Posted 20 January 2017 - 10:37 AM
I save my pollen mixed with flour (plain flour, 1 part pollen, 40 parts flour) with some rice kernels inside tubes. Keeping it in the freezer will make it last up to 2 years.
Dry is the keyword, cool is an addition. Dessication should be started directly when harvesting pollen, even the air could render it useless.
However, a long time ago, a friend of mine kept a tube of pollen in his pocket, washed his trousers and the stuff still worked even after getting overgrown by fungus. That was a 1 in a million of course, but a single dash of pollen could in fact contain a million pollen kernels. In my own settings, I'd rather see 100.000 in a million.
There are reports of French hemp being pollinated by Moroccan pollen which travelled all the way to Europe by wind. It worked the other way around as well, and the Moroccan hasj yield was poor the few years after that.