The following is a fairly typical year in a vineyard in the Northern Hemisphere such as France. Readers should note that vineyards in the Southern Hemisphere such as Chile, Australia, South Africa etc. harvest during February/March which is their autumn. It is also useful to remember that vintage dated wines from these regions are always six months older than their European and U.S. counterparts.
January The vineyard is dormant and often frozen. Leaves have fallen from the vines. Winter pruning begins with the removal of unwanted canes to stimulate new growth and stem vigour. In France, by tradition, winter pruning started on St.Vincent's Day, 22nd January and is still adhered to in some regions.
February Pruning continues and must be completed well before budbreak to allow for the 'wounds' on the vine to heal. Cuttings are taken for indoor grafting onto rootstocks. These will be cultivated for planting out as new vines in the spring of the following year. Vineyard machinery is checked and serviced.
March The vine awakes and sap starts to rise. Pruning has finished and fertilisers are spread. Grafting continues and the vineyard is cleared of dead shoots and canes. The soil is lightly ploughed to aerate the base of the vines. Supporting stakes are checked and replaced as necessary. Some budbreak in warmer regions.
April Earth is removed from the base of the vines (Debuttage). One-year-old nursery cuttings are planted out. New shoots emerge from the vine. Canes are tied down on wires. Frost is a serious worry as it can damage the vines at this delicate stage. A severe frost as happened in 1991 can obliterate the crop. In frost prone regions e.g. Chablis and Champagne, heaters are used at night in the vineyards. Expensive, but often essential.
May Vigorous growth of new shoots. Frost still a danger. New plantings continue. Spraying against oidium* and mildew commences. Shoots are tied town on wires (Accolage) - left to itself the vine would create too much shade. Suckers are removed to encourage sap to the productive shoots.
June The vine starts to flower (floraison) - weather conditions vital. If temperatures are correct (18-20C) flowering will complete within about 10 days. Trimming of shoots, tying down and spraying against insects continues. Vintage will generally take place 100 days after flowering.
July Summer pruning to remove excess foliage and expose the flower sets. Some thinning of sets to ensure compliance with yield requirements. Spraying continues, weeds are tended to, vigorous growth continues and berries have formed.
August Berries start to swell and change colour. Weeding continues but spraying ceases. Vines are kept trimmed and fruit exposed for maximum ripening. Birds must be kept away - netting is sometimes used. Machinery and winery equipment is cleaned and made ready. Warm sunny weather desirable.
September Sugar levels in the grapes increase, colour deepens and acidity levels drop. As grapes continue to swell and ripen, sugar levels are checked on a regular basis using an instrument known as a refractometer. Harvesting of early ripening varieties commences. Vital decisions are taken whether to wait an extra week for more sunshine and more sugar or risk rain and some dilution.
October Harvesting continues in earnest with later ripening varieties. Manual and mechanical harvesting are practised in different regions. Hand picking is still considered the best. Although slow and labour intensive, it minimises damage and allows for greater selectivity of individual grape bunches. Harvesting by machine is expensive but has great speed and flexibility and can be used at night when temperatures are lower. The vintage is usually complete by the second week and the vineyard is tidied, ploughed and spread with fertiliser - often pressed grape skins.
November Soil is redistributed to cover the base of the vines to protect against frost (Buttage). Manure and fertilisers are spread. Pruning and removal of this year's shoots. These are gathered and burned. The sap falls back and the vine returns to its dormant stage.
December Generally a rest month in the vineyard and an opportunity to taste the new vintage. Soil that has been washed away by rain is returned to keep the vine base covered. Winter pruning commences in some regions.