Gisela 6 is a new semi-vigorous rootstock for sweet and acid cherries.
Gisela 6 produces a slightly larger tree than Gisela 5, roughly equivalent to the apple MM106 rootstock, and similar or slightly smaller than the popular Colt cherry rootstock.
The main advantage over Gisela 5 is that it is much less fussy about soil conditions, and in most situations it produces a free-standing tree which does not need support - however in very light soils and / or exposed windy situations you might need to consider staking.
A typical commercial planting density would be 700 - 1200 trees per hectare. For the garden or small orchard allow 3m-4m between trees.
Gisela 6 is a precocious rootstock, and trees are likely to start fruiting within 2-3 years.
In terms of climate suitability it is cold-hardy and suitable for use throughout Europe. However commercially Gisela 6 is mainly used in hot climate cherry-producing regions such as the USA west coast and Chile.
Overall Gisela 6 is arguably a better choice for the home orchard than Gisela 5, as the extra vigour means less expertise in tree management is required in order to get good crops.