This training technique -- also known as "free," "wild," "irregular" form, or "fan espalier" -- is the most common and probably also the oldest technique to train vines on walls. It is predominantly used outside wine-growing regions and is inferior to the strict cordon forms, because fans often become messy and unmanageable. Nevertheless, to provide a complete picture of vine training techniques, it is described here.
Fan espaliers can be further branched and varied (developed into an extensive and varied stem framework) depending on the situation-- in order to frame windows, for example. However, the number of arms and branchings has to be limited to ensure that there is a space of 0.5 to 1.0 metres between them at the outer edge of the vine.
For optimal results, the trained fan needs to be pruned with a combination of techniques, i.e., in the lower area preferably spur (short) pruning, changing to rod (medium-long) pruning in the middle, and to cane (long) pruning in the upper canopy. This can make it difficult for beginners. Unfortunately, due to a lack of pruning experience or knowledge, the espaliers quickly become messy and unmanageable if the stem framework and side shoot positions are not clearly separated.