Planting systems of sweet cherries in Belgium

Advising a planting distance or planting system is difficult. Factors such as soil type, cultivar, or rootstock have a big influence. Also the experience of the grower is an important factor. If one has little experience with the training and pruning of sweet cherries, it may be appropriate to plant wider. For intensive plantings it is necessary to prune consistently to avoid problems with growth. In 2003, we started a trial with 4 planting systems with 'Sweetheart' on 'Gisela 5'. Until now the classical system and the English system have done well. The Spanish bush, on the other hand, had very low productions in the first years. In the V-system the total production ha^-1 was obviously lower in yield than the other 3 systems, due to some disappointing production during the last years. In a second trial, 'Kordia' and 'Sweetheart' on 'Gisela 5' were planted and trained to a V-system in spring 2005. A V-system is labour intensive and so a very expensive system to establish. The V-system is best imposed on self-fertile cultivars. In this trial, 'Sweetheart' produced higher yields than 'Kordia'. 'Kordia' was very vigorous, even when the trees were repeatedly root pruned. A cultivar like 'Kordia' does not produce sufficient yields on the leader branches. This kept yield too low each year. In spring 2009 'Skeena' on 'Gisela 6' was planted as a classical system and trained to the UFO-system. Whips were planted at an angle under 45°. Shoots emerge from the central leader which are tied so that they grow upright in a narrow system. Up to now the UFO-system is very labour intensive, because of the time required for tying. In the first years, yield from trees trained in the classical system was 50% higher than for trees trained to the UFO-system. Fruit size, on the other hand, was almost the same for both systems. The next few years will reveal the utility of the UFO-system in sweet cherry production.