Answer: Among the flowering trees, there are just a few with purple foliage from spring to fall and these are deciduous -- so they will lose their leaves each winter. You might look at some of the newer disease resistant crabapples (although these do have fruit) as well as the dwarf purple leafed plum or sand cherry (Prunus x cistena) which has very tiny fruit you probably would not even notice. There are also some larger growing purple leafed plums (named varieties of Prunus cerasifera) however they are somewhat subject to pest and disease problems. You might also consider some of the purple leafed forms of Cotinus coggygria or smoke bush. Your local professional nursery staff should be able to help you determine if you have a planting site suited to any of these and whether or not they would meet your criteria. Good luck with your new tree!
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