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Chapter 11 When To Repot Your Bonsai




                    Bonsai cannot be repotted at any time of the year; for the majority of species,
               there is a small period of time during the Spring where the roots can be disturbed
               and pruned with reduced risk of danger to the tree's health. Though there are tree
               species that can be repotted at other times of the year, the purpose of this article
               is to describe and highlight the best time for repotting the typical deciduous

               bonsai in Spring. It is well known (and is frequently referred to in the Species
               Guides at Bonsai4me.com) that bonsai should be repotted 'when the buds start to
               extend', but, what exactly does this mean and exactly when does this happen? It
               is not possible to specify exact calendar dates for repotting. Different tree
               species require repotting at slightly different times and different trees of the
               same species can be ready to repot at slightly different times, even those grown
               in exactly same climate. Different climates can dramatically effect the exact date
               of repotting; repotting time in Florida will take place weeks before repotting in
               New York. However, nearly all tree species follow the same series of stages of
               bud growth in Spring and these can be used to identify the best time to repot
               your bonsai. This process should be well understood if you are planning on
               gifting someone these small potted trees.




                    Why Repot in Spring?

                    As temperatures slowly rise in early Spring, the roots of a bonsai slowly
               become active. The energy resources of the tree that have been stored in the
               roots over winter begin to move back up into the tree. As they do, the dormant
               buds on the branches (produced in late Summer and Autumn of the previous
               year) begin to swell.
                    This is the signal that the tree is beginning to come out of dormancy. As

               ambient temperatures continue to rise through the next weeks, move of the tree's
               stored energy moves from the roots, up into the tree in readiness for the
               explosion of new growth as the tree comes into leaf. At this point, the roots stop
               being an energy store and their primary function is to supply the newly opening
               leaves with moisture from the ground. This process can be followed from start to
               finish by observing the state of the buds visible on the branches on the bonsai.
               This process can be broken down into 4 stages;
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