The temperamental chardonnay grape is small, thin skinned and fragile. It is expensive to grow, harvest and age because it is easily affected by changes in the weather and in the soil, which affects the flavor and aroma this grape imparts on wine.
About midsummer, the grapes begin to turn translucent, signaling that harvest time is near. The grapes then begin to sweeten and swell with water, diluting the acid concentration. Growers then monitor the grapes daily, measuring sugar levels and tasting for ripeness.
About 100 to 120 days after flowering, the grapes should be ready to harvest. In warm areas, the harvest usually starts in mid-August, but in cool areas, the harvest starts in late September.