Gardening with Deer in Mind

By Botany Bob

Customers shopping in a nursery spot a plant that they like. They ask a litany of questions all to which the nurseryman can respond with a positive resounding yes and the sale is virtually made. Then comes the Kibosh, “Do the deer eat it?” End of the sale. It is sad and frustrating for nurserymen and customers. Frustration can be a driving force to learn.

Landscaping for deer resistance offers gardeners an opportunity to learn about fascinating new plants that come from some of the most remote and exotic places: the Australian Outback, the Greek Isles, the South African Veldt, for example. Take a trip to the UC Botanic Gardens of Santa Cruz. For the plant lover, it is as exciting as outer space is to the astronaut. There are also many good magazine articles, books, and pamphlets that rate plant material for deer resistance. When preparing to plant in an open area or front yard garden in any bayside or coastal area deer are of common concern and consideration in choosing what to plant and how to protect new plantings.

Imagine being a child, walking with a teacher in a class through an herb garden. With the special focus children give to learning, the teacher invites the children to smell, look closely, and touch the sage, rosemary, and various scents of thyme. Next, the teacher asks the children to inspect the arrangement of the leaves, noting they are always opposite and feature square stems, with flowers appearing to be structurally alike. Children in the class would also learn that these divine scents, all of the mint family as wonderful and as useful as they are, actually improve the plant’s chances for survival. Many animals that browse, like deer, find the chemical scents intolerable, if not poisonous. Althought alike in some ways, the body chemistries between mammals can be decidedly different.

In June, the Mint family (lamiaceae) literally bursts with every color of the rainbow, especially the New World Salvias, Old World Phlomis and Leonitis, as well as sage, rosemary, thyme, and lavender, all virtually deer proof. It is still advisable to spray anything newly planted with a deer repellent such as Liquid Fence once a week for three weeks to prevent deer from pulling recent plantings out of the ground. It may be that a plant newly moved from one environment to another emits a chemical signal that indicates soft growth or perhaps weakness that makes them particularly vulnerable and often targeted. Once a new plant is settled into its new home with proper light, amended soil, and moisture, it should be ready to take on the deer.

South African plants and Australian plants provide the gardener with an unlimited palette for deer-resistant plantings. Three prominent families immediately come to mind: the composites (daisies), myrtles and proteas. Among the first are Osteospermums, Arctotis, Delosperma (ice plants), Dimorphotheca, all from South Africa. Occasionally there are complaints about the deer nibbling these plants, but as habitat destruction continues, coupled with months without rain, even established plants are subject to some browsing if not protected. When these plants are grown in mass display or sprayed once a month with a deer repellent, there is little problem. All these varieties of daisies require full sun, ample moisture, some humus, and occasional fertilizer to succeed. Most problems occur when they are planted in the shade. One plant group of daisies, the Helichrysum, derived from the Greek roots helios, sun, and chryson, golden, never seem to fail. The plant group contains the straw flower which now comes in designer colors. Try massing golden Helichrysum heindrichii with lavender ‘Hidcote’ for a breathtaking display. This Helichrysum looks like the ubiquitous yarrow, but deer won’t touch it and it seems to always be in bloom.

Members of the Protea and Myrtle families from, you guessed it, South Africa and Australia are also highly deer resistant. They often reach their bloom climax in winter, when most plants are tuckered out. With the proper terrain of excellent drainage and sun, these plants thrive with the least care, which may be another garden tale.

Another defense strategy plants employ to avoid being eaten is to grow where nothing else can. As blue and purple spires of Pride of Madeira disappear all too soon in April, they are replaced in May by the common cottage garden Valerian, growing in the crevices of rocks and in nutrient poor soils on impassable cliff faces. Approaching from the north and heading toward the Golden Gate Bridge on Hwy 1, one cannot but be moved by this triumphant plant in every shade of red, pink, and brilliant white. In the City, this same plant, also known as Centranthus ruber, not to be confused with the herb Valerian, emerges from the crevices of sidewalks and where a smidgen of soil has gathered between the concrete foundations of buildings and the edge of driveways.