I'd like to try it but I've only heard the very basic idea. It is aparently to cause the plant to focus on growing roots and not leaves or flowers.
Though I'd like to try it I'd be nervous about killing the tree, especially as they cost so much.
When leaves are dried and fall off he plant the trees.
Ich lege die Bäume auf die Erde, decke die Ballen zu und warte, bis die Blätter vertrocknet sind. Der Baum ist ein Lebewesen, er hat nur ein bestreben: Er will überleben. Ich setze ihn ein, ich gieße ihn nicht, ich dünge ihn nicht. Er findet sich selbst zurecht. Wenn ich ihn beim Pflanzen gieße, wasche ich die Nährstoffe aus. Der Boden öffnet sich, weil er denkt, es kommt Regen. Aber rundum ist es trocken, auch die Luft, und so geht der Stickstoff verloren. Ohne mein Eingreifen bleibt der Baum selbstständig. - Sepp Holzer about planting trees
My translation: "I lay the trees on the ground, cover the roots and wait till the leaves are dried up. The tree is a living being who has only one goal: He wants to survive. I plant him in, I don't water him, I don't manure/fertilize him. He cares for himself. When I water him after planting all the nutrients are washed out. The soil opens up because she thinks it is starting to rain but all around the tree it's dry. Even the air is dry. Therfore nitrogen is lost (by watering trees after planting). Without my interference the tree stays self-depending."
Having lived in a damp country like england and a dry one like Spain were the potatoes start to lose their turgididty in a week or two, so it is better not to buy too many at a time unless you like cooking floppy potatoes but the bread never goes moldy, unless you keep it in plastic and can be used for crumbs a year, even years later while bread in england goes moldy and never dries out i could neveras a child understand about feeding people in dungeons on dry bread and water but in Spain i myself just eat up the dry bread if i have run out of fresh. Where the compost dries out rapidly and all kitchen waste resembles bits of dry leather in a day or two while in England compost usually suffers from beign too wet, I would say that instructions about how long you have to keep something like a live tree damp for, should vary a lot according to the climate.
ALso i am not sure it would be possible to keep a bought tree alive without watering it through its first summer in spain. maybe if your swale system were good enough. agri rose macaskie.