4 pages and I'm surprised at the lack of mention of using flour and rice for storage. No worries, here it is.
Pollen viability can last for 10 years in a freezer, though viability is definitely decreased at that point. The trick is to use cooked flour as a buffer for the pollen.
- Collect your pollen and dry it completely. If you live in an area with more than 30% RH, you'll probably want to seal it in a container with some dessicant. The important part is to dry it as completely as possible.
- Measure out about 50 - 100 times as much flour as you have pollen. Put the flour in a skillet and cook it over medium heat. Keep stirring the flour until it slightly browns. Take the pan off the heat and let it cool completely.
- Do the same with a handful of rice and let it cool completely
- As soon as the flour is cooled, thoroughly mix the pollen and flour together.
- Make foil packages/bindles which will hold half to one gram of pollen. LABEL THEM CAREFULLY! A ball-point pen works well, leaving an imprint which can be read when the ink wears off.
- Put pollen in a bindle, add a few grains of rice and double fold the opening so the bindle is closed.
- Toss the packet(s) in a thermos, seal it up and toss that in your freezer.
The thermos protects the packets from micro-changes in temperature, as the freezer door is opened and closed. A chest freezer, which isn't opened often, is ideal.
To use, take the packet from the freezer and let it defrost at room temperature for a few hours. Open it carefully and dust your flowers lightly. Enjoy!