Most hobby vintners are delighted to just see the foliage on their vine, but it is when the grapes emerge that they get really excited! If, in addition, the grapes taste sweet, one quickly concludes that a very talented gardener must be at work indeed, even though the grapes' sweetness can almost be taken for granted.. In this section, we will disclose some hints how you can produce particularly large and juicy fruit, so-called "table grapes!"
In contrast to vineyard grapes for pressing, which should have only small berries with high sugar content and aroma concentration, table grapes can be watered generously (Image 03). Watering is particularly effective when the grapes are about the size of peas: it promotes cell division in the fruit, and these numerous cells will swell up with a lot of water. However, too much water towards the end of summer can cause single berries to split in some varieties.
By thinning bunches to max. 1 - 2 bunches per cane, the remaining grapes will grow larger and sweeter (Image 04). Those bunches which are furthest away from the woody stem ie at the end of the cane are cut off, and it is essential to finish this thinning process before veraison, ie before the berries start to turn blue or transparent green-yellow.
Shortening the fruit canes back to 5 - 8 leaves beyond the last bunch can, in some varieties, increase berry size, as long as this is done well and truly before veraison (Images 05/06). According to old grape growing tradition, only 1 - 2 leaves should be retained on each cane beyond the last grape (Images 07/08). However, it is best to leave such radical trimming to experienced vintners or gardeners and only if observations made of the vine over several years have confirmed that there is no risk of frost damage. Occasionally, fruit cane trimming can encourage a strong growth of axillary shoots in July / August, which will increase canopy management work.
Ultimately, the motto "the proof is in the pudding" is valid for every vine, and after a few years it will become evident as to which maintenance work during summer is necessary or useful for producing better fruit.