In the Detroit Free Press gardening section last week there was a review of a wonderful product, PlantSkydd. It comes in both liquid and granular and works wonders on repelling deer. The products work to certain heights and the granular appears to last for 6 weeks.
The beauty of this product is that you can fill knee hi type nylons with about a cup of this stuff and hang it about and repel deer from many heights and areas. It also repels other pesky animals like chipmunks and what-not. And it is safe for vegetables and edibles.
Hope this helps.