I think before I did that I would do something like Triss does with her baby jars instead. But that's just me. Mucking about with rice just seems like it would be a pain lol. I'm in a very humid area down here in Virginia and I've never had a problem with the humidity and the seeds. Although I do get very lumpy salt & sugar lol. So I would say it probably isn't a problem for your seeds and not to worry about it. But if it makes you feel better it can't harm anything that I can think of.

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