The winter was particularly mild, free of frost but very wet, and there were many more rainy days than the average during the first quarter of the year. The heavy rainfall continued during the spring, with higher than average temperatures.
Under these conditions the vines started budding relatively early, on 4 April for the Merlot and Cabernet Sauvignon and 7 April for the Cabernet Franc. Mild, rather wet weather prevailed through May and June, and as much rain fell during the first six months of 1988 as in an average year.
Mid-flowering was observed between 26 and 29 May depending on the variety. The vines flowered evenly over a short period, enabling the fruit to set more or less normally, and there was little coulure or millerandage despite the climatic conditions. A hot, dry summer caused veraison to occur slightly earlier than the average, though it was less even than the flowering.
Mid-veraison was noted on 12 August for the Merlot, 15 August for the Cabernet Sauvignon and 16 August for the Cabernet Franc. Too much rainfall in spring and too little in summer disrupted the vegetation cycle and the vines suffered from an unbalanced water supply. However, showers in early September followed by very hot weather allowed the crop to mature normally. In weather conditions that favoured the spread of disease, effective treatment ensured that the vines and grapes were properly protected and the harvest produced a healthy and abundant crop.