Winegrowers Supplies  -  Development Stages of the Vine

In 1977, Dr K W Eichhorn and Dr H Lorenz, classified grapevine development in 47 stages, which occur between the first stage 'winter dormancy' and the last stage 'end of leaf fall'. The dates when these stages occur are dependent on the environment in which the vineyard is planted. Knowing the stage of your grapes during the growing season has many useful applications.

If problems arise during the growing season, a grape specialist helping solve your problem will need to know what stage of development your grapes were at when the problem manifested. Communicating this information helps pin-point what problems would most often exist during this stage of grape development.

Culture and chemical applications are often prescribed at certain stages of grape development. For example, bunch thinning/removal is sometimes performed when the berries are pea-size or smaller. Often you will see chemical labels refer to certain stages when chemicals should or should not be applied such as pre-flowering, flowering, and bunch closure. For the chemicals to be effective in controlling pests, chemicals should be applied at stages as specified on the label.

The stages published originally by Dr K W Eichhorn and Dr H Lorenz, in 1977, were:-

01          Winter dormancy
02          Bud swelling
03          Wooly bud: the brown wool is clearly visible
05          Bud burst: the first green (or pink) of the shoot is visible

07          First leaf unfolds and extends from the shoot
09          Two to three leaves unfold
12          Five to six leaves unfold: the inflorescences are clearly visible
15          Inflorescences get larger: individual flower-clusters are tightly packed

17          Inflorescences are fully developed: the individual clusters are extended
19          Flowering begins: the first flower caps free themselves

21          Full flowering: 25% of the flower caps have been shed
23          Full flowering: 50% of the flower caps have been shed

25          Post-flowering: 80% of the flower caps have been shed
27          Fruit set: fruit buds get larger, cleaning up of the berries is concluded

29          Berries are the size of grain, bunches begin to go downwards
31          Berries are the size of peas, bunches hang down

33          Beginning of the conclusion of bunch formation
35          Ripening begins: berries become translucent, begin to lose their colour

38          Berries are ripe for harvesting
41          Post-harvest: wood-ripening is concluded

43          Start of leaf fall
47          Finish of leaf fall

There is now a Modified Eichhorn-Lorenz system:-