Gardening for the Senses

Gardeners develop and maintain ornamental gardens primarily for the visual appeal of beautiful blossoms and lush foliage. These gardens also please the sense of sight with the shapes of plants and the similarities or contrasts between plants.

Ornamental plants could also please three other of our senses:

  • Taste is served by certain plants that are both edible and ornamental, e.g., Saffron (Crocus sativus);
  • Touch is valued in plants that interesting texture, e.g., Lambs Ears (Stachys byzantina); and
  • Hearing relates to plants that rustle in the breeze, e.g., New Zealand Flax (Phormium.

There are more examples of ornamental plants that appeal to these senses, but they are minor features of the garden, relative to plants that appeal to our sense of sight.

The fifth important category of ornamental plants is the aromatic plants: those that appeal to the gardener’s sense of smell.

The blossoms or the leaves, or both, of aromatic plants, produce volatile compounds that are known as essential oils. Their primary purpose, of course is to attract pollinators, but people have found myriad culinary, medicinal, therapeutic, and even magical and uses of such plants. Books have been written about such desirable applications. Here, we focus on our enjoyment of the aesthetic appeal of aromatic plants.

Plants with aromatic foliage release their essential oils primarily during the heat of the day. When the sun goes down, the foliage must be rubbed to appreciate the fragrance.

In comparison, some aromatic flowers release their perfumes during the evening and night hours to attract moths that have evolved to reach the plant’s nectar through long corolla tubes,

Many aromatic plants produce pleasant fragrances during the daytime and can be desirable additions to the landscape. An online search for “aromatic plants” will yield the information needed to select and locate plants to optimize daytime and evening enjoyment.

For example, very popular evening-scented aromatic plants include Sweet Rocket (Hesperis matronalis), Border Phlox (Phlox paniculata), Honeysuckle (Lonicera), Evening Primrose (Oenothera biennis), Night-scented Phlox (Zalusianskya ovata), and Night-scented Stock (Matthiola bicornis).

The aromatic California native plants may be particularly interesting to gardeners in the Monterey Bay area. We appreciate the studies of Jackie Pascoe, a member of the California Native Plant Society, to select a few noteworthy plants in this large group.

  • Spice Bush (Calicanthus occidentalis) – wine barrel scent
  • Vanilla Grass (Hierogonum occidentalis) – vanilla scent
  • Fragrant Pitcher Sage (Lepechinia fragrans) – minty, but entirely unique scent
  • Coyote Mint (Monardella villosa) – minty scent
  • Wild Mock Orange (Philadelphus lewisii) – orangey scent
  • Cleveland Sage (Salvia clevelandii) – clean scent, “like a sweet desert morning”
  • Yerba Buena (Satureja douglasii) – wonderfully spicy scent
  • Catalina Perfume (Ribes viburnifoium) – fine wine scent

You could find some of these aromatic plants at the California Native Plant Society’s sale on Saturday. For info, see the story elsewhere in today’s newspaper.

Another good opportunity to learn about aromatic plants is to visit the Aroma Garden at UCSC’s Arboretum & Botanic Garden.

Explore the large and varied universe of aromatic plants to discover your preferences, and add a few to selected locations in your garden to expand your sensual enjoyment.

Right-size Plants for the Garden

While selecting plants to bring to your garden, considerations begin with basic cultural issues: exposure (sun, partial shade, full shade); moisture (infrequent; regular; ample); and drainage (fast, normal, boggy). Other more advanced cultural issues exist for future discussions.

Once we satisfy the basic cultural conditions, the selection process can proceed to aesthetic issues. There are many such issues, potentially, because they involve site-specific priorities and gardener-specific preferences. Today’s column addresses the mature sizes of plants as factors to consider when selecting a new plant for the landscape.

Plant size might seem an obvious concern, but an all-too-common error is to install a plant where it will grow eventually to intrude on a pathway, overwhelm nearby plants, unintentionally block a view, or reach over a fence into a neighbor’s space.

Such issues could arise with all kinds of plants, although some grow more slowly than others and could become a problem only after several years of maturation.

Thoughtful gardeners favor purchases of small plants, knowing that they could buy at lower cost by growing the plant themselves rather paying a nursery to care for the plant for one or more seasons. That’s a good and frugal practice for gardeners, and it brings the additional pleasure of watching the plant grow in the garden.

Garden centers often carry selections of herbaceous perennials and succulents in four-inch—and even two–inch—containers, and woody shrubs and trees in one-gallon or smaller containers. These small plants often have labels that indicate their mature size, and the gardener has the responsibility to read the label and select plants that are suitable for the space they are intended to fill.

Small plants can be misleading, however, when the label provides insufficient information about its eventual size, or when the buyer overlooks this important information. If the label doesn’t tell the story, search for the plant’s botanical name on the Internet to learn about its full size.

For example, I recently brought home a four-inch pot holding a Dasylirion longissima. The common name, Mexican Grass Tree, suggests its eventual size, which is eight-to-ten feet wide, with a flower stalk that could reach up to fifteen feet. I’m looking for the right spot to plant it.

Photo of Large Succulent Plant

Mexican Grass Tree (Dasylirion longissima) at the UC Botani cal Garden

My garden already has a Dasylirion wheeleri, a related plant that is known as Desert Spoon. This plant has already grown to its full size of three feet wide, and once developed an impressive flower spike over eight feet high. It is, however, too close to a walkway, and its leaves have saw-tooth edges that are inhospitable to passersby and the occasional weeder. I will need to bundle it before attempting to dig up and move it to a better spot.

Large plants can be excellent specimens in the garden so this “mature size alert” is not intended to discourage the use of botanical behemoths. Given enough space, big plants can be striking additions to the garden, but it’s best when the gardener knows their mature sizes before planting.

Inspiration for Next Year’s Garden

We are now one week into the fall season of the year (the autumnal equinox occurred last Friday. Now is the time to plant in preparation for the new season. In the spring, many gardeners become inspired as garden centers display flowers that have been nitrogen-dosed into bloom, but the fall is best for installing new herbaceous perennials, and woody shrubs and trees. This time is good for such tasks because the plants will have time to establish their roots during the winter months and prepare to burst into bud and bloom in the spring. As this underground growth happens, our seasonal rains (hopefully) will provide needed moisture.

Planting and transplanting involve the pursuit of landscape design visions, which makes the late spring/early fall also a fine season for touring gardens for new ideas.

The Garden Conservatory, a non-profit organization, conducts a national program of one-day garden tours, known as the Open Days program. The tours are organized in local clusters of three-to-five outstanding private gardens. The Conservatory publishes an annual catalog of Open Days events, which are scheduled from April through October.

Last weekend, I visited one of the Open Days clusters in San Jose, and volunteered as the greeter at one of the gardens. There were three gardens on tour: a garden designer’s “intensely private sanctuary” with extensive stone and cast embellishments; a design gem, once featured in Sunset magazine and recently recovered from five feet of flood waters; and an artist’s nicely designed and well-managed collection of palms, cycads, bromeliads, ferns and succulents.

I won’t attempt to describe these gardens in more detail. The direct experience is always best. These three gardens are not larger than standard city lots, and they each presented details that most gardeners could adapt for their own landscapes. They also have interesting and well-grown plants, one of which (shown below) I could not identify:

Photo of Unknown Plant in Container

Mystery Plant

This striking plant was in the designer’s garden, but he was not present when I visited. The flower resembles that of the Firecracker Plant (Cuphea ignea), but the leaves are quite different. I’m searching for its name.

Several design details caught my attention. I particularly liked the use of small black river stones (Mexican pebbles), which are available in several sizes. These can be used loosely as a stone mulch, placed in sand or concrete as decorative pavement, or in other ways as imagination might lead.

Another design detail of interest was the use of small Christmas light strings, woven into hanging metal pieces, e.g., chandelier, empty birdcage, etc. and serving a decorative lighting under a patio roof. Not everyone has a similar situation, but the effect would be attractive in the evening.

Thirdly, I was impressed by the use of very large carved stone, natural stone, and cast concrete pieces in a relatively small landscaped environment. Placing massive blocks requires bold commitment as well as physical effort, but such pieces express permanence with great clarity. Even a single specimen could be a strong addition to a garden, and a vote against more tentative actions.

Visit the Garden Conservatory’s Open Days website < www.gardenconservancy.org/open-days > for more information.

If you are ready to add plants to your garden, a good opportunity is the 5th Annual Native Plant Sale of the Watsonville Wetlands Watch. The sale will be 8:30–1:00 on Saturday, October 7th, at the organization’s resource center at the Pajaro Valley High School campus in Watsonville. The sale supports the group’s education and restoration programs in the Pajaro Valley. For info, visit www.watsonvillewetlandswatch.org/.