Budbreak (or budburst), is best described by using the BBCH-scale. This scale, is one of several that defines the phenological development (growth) of winegrapes, has assigned 2 digit codes and descriptions for every growth stage. These begin at 00 (dormancy) to 11 (first leaf unfolded) to 61 (beginning of flowering) to 89 (berries ripe for harvest) and ending at 99 (all leaves have fallen off the vine in late fall).

Budbreak occurs over a number of days – the length of this growth stage is determined by the variety, location and weather. Here are some of our own pictures to explain the stages of budbreak:

Growth Stage – Sprouting – Code 05 – brown “wool” clearly visible
Growth Stage – Sprouting – Code 07 – beginning of budbreak – green shoot tips just visible
Growth Stage – Sprouting – Code 09 – budbreak – green shoot tips clearly visible
Growth Stage – Sprouting – Code 09 – budbreak – green shoot tips slightly opened
Growth Stage – Leaf Development – some leaves unfolded

We will be adding the budbreak information from this year as it happens! Here is the information we have so far:

2009-2011 Budbreak by Variety
Chardonnay Viognier Malbec Cabernet
2009 March 15-21 March 22-28 March 29-April 4 April 5-11
2010 March 7-13 March 21-27 March 28-April 3 April 4-14
2011 March 19-28 March 26-April 2 April 4-11 April 7-16

2011 Order of Budbreak by Varietal:

Petite sirah
Petit verdot
Sauvignon musque
Sauvignon blanc

This Spring has been an interesting mix of really warm and really cold weather that has definitely affected budbreak. It warmed as Chardonnay was in the middle of budbreak hastening that process while also encouraging the Petite sirah, Petit verdot and Viognier. Then it got quite cold and has stalled the rest of the varieties as the buds struggle to open. Another interesting year!