How much wall space does a grapevine need? Are several vines better than one? Here we'll assist you with the planning of your wall greening project and finding an appropriate training method. The tips are (more or less) also applicable with climbing roses, espalier fruit, and other climbing plants.
First you need to consider which (sunny!) part of the wall is suitable for greening with grapevines. An entire facade, a gable, a strip of wall, or even an angle can be used as a greening area. Greening areas should have a distance of 30 cm from windows and doors-- not just for architectural reasons, but also to prevent creepy-crawlies from entering your home via the grapevines. A greening area should be no lower than about 50 cm off the ground to allow room for watering.
The area designated for a house grapevine should be at least 1m x 1m or 0.5m x 1.5m (width x height). Although a single vine can cover 50m², growing to this size takes several years. This is why large greening areas are usually divided up into smaller sections of several plants, so that each vine gets an area of 3 - 6 m² of wall space. It is best to plant several varieties to minimise the risk of failure (this way, the vines spread over time and you can avoid losing the whole thing at once in the event of extreme weather events). The space between vines will vary depending on the training form and circumstances. For example, one may try to manage with only one vine if it is too expensive to dig into pavement. It is also possible to plant 2 - 3 different vines in the same planting area/pit ("quiver" style planting).
Selecting the correct training form depends on the size and shape of the greening areas. For beginners, garlands and fan forms (with some reservations) 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.
Climbing aids should not end flush with the outer edges of the greening area, but rather are set back on all sides by 10 - 20 cm. The shoots and leaves will grow past the trellis system, and are meant to be 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... you will find further instructions under wire rope systems for each respective training form.