How much wall space does a grapevine need? Is it better to grow one plant or several? This section assists you with the planning of your wall greening project and finding an appropriate training method. The tips can - with some reservations - also be applied to climbing roses, espalier fruit, and other climbing plants.
First you need to consider which (sunny!) part of the wall is suitable to be greened with grapevines. An entire gable, a strip of wall or an angle can be used as a greening area. Greening areas should have a distance of 30cm from windows and doors, not just for architectural reasons, but also to prevent creepy-crawlies from entering via the grapevines. And because grapevines need watering, a greening area should be no lower than approx. 50cm off the ground.
The minimum area for a grapevine is 1m x 1m or 0.5m x 1.5m (width x height). Although a single vine can cover 50sqm, training to reach this size will take many years. That is why large greening areas are divided up into smaller sections with several plants allocated, so that each grapevine has an area of 3 to 6sqm of wall space. It is best to plant several varieties to minimise the risk of failure. Plant spacings vary depending on the training form and circumstances. Eg you may want to plant only one grapevine because creating several planting areas in the street pavement is too expensive. It is also possible to plant 2 to 3 vine varieties in the same planting area ("quiver" style planting).
Selecting the correct Training Form depends on the size and shape of the greening areas. For beginners, Garlands and, with some reservations, Fan Forms are particularly suitable. All other training forms, though manageable, require particularly rigorous pruning. It is also important that beginners concentrate on one training form only, even if several areas are to be greened.
Trellises don't finish flush with the perimeters of the greening area, but rather are set back on all sides by 10 - 20cm. The shoots and leaves will grow past them, and are trimmed back in summer to stay within the planned dimensions of the greening area. Depending on the desired width, trellises can have 1 - 3 or more parallel wires. Under Trellis systems you find further tips for each appropriate training form.