Pruning weight per vine / Cane no. at pruning
Mid-winter is an important time for pruning vines in the UK. If you record the weight of material pruned off each vine and the cane number at pruning time, then you can work out the weight of each cane and understand the vigour of each vine.
Assessing the vigour allows you to determine how many buds per vine you want to prune to. For example if you have high vigour (or heavy canes) then prune for lots of buds to try and manage leaf growth to be less. Some vineyards choose to record no. buds per vine as a clear record (and good check) of what actions were taken in the vineyard.
The pruning weight is also used as a guide to whether the vineyard needs more nitrogen applied. Soil analysis of nitrogen can be very variable depending on the time of year and recent rainfall, so using pruning weights to give an indication of low (or high) vigour, enables the manager to work out which plots need more nitrogen (or compost / manure on organic vineyards).
It is very important in vines not to over-apply nitrogen because then the vines will grow lush dense green canopies at the expense of fruit quality – they look very healthy but the grapes are all shaded and acids don’t ripen properly.
[Photo credit: Bride Valley Vineyards – follow them on instagram here]