The idea of dry paper towel absorbing moisture is very helpful.

If you also include a small square of newsprint, it will indicate how dry the air is. It will resist stiffly or crackle if you bend it or crumple it when dry. When it is not bone-dry, it becomes limp.

You can also use dry rice as a desiccant, especially if it is very dry. You can assure that by baking it in a shallow pan until just before it turns brown. Then seal it tightly, quickly, in glass. (Hot rice may melt a plastic jar or bag.)

If daylily seeds are dessication-toleraqnt, or orefer very dry storage, you can use silica gel.

I use silica gel; in paper envelopes to keep tubs full of packets very dry. However, that's too big and ungainly for little 2"x3" Ziplocs. Maybe itg would be practical to add a tiny pinch of silica gel granules to big seeds like day lilly. The silica gel used for drying flowers is a little finer than table salt, with some dust.

But, if you use too much fresh silica gel in a tightly sealed tub or small jar, it can pull the relative humidity below optimum. Probably the best long-term cool storage moisture content is 5% to 7% (by weight) , and that is maintained by a Relative Humidity around 25% to 35%. But silica gel can pull the RH down to 10% or maybe lower if you let it!

That's no problem in a Ziploc, since humidity can diffuse right through thin plastic. It can probably move through the "zipper" even easier!

I bought some humidity-indicating cards with indicating spots for 10% - 20% - 30% - 40% - 50% & 60%.
I'd rather have had 5% steps from 5% to 20%, then 30% and 40%.

humidity cards - 40 cents each from Drierite: https://secure.drierite.com/ca...

ULINE seems to have a $70 minimum order for these! But only 18 cents each?
http://www.uline.com/Product/D...









==
http://www.southernexposure.co...
INSTRUCTIONS FOR DRYING SEED

Regenerate silica gel in the oven at 250F for 3-4 hours (not hotter).


http://www.seedcontainers.net/...
Long term seed preservation:
the risk of selecting inadequate containers is very high
César Gómez-Campo
Dept. Biología Vegetal, Escuela T. S. Ing. Agrónomos. Universidad Politécnica de Madrid. 28040 - Madrid. Spain.
E-mail: [email protected]


Buitink, J., Leprince, O., Hemminga, M. A. and Hoekstra, F.A. (2000). Molecular mobility in the cytoplasm: an approach to describe and predict lifespan of dry germplasm. Proceedings of the National Academy of Sciences. USA 97, 2385-2390.

Diaz, O., Gustafsson, M. and Astley, D. (1997). Effect of regeneration procedures on genetic diversity in Brassica napus and B. rapa as estimated by isozyme analysis. Genetic Resources and Crop Evolution 44, 523-532.
Ellis, R.H., Hong, T.D., Martin, M.C., Pérez-García, F. and Gómez-Campo, C. (1993). The long-term storage of seeds of seventeen crucifers at very low moisture contents. Plant Varieties and Seeds 6, 75-81.

Vertucci, C.W. and Roos, E.E. (1990). Theoretical basis of protocols for seed storage. Plant Physiology 94, 1019-23.

Walters, C. and Engels, J. (1998). Effect of storing seeds under extremely dry conditions. Seed Science Research 8, 3-8.

Thanks for that information, Ric. It sounds like a good routine to follow for long term storage of vegetable and flower seed.

I have never heard of anyone doing more than the little bit of paper towel with daylily seed. Many people only refrigerate it for 3-4 weeks for a brief cold period before planting. Others might keep them in the fridge over the winter. I believe it is desirable for the seed to stay plump.

I have kept them refrigerated all winter Up here where I live, with nowhere inside to start them early in the year, I keep mine dry, on a bookshelf, in open top envelopes, and direct sow outside in fall. That is an entirely different approach.

True, desiccants are only useful for long term storage, or perhaps short term storage in a humid rain forest!

I searched for, but could not find, information about how dessication-tolerant daylily seeds are. Not all seeds benefit from being dried down to 5-7% water content.

Usually I use paper (labels) as a buffer for humidity swings. I figure that they absorb some humidity when I unscrew the lid and open some Ziplocs, then release it gradually. When the relative humidity in the jar falls to 10%, each Ziploc would eventually get too dry. I figure that the paper labels inside each Ziploc slow that process down.