Dormancy is the temporary diminution or cessation of a plant’s growth, usually slightly prior ot and during winter in the temperate zone. Occasionally the term, dormancy is also applied to the land itself. Thus the state of the land during periods in which no primary crop is being grown is said to be a state of dormancy. Note, however, that a secondary, or "cover" crop may be grown on the land during periods of dormancy.
Now that you know what dormancy is, let's consider why it's important in landscaping:
The best time to transplant many plants and the best time to prune some of them is when the plant is in a state of dormancy, because, while the plant is dormant, you do not run the risk of stressing it or interfering with its growth processes. For more on pruning and transplanting, consult the following resources:

