Answer: There are lists of deer resistant plants but to be quite honest, hungry deer will eat almost anything. An exception would be plastic flowers. Although they may pull the flowers out of the ground, it isn't likely they would actually consume them! When deer populations are large and there is competition for food, they will munch on even plants that have been reported as not attractive to deer. Here's a partial list: http://njaes.rutgers.edu/deerresistance/
You might advise your clients to use deer resistant plants in their landscapes but also suggest deer repellants (such as Deer Away) or barriers to protect their most precious plants. Aside from the above, 8' tall deer fencing is another way of controlling the critters.
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