The vines are all he has left of his family that’s living. His family’s old accomplishments, his service record, his past deeds are all done, to be celebrated, but stagnant. The vines, and their wine, are still there to be nurtured; to have something NEW done with them. Picard couldn’t turn his back on his family legacy any more. He’s the last of the Picards, but the Picard name can still be spoken of in the present tense, thanks to the vineyard.
It could be that he’s being interviewed about his previous work and history, and that “in the present” he is indeed very much retired in his chateau.