and my personal experience makes me doubt some of those. That experience also misled me into thinking, for instance, that Fritillaria seed can't be expected to germinate after long storage -- yet I got very good germination of F. conica (a desirable species) from the Lowry hoard. You will read that certain genera must be fresh to germinate, but observation tells us that within a genus there can be both short- and extended-viability species; examples are Anemone and Erythronium. Some authors write that all the Ranunculaceae are short-viability, but there are definitely exceptions; for instance, I've raised several Delphinium species from stored seed. The conclusion I'd offer is that you should sow any seeds you have, perhaps retaining a portion of those that are especially rare and desirable for later use -- or sharing with other good growers. Indeed, sharing seeds with others who may have different growing conditions or skills is the best way to ensure that good plants remain in cultivation. Thus, I'm glad I sent part of my share of the Lowry seeds to Bob Nold in Denver, Colorado, who was able to work successfully with some steppe species I couldn't manage here in the Pacific Northwest. Jane McGary Portland, Oregon, USA On 11/27/2016 11:21 AM, Sylvia Sykora wrote: > In reviewing my seed collection for winter sowing I find myself with packets of seed, many dated more than two or three years ago. Does anyone know of a list by genera, at least, of viability times for stored seed? I know this is not a subject with hard and fast rules, but even some general guide lines would be useful and save time and energy sowing seed that's just too old to germinate. > > Thank you. > > Sylvia Sykora > SF Bay Area >