What does “bud break” mean for a grapevine?

Bud break is the point in the grapevine's annual growth cycle when the first buds on the vine begin to open and new shoots emerge. This typically occurs in the early spring, when temperatures begin to warm up and the days start to get longer. For many grape growers, bud break is a critical milestone because it signals the start of the growing season and the beginning of the grapevine's annual cycle.