Gardening with California’s Monocots

The pink flowers of Allium unifolium highlight a native garden featuring a variety of California monocots, including irises, grasses, and sedges. Photograph by Saxon Holt

The pink flowers of Allium unifolium highlight a native garden featuring a variety of California monocots, including irises, grasses, and sedges. Photograph by Saxon Holt

The enormous variety of bulbs and bulb-like plants is one of the most remarkable features of the native California flora. They are the focus of a new book, the introduction to which is excerpted here. It is followed by the first of four plant portraits from the book, each to be accompanied by one of Kristin Jakob’s exquisite drawings.

Imagine, for a moment, a city or suburb in which residential front yards, commercial landscapes, parking lots, streetscapes, and public parks feature plants compatible with their natural surroundings, evocative of the local history, and synchronized with the seasons. Many of these plants may not be native to the geographic spot in which they grow, but all fit comfortably into a regionally appropriate landscape scheme. They look right, feel right, and connect us instinctively to the natural order of things. “A thing is right,” wrote Aldo Leopold in A Sand County Almanac in 1949, “when it tends to preserve the integrity, stability, and beauty of the biotic community.” We could add that a thing also seems right when it stirs collective memories of a place, building on the past and anticipating a congenial future. Native plants, skillfully integrated into a private garden or public space, have the matchless ability to do all of these things.

Why do we choose alien plants when there are so many native plants, better adapted to the climate and soils of the area and more likely to thrive without extra attention? The most commonly mentioned reason for the preference for nonnatives is that people tend to choose plants that remind them of home, and many Californians have migrated here from other parts of the world. Those other lands support many beautiful landscape plants, some of which require considerable effort and resources to keep them alive in California, while others have adapted so well to our climate and soils that they spill over into neighboring
wildlands and crowd out native species.

Two other reasons for the prevalence of nonnative plants in California gardens have been the general lack of knowledge about California natives and the perception that natives, difficult to grow, are the province of experts. Native plants also have been slow to appear in the nursery trade, so in the past many good landscape plants have not been widely available.

Over the past two hundred years, as more than a thousand nonnative plants were introduced into the California flora, about the same number of the state’s native plants became rare or endangered and almost thirty became extinct. Conversion of wildlands to agriculture and urban development have played a major role in the disappearance of the state’s native plants, but anyone who clears a piece of land and creates a landscape entirely of nonnative plants contributes to the decline of native species.

There are several steps Californians (and others throughout the West) can take to preserve our native plants. The most important may be to preserve entire habitats by setting aside wildlands where typical, rare, or endangered species occur in significant numbers. Botanic collections of representative species also help to ensure that these plants will not become extinct. And each of us can make a small but important contribution by including at least some native plants in our gardens, by encouraging nurseries to make attractive and suitable natives available in the trade, and by sharing our knowledge and appreciation of native plants with colleagues, friends, and neighbors.

Wild Lilies, Irises, and Grasses: Gardening with California Monocots was written to encourage gardeners, homeowners, landscape designers, and others to consider natives when designing, planting, and evaluating plans for landscapes in California. The team of authors, who wrote from personal experience in growing and propagating native plants, focus here on native monocots, a large and varied group of flowering plants that includes lilies, irises, grasses and grass-like plants, orchids, agaves, and even palms.

What Is a Monocot?

With more than 230,000 described species grouped into about 400 plant families, the world’s flowering plants, or angiosperms, are the dominant group of plants on land and the major component of the vegetation in most natural ecosystems. Flowering plants occupy a greater range of natural environments than any other land plants, from tundra to tropics and from deserts to aquatic ecosystems. They exhibit an enormous range of life forms, from short-lived annuals to long-lived trees and shrubs.

Two major subdivisions of angiosperms have long been recognized: the dicotyledons, or dicots (having two cotyledons or embryo “seed leaves”), which constitute about three-quarters of all flowering plants; and the monocotyledons, or monocots (having a single cotyledon).

Although no single character can invariably distinguish monocots from dicots, a few general distinctions are useful for horticultural and field identification purposes. In monocots, the numbers of petals, stamens, and other flower parts generally are divisible by three; the typically narrow leaf blades usually have a number of primary veins that run parallel the length of the leaf (the small connecting cross veins are inconspicuous); and the diffuse, fibrous roots arise adventitiously from nodes in the stem rather than from a primary (“tap”) root as in most dicots.

Most monocots are herbs, and none forms true wood (stems do not thicken year by year through production of growth rings). Tree-like monocots, such as palms, bamboos, and some yuccas, are supported by the thick-walled cells of a strong but non-woody stem. Most monocots grow from bulbs, corms, or rhizomes; a few are vines. There are about 60,000 species of monocots in some sixty families, although any estimate of the number of families is speculative, because classification of flowering plants, especially of the larger families, is in a state of flux.

Excerpted and adapted, with permission, from Wild Lilies, Irises, and Grasses: Gardening With California’s Mono-cots, a beautiful and inspiring new book edited by Nora Harlow and Kristin Jakob, and published in 2004 by University of California Press and the California Native Plant Society. An exhibit of drawings and watercolors from the book, all by Kristin Jakob, can be seen at the Helen Crocker Russell Library at Strybing Arboretum through June (see Calendar, page 52).