Hooved locusts: random notes on deer in the garden

Deer are a problem for gardeners throughout the Northwest, but on Bainbridge Island they seem a particularly voracious and indiscriminate bunch.  
Much of my work requires finding plants that deer will not eat, or will not eat much.  Beleaguered home owners may doubt it, but it is possible to plant a colorful, attractive landscape that does not look like free lunch to the Hooved Ones.

As a landscaper, at North Coast Natives I offer a Deer Munch Guarantee—if it turns out that the plant is eaten by deer any time between planting and fall (or if planted late in the season, then any time through the next fall) I will remove it and replace it with a better bet for deer resistance, or credit your account. 

The only fail-proof deer deterrent is a tall fence, but if fencing is not an option- what then?

Various measures (blood meal, commercial applications containing coyote urine, etc.) are said to repel deer.  They may be temporarily successful, but most are expensive, labor-intensive, and ultimately futile.

The remaining strategy depends upon plant selection.  Lists of “deer-resistant” plants abound on the internet, but I find that many of the plants included in these lists prove to be favorite delicacies for Bainbridge Island deer.  They’ll walk a mile for a Heuchera.  Astilbe leaves are left mostly alone, but the flowers are munched.  Though it's listed as deer-resistant, Aucuba (known to many gardeners by the name of a popular cultivar, Gold Dust) is eaten to the ground by deer. 
Much of this damage is seasonal: Aucuba is shorn closely by March, but rebounds during summer, when more appealing forage is available both in the woods and in people's yards.

Deer do not instinctively “know” which plants are toxic, or which don’t taste good.  It’s all empirical, and, one must assume, to some extent individual.  The size of the deer population, time of year, and what plants are available nearby are additional factors that may affect how picky your herds will be.

Nevertheless, there are some reliable rules regarding plant species, plant groups, and general characteristics associated with plants that are almost never eaten (the best you can hope for!)

Deer avoid plants with pungent, acrid or aromatic foliage. 

This includes nearly all members of the mint family- including true mint and many of the culinary herbs.  Deer will generally not even nibble Oregano, Thyme, Lavender, Russian Sage (Perovskia), all the true Sages (Salvia), Catnip, Agastache, Rosemary, Stachys (Hedge Nettle and Lamb's Ears) etc.  
Germander, a non-aromatic mint, is eaten by deer. (And while the munchingest deer on Bainbridge ignored a large stand of Monarda (Bee Balm) in the woods for years, I hear of deer elsewhere that grooved on the same species).

Deer reliably avoid nearly all members of the Daisy family, due to the acrid smell of leaves and flowers: daisies, asters, sunflowers, Ligularia, marigolds, Echinacea (Coneflower), dahlias, and many others. While slugs seem particularly fond of this family, I have never seen deer damage on anything in the Daisy family.

While deer do not instinctively know which plants are toxic, plants that are toxic enough to cause immediate unpleasantness will not be eaten a second time.  
Nearly all members of the buttercup family are at least somewhat toxic, some quite deadly. Hellebores do not get nibbled; the leaves are tough, and all parts of the plant are profoundly toxic.  Other buttercup relatives that are rarely if ever munched include Delphinium, monkshood, anemones, and Beesia . (Beesia's flowers may be nibbled slightly, but nothing more.)  Unfortunately, again-- while deer turn up their noses at the Buttercup gang, slugs seem quite fond of the leaves of these plants.
Also quite toxic and avoided consistently by deer are many or most members of the heather and barberry families (manzanita, salal, madrone, Rhododendron, Mahonia, Vancouveria, etc.)  

Deer will also usually (not always) avoid the Euphorbias, which are often (not always) mildly toxic.

Deer avoid foliage with unpleasant “mouth feel”, including very fuzzy or tough/leathery leaves.  These also happen to be characteristics often associated with drought tolerance in plants.

Deer will leave most hard-textured, evergreen grasses and most sedges alone. Most conifers are safe, as are maple and birch leaves, though trunk damage from antlers is not uncommon.  Deer like to browse on dogwoods, however, and will eat leaves and bark of Ceanothus.  

A plant’s being native or non-native has no particular correlation with its edibility.  Elderberry and Red-flowering currant are evidently quite palatable, as one would expect. All members of the Rose family are appealing to deer, including native roses, Serviceberry, Thimbleberry and Salmonberry.  (As a rule, if humans will eat it, deer will be delighted to eat it as well).

Deer are also happy to browse on members of the Mallow family, though those with coarse leaves (like Hollyhocks) might not be at the top of the list.  Deer LOVE most members of the lily familiy- true lilies, Hostas (if the slugs leave any behind), tulips. Exceptions are the very pungent Alliums, and the very toxic Veratrum and Zigadenus.  Deer are less fond of irises, but will eat some iris kin.  Crocosmia flowers seem to be yummy.

When researching the potential survival of a landscape plant on Bainbridge, I have grown less inclined to believe claims of “deer resistance” for many plants, particularly when those claims are made by people who wish to sell you the plant.  I look instead for anecdotal reports of what deer DO eat.  If any deer anywhere has eaten this plant, the Bainbridge Island deer will surely love it.