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Spur pruning vs cane pruning? As I understand grape structure a cane is long growth that came from last years buds. A spur is similar but it accumulates bud growth that has been managed for several years, and eventually looks ugly.
In pruning my goal is to get down to a productive number of buds which are on one year old wood. In doing this if I have a spur with multiple years of growth projecting off a cordon (arm), I may look at it and say it is getting ugly! So for the production two years down the road, I will trim off the whole spur back to the cordon. This encourages a dormant bud in that area to become active and take over the role of providing a new bud on one year old wood which can produce fruit this crop year. When pruning a five or ten year old plant I have plenty of buds so I am constantly asking 1) where are buds that fruit this year and 2) what will look good two years out. I take most of the one year wood off so I can see what is on the cordon / arms to work with. , , , , Next I look for spurs which are getting old, they may have growth that represents four years. I size up how many fruiting buds will remain and start trimming older spurs to encourage growth of one year old wood closer to the cordon / arm.
On a new two year old plant I am training canes to establish a two cordon structure that fits my trellis. If I had an arbor or shade structure I might train four young canes into cordons. ? ie where do I want the plant to grow? I don’t ever keep long canes after the basic form is filling the trellis. Grapes are weeds. By year four pruning is managing the excess of growth.
