The annual lifecycle of the vineyard is dominated by pruning in winter, suckering in spring and of course harvest in the later summer. The Excelsior philosophy is that good wine is made in the vineyards and a lot of time and energy is devoted in particular to those three crucial landmark times. This time of year is dominated by ‘shoot thinning’ called suckering, a process that will take at least the whole month of October. Despite the sucky name it’s a essential part of looking after the vine – and the future wine’s – development.
Fertility increases the further up the shoot you go, peaking at the 6th bud but we took these off when we pruned the vine in the winter, typically leaving two compound buds per spur each of which develops into a primary bud sandwiched between two secondary buds. The compound buds that develop on the spurs are an evolutionary adaptation to weather and pestilence so that if the primary bud is damaged then one or both of the secondary buds will emerge to ensure the survival of the vine.
Vines are quite complex organisms and given the right conditions with ample water (and we have had a LOT of rain!) and fertile soil, it will probably produce many more shoots than desirable for the quality of wine produced at Excelsior. Our aim is not maximum production but to get a balance between growth and fruit. If we left very long spurs at pruning time we would get a huge amount of bunches and little growth. Even with good pruning it is still necessary to sucker to remove extra unwanted shoots ( ‘suckers’) from each of the vines.
At this point in the season it’s easy removal of these shoots, you can literally push them off by hand but if we left it much longer the shoots would lignify and we would be unable to remove them so easily, adding time and cost to the process. Pruning and suckering work hand in hand. The pruning in the winter is made easier by the suckering in the previous spring because there simply aren’t so many full grown canes to cut back, and suckering is made easier by winter pruning since the spurs have been cut to leave two compound buds (in theory) rather than letting everything get into a bushy tangle.
Every growing part of the vine is an energy sink – extra shoots or buds draw energy from the vine and from the fruit that we want to grow and mature. If you didn’t remove these extra shoots you run the risk of a very dense canopy and the buds inside may go into a vegetative, infertile state. Suckering also creates space to allow for better air movement within the cluster microclimate which is a natural remedy for fungal diseases, such as the dreaded powdery mildew.
If you don’t prune vines, and leave the grapes to ripen in full sunlight on the outside of the canopy, they will produce a very over ripe flavour like jam. Equally if grapes have too much shade they will produce unpleasant tannic flavours and red grapes wouldn’t have the proper colour so it’s important for the quality of wine to get the ‘dappled sunlight’ just right. Suckering efficiently means that dappled sunlight can penetrate the canopy, helping the all important flavour to develop during the ripening process.
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