Bud break is just as it sounds. The woody cane of the plant was one of last years growing shoots. After winter pruning, only one or two canes are left to be bent down and tied to the bottom trellis wire. The little buds on the cane swell in the spring (see the bud on the lower right) and finally burst forth with new growth.
What’s so important about that? These buds contain everything that will grow this year, leaves and fruit but also new buds at the base of each leaf stem that, on any canes we keep next winter during pruning, will burst forth next spring and provide the crop in 2015.
There’s so much in these little buds. Let’s just hope we don’t have any frost in the next few weeks. These new growing shoots are fragile and historically we can’t declare the possibility of frost until around Mother’s Day in May. There are secondary buds that plants have in reserve in case these first buds frost and die, but those secondaries are more about vine survival, so you won’t get much crop this year if anything. And you can imagine there would impact next year as well, because again, next year’s growth is in the buds on this year’s shoots.
Confusing, I know, but that’s why when it’s all said and done, we can have a glass of wine and ponder it all some more. Enjoy.