Simply stated, the Goblet Trellis system aims to create a more vertical growth pattern for the grapevine canes, with a single level of fruit that hangs side by side on adjacent wires below the leaf canopy. The canopy forms a “Y” or goblet shape from support arms of tubular, epoxy-coated steel, that extend outward from the posts and are fastened to them by a cross brace.
The system uses many more wires than a conventional trellis and for this reason may be objectionable to growers who are seeking a less expensive way to do things. Altogether, nine wires are needed. Three wires are attached to each side of the two-sided trellis, at heights of 28, 48, and 68 inches. In the center of the trellis at about 24 inches in height, right above the “V” of the base of the upright arms, is a training wire for tying up trunks. Extension arms of the trunk are trained out to the lower wire on each side. In quadrilateral fashion, fruiting canes of eight to ten buds each are tied in each direction along the wires on each side. Renewal spurs are located here too, so each vine will have a total of four canes and two to four spurs. Above the training wire, on the right and left, are two more wires that are used for summer training of foliage. As the vine shoots grow upright from the lower wire, the catch wires are gradually raised and shoots tucked in between this wire and the three outer wires. The purpose, which is the reason the system works, is to keep the center of the goblet free of leaves; to create, in effect, two curtains of leaves. The curtains are summer pruned as needed.
The goblet trellis performs particularly well for cool climate growers.