I just dug up a blueberry plant in my backyard and the root had a label attached saying "Mahoney's Rocky Ledge Farm and Nursery, Rt. 3, Winchester, Mass." and it looks like the date on it, written in heavy pen reads "4/19/41" Is that possible?

Unlikely '41! We began in 1959 :)

The company was started in the late 1950s. Maybe it's 1991.

It could be. I know they have been a family owned business for years.

Or maybe 1961, or 1971, or, 1981

Maybe it was a significant date to whoever planted it..or I agree possibly 1991

Bet they'd love to hear about it!