Photo by Brian Jahn.
How long is male pollen viable for if stored in a cool, dry place out of the sunlight? — Processor of Truth
As long as your male pollen is kept cool, dry and completely airtight, it should last for at least a couple of months. However, pollen is always most viable in the first week or so of harvesting it.
If you truly need to store it long term, be sure to use a desiccant to absorb any excess moisture before placing your light-tight and sealed container in a cool dark closet or cupboard. Avoid the freezer or fridge due to high humidity levels.
Keep in mind that the effectiveness of male pollen will decrease over time, and your best bet is to always use fresh pollen in your breeding experiments. I’ve heard of breeders keeping pollen stored for over a year with little degradation, but like I said, it’s always best to use it sooner rather than later.