At the heart of the matter is the fact that deer are eating machines. Although we can't match their appetites, most of us possess a superior intellect. Probably, the best way to deter deer is with a physical barrier. One option is always to fence the whole yard. For many, that would be impractical due to cost or unsightliness.
Many people achieve great results by fencing vulnerable groups of plants within a yard.
Feedback suggests that the best materials are tough poly or metal fencing. Trex deer fence is easy to work with, tough, and visibly tolerable. A good height is 7-8' and the fencing should be placed within a few feet of the plants it's protecting. Deer are unlikely to jump over a fence when they can't perceive a clear landing on the other side. If the fence is being used as a property perimeter, it should be higher.