First: the caveat. With the possible exception of spiny Barberries (Berberis) there are no absolutely deer-proof plants. If the herd is large enough, and food is scarce enough, deer have been known to eat almost anything.
That said, there are some plants that are much less palatable to deer. If you have a problem in your neighborhood, it's probably a good idea to draw heavily from this list of perennials that are rarely browsed. If you can't live without certain plants that are candy to deer, you can plant them in an enclosed area, or use repellents in that bed, to try to minimize the damage.
Although it's the curse of gardeners that we crave what we can't grow (folks in Florida long for Lilacs, New Englanders for Agapanthus), it is possible to create a lovely garden using Deer Resistant Plants & Bulbs . It's a challenge, but not an impossibility.
Deer Resistant Plants & Bulbs tend to share certain characteristics: fuzzy or wooly leaves; pungent-scented foliage (Catmints, Mints, Lavenders, Agastache, Salvias, etc) and/or foul taste (even poisonous). Spines, thorns, and prickles protect some plants, such as Barberry, but we've heard from customers who've lost even Rugosa Roses to browsing—hard to believe for anyone who's ever tried to prune a Rugosa without drawing blood, but true.
If the deer herd is large, the youngsters can do some damage sampling plants and then spitting them out—we've heard of deer tearing up and then leaving Narcissus (Daffodils) and Digitalis (Foxgloves), both quite poisonous. That's how the young learn what's good—or not good—to eat.
Deer also tend to have regional tastes, so we've found the same plants on lists of both "rarely eaten" and "sometimes eaten." It's always a good idea to consult your local cooperative extension office and other gardeners in your neighborhood or town for advice. Deer also seem to have an uncanny ability to find (and eat) fertilized plants, so go easy on the nitrogen if you feed your plants.
Many serious gardeners resist the idea for a long time, but finally enclose at least some areas of the garden in tall deer fencing. It works. If the deer population is large, and the depredation severe, fencing becomes the best long-term solution, if you want to grow plants that deer love. Because deer are just as happy to wiggle under a fence as to leap over it, be sure the fence is secure at ground level. A six- to seven-foot tall fence is needed; gardeners in California developed the idea of using two shorter fences, about 4 feet apart, because deer are usually cautious about getting into any situation where they might be trapped.
We've compiled the following list of deer-resistant bulbs and perennials from research published by several cooperative extension offices in the northeast.
Deer resistant perennials for full to part sun
Asclepias tuberosa(Butterfly Weed)
Buddleia davidii(Butterfly Bush)
Chrysanthemum x superbum(sometimes nipped)
Echinacea purpurea(Purple Coneflower)
Eupatorium (Joe-Pye Weed)
Geranium (especially G. macrorrhizum)
Grasses, Ornamental (Calamagrostis, Miscanthus, Pennisetum, Festuca, Hakonechloa)
Gypsophila paniculata(Baby's Breath)
Monarda (Bee Balm)
Oenothera (Evening Primrose)
Perovskia (Russian Sage)
Platycodon grandiflorus (Balloon Flower)
Rosmarinus officinalis (Rosemary)
Stachys byzantinus (Lamb's Ears)
Verbascum sp (Mullein)
Deer resistant perennials for full or part shade
Convallaria (Lily of the Valley)
Dicentra (Bleeding Heart)
Digitalis sp (Foxglove)
Adiantum pedatum - Maidenhair Fern
Athyrium niponicum 'Pictum' - Japanese Painted Fern
Dennstaedtia punctilobula - Hay-scented Fern
Matteuccia struthiopteris - Ostrich Fern
Osmunda cinnamomea - Cinnamon Fern
Polystichum acrostichoides - Christmas Fern
Geranium (especially G. macrorrhizum)
Kirengeshoma palmata (Waxbells)
Primula sp (Primrose)
Pulmonaria sp (Lungwort)
Flower Bulbs rarely damaged by deer
Fritillaria imperialis (Crown Imperial)
Narcissus (Daffodil, Jonquil)