Answer: Pruning is generally best done in winter so that you can see the branch structure, however a very light shaping could be done almost any time. Keep in mind that pruning should be kept to a minimum so as to preserve the natural shape and character of the plant, as well as to reduce the number of cuts. (Each cut provides an opportunity for insect or disease to enter the plant.) To be honest, the fringe tree (which is often naturally a multistemmed shrubby form rather than a single stemmed tree form) grows rather slowly and the redbud sounds a bit large for a homeowner to tackle; you might wish to consider some professional help from a professionally trained and certified arborist rahter than doing it yourself.
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