Simple Vertical Cordon ("Columnar Vines")
This form is particularly suitable for narrow, vertical areas and/or for cultivating high quality table grapes. What may look rather rigid and somewhat unnatural at first glance, soon enough surpasses any "free" form espaliered vine: there is no tedious sorting of shoots, pruning becomes routine, and the trunk-stem structure remains very manageable.
History
This training method most likely hails back to France, from where it then migrated to the rest of Europe. It was described in Germany by Hardy / Jäger in their work "Obstbaumschnitt" ("Fruit Tree Pruning") as "Herzstamm" ("Heart Stem") in Erfurt in 1855.
Spatial Requirements
Not including the planting pit, each cordon needs a wall area of approx. 0.6 m x 1 m (max. 1.5 m x 2.5 m). For wider areas and the planting of several vines, space them about 1.5 m apart. To cover higher or larger surfaces, plant and train cordons at staggered heights (see diagrams below).
Trellising / Support
To support a vertical line of vines, install at least one wire rope; three would be ideal, spaced 30 to 40 cm apart, to allow young shoots to twine or be tied to wires on both sides. For very narrow areas, use 2 wire ropes and guide the shoots to one side only (see photo). Classic wooden trellises are also very suitable with this method.
Training and Annual Pruning
The diagrams at the bottom of this page will assist you. The yearly vertical growth is about 50 to 80 cm; i.e, about 4 new branches. Once it has reached a certain maturity, there will be max. 8 - 12 branches or a max. distance of about 2 m between the lowest and highest canes; otherwise, the lower shoots will fail. The vertical cordon will end approximately 50 cm below the top of the trellis. After the framework has been formed, spur pruning (short pruning) follows, ideally with the green shoots tied to or tucked behind the single wire or two outer wires. The vigorous growth of the uppermost part of the vine requires rod pruning (medium pruning). At a later stage and over the course of 2 - 3 years, switch to cane pruning (long pruning) the several branches (see diagrams below), starting at the top of the cordon, moving to the lower ones, leaving only about 4 - 6 branches per cordon and increased distance between the individual tiers... to be followed by yearly summer pruning if needed.
Photo illustrating Diagram 11 (see further below). The trained cordon and its extension are firmly tied to the timber stake with either a hard binder or soft rubber tape (Elasto-Band).
Form 01: Alternate Pruning: for each shoot from which the fruiting shoots will grow, the type of pruning switches every year from spur (short) to cane (long) pruning and back again ~ "alternating pruning." This gives the canes, which may have been weakened by cane pruning and high yields, a chance to recover during the following year, and to develop sufficiently vigorous shoots/canes for the cane (long) pruning that will follow.
Form 02: "Arched Canes": the remaining canes have been cane (long) pruned and - because the wires were horizontal - very slightly bent and tied to the wire ropes (so, horizontally). It is not necessary to leave replacement spurs on the branches; on a horizontal rod all eyes grow with the same vigor; even close to the branch, the shoots will be strong enough for the following pruning.
Form 03: "Semi-Circular Canes" / Half-Arches : Here the canes of all branches have been bent and, because the supports are vertical, tied into half arches. This way the new shoots will be at staggered heights, allowing the grapes to be better distributed so they do not press into each other (in contrast to simple arched canes; see previous photo). The distance between the branches on each side should be 60-80 cm.
Cordons at staggered heights in a palmette formation (several parallel arms), spur (short) pruned. For a cane-pruned version, the 1.5 m wide spacing must be increased to about 2 m. If needed, the arms of each double palmette can be arranged so that only two axes, instead of four, are created (see diagram here in yellow) and the vines can even be planted together in one planting pit ~ "quiver planting."
