How will you care for your bonsai over the winter? Generally, winter is a time to rest and just about every tree needs a period of slowed growth. Trees from a temperate climate have their rest period triggered by shorter daylight hours and lowered temperatures. Native trees can handle the cold but that is not the case for all bonsai trees, particularly tropical and subtropical trees
Wire cannot stay on forever, usually it can stay for about 6 months, but that depends on the time of year. For example in the winter, the tree isn't doing a lot of growing so it will take longer for the diameter of the branch that has been wired to expand enough to create a problem. In the spring and early fall ( September-October) many trees are in active growth, so you need to check the wire more frequently.