millerandage

right|thumb|A grape cluster with signs of millerandage with small, immature berries scattered throughout the bunch. Millerandage (or shot berries, hens and chicks and pumpkins and peas) is a potential viticultural hazard in which grape bunches contain berries that differ greatly in size and, most importantly, maturity. Its most common cause is cold, rainy or otherwise bad weather during the flowering stage of the vines though other factors, such as boron deficiency or fanleaf degeneration, may also play a role.

While millerandage always causes a drop in yield, its impact on wine quality varies, particularly by grape variety. For some varieties that are prone to uneven ripeness within a cluster, such as Sangiovese, Zinfandel and Gewürztraminer, the development of millerandage may be unfavorable due to "green flavors" from the potentially unripe grapes hidden within the cluster. For other varieties, such as Pinot noir or the Mendoza clone of Chardonnay, wine quality could be improved due to the reduced overall berry size and higher skin to juice ratio.