Here's my quick take:

So, in Washington('s home), they found some previously-undiscovered, but perfectly-preserved "food" that they're keeping "chilled" from pre-Revolutionary war days.

"...the bottles have been concealed in darkness" Containers -- boxes? -- have been hidden and the contents concealed from the public for a very long time?

Sounds like someone dug up some old documents in Washington DC that they've got on ice until the time is right to make them public.

Pre-revolutionary war days = prior to Trump becoming president?

"Scientists discovered 54 cherry pits and 23 stems. Bradburn hopes the seeds will be viable for germination — that a new window into the past may now be opened."

Seeds of data/information/hints are hopefully viable for "germination" = there is hope that this data will grow into something much bigger and open a new window on some past event.