Judean date palm seed has a 2,000+ year viability
I saw a recent article on the revival of the once extinct Judean date palm (an ancient Phoenix dactylifera cultivar) discussing how, in the 1960’s, a clay jar containing 2,000 year old seeds of the Judean Date palm was unearthed in an archeological dig at the site of Herod the Great‘s palace in Israel. Four decades later in 2005 botanical researcher Elaine Solowey decided to attempt to germinate a seed. He was successful. The palm seedling has since flowered and is considered to be the oldest known tree seed to germinate.
Here’s a link to the full article: Extinct tree grows anew from ancient jar of seeds unearthed by archaeologists
And some basic background information on the Judean Date Palm here.