Gardening with Exotics

Many of the plants we enjoy in our gardens produce flowers. We also enjoy many plants for their foliage, but the flowering plants, called angiosperms, are the ones that attract our attention.

The angiosperms, which first developed about 245 million years ago, have grown to dominate the terrestrial ecosystems, exceeded only by the coniferous forests.

There are about 260,000 species of angiosperms, and the growers of the most popular garden species have produced countless selections, hybrids and cultivars. When we visit our local garden centers or flip through catalogs of mail order plants, we see most often those variations of the most familiar plants.

Some avid gardeners eagerly seek the latest introductions of roses, irises, petunias and other and take pleasure in being among the first in their communities to have the hybridizers’ newest achievements. Each year, when we might think that new versions of popular plants are not possible, we find unexpected colors, new color combinations, more vigorous or more floriferous producers, and plants that have been bred to be more resistant to pests and diseases.

These new introductions are often the most costly plants offered, reflecting both their appeal to consumers and the costs of development and introduction. The most enthusiastic collectors of the best and latest do not flinch and gladly pay the premium prices.

Gardeners who appreciate unfamiliar and interesting plants have alternatives to each year’s new crop of high-priced new introductions. The vast array of angiosperms includes many exotic, garden-worthy plants with gorgeous blossoms that are rarely seen in garden centers or catalogs, and are very much worth the time and attention of gardeners.

The local gardener’s search for exotic flowers will be most successful when focused on plants that are well suited for the special growing conditions of the Monterey Bay area. These include plants from the world’s “summer-dry” climate regions, including coastal California, the central coast of Chile, the southwestern coast of Australia, South Africa and of course the Mediterranean basin.

A wide selection of interesting plants is native to these areas, and will succeed in the Monterey Bay area with routine care.

One example of an interesting exotic from a summer-dry climate is the Giant White Squill (Urginea maritima), which is a member of the Asparagus family (Asparagaceae). This plant, which is from the Mediterranean basin, has an enormous bulb (perhaps the largest of any plant), and an unusual annual cycle. It grows in the winter: large leaves appear from November to about May, when they yellow and dry, and the plant goes dormant. Then, in late July, it sends up a dramatic flower spike, up to five feet high. Each spike has a raceme of hundreds of tiny white or pinkish-red flowers.

Click to enlarge. Giant White SquillClick to Enlarge Giant White Squill - CU Unusual plants that will grow w ell in your climate, can add a good measure of interest to your garden. Watch for exotic selections in your garden center or garden catalogs.


The Giant White Squill has interesting characteristics.

  • All parts of the plant are toxic.
  • The flower stalks will continue to blossom after being cut, so you could bring a stalk indoors to watch the progressive opening of the blossoms.

For information about “uncommon and astonishing” plants, visit the website of Louis the Plant Geek. His website has information on many exotic plants, and includes photos of the Giant White Squill in leaf.

Gardeners oriented to reading could look for the book, Bizarre Botanicals, by Larry Mellichamp and Paula Gross (Timber Press, 2010). It could be in your local public library or book store, and is currently available on

Wherever you find exotic plants for your garden, always favor plants that are suitable for your garden’s growing conditions. For most gardeners in the Monterey Bay area, remember that such plants are native to the Mediterranean climate region.

Be horticulturally adventuresome while increasing your chances for success!

The Future of Hybridizing

The future of hybridizing has already begun; we soon will see the transformation of Nature’s ancient methods, and the rapid introduction of amazing new cultivars.

The basic method for creating new varieties of ornamental and edible plants has been practiced by bees and other pollinators for a very, very long time. This approach, called crossbreeding, involves sexual propagation: fertilizing one plant with the pollen of another plant produces seeds that carry the traits of the two plants. When the seeds germinate, the next generation of plants shows combinations of the traits of their two parents.

Plant hybridization has advanced greatly since 1900, when modern genetics began on the basis of Gregor Mendel’s work, but still follows the natural process. Rather than combining plants randomly, like bees, human hybridizers try to combine the traits of two plants to produce hybrid plants that are better than either parent. With ornamental plants, for example, a hybrid’s blossoms might be larger, more attractively colored, more numerous, etc.

This process requires time for seeds to germinate, develop into new plants and reproduce to produce a marketable number of hybrids. Often the majority—or all— of the seedlings do not equal the hybridizer’s vision, and are discarded, so that the process begins again.

Genetic researchers recently have developed ways to hybridize plants faster and with greater control than has been possible with the bees’ method. The new approach uses “genetic marking,” a technique to identify the gene or gene combination that results in a desirable trait in the plant.

The modern hybridizer then crossbreeds plants with desirable traits, grows the resulting seeds, and analyzes the genes in the hybrid to determine if it exhibits the desired trait(s).

A second, related development is the seed chipper, a device that determines if seeds will produce plants with desired traits. This process of “breeding without breeding” greatly speeds conventional hybridization.

Monsanto Company is pioneering the new methods for accelerating and controlling hybridization. These new methods do not involve transferring the genes from one species into another species so they differ from Monsanto’s highly controversial work in genetic engineering.

The new methods have been applied to vegetables: tomatoes, lettuce, peppers, broccoli and onions. Some “super produce” has already appeared in selected markets.

Given the progress of technology, we will see “super ornamentals” in the near future. Today, we can only speculate about how they will look and how they will grow.

New methods, new plants, and new questions!


Basic “how-to” descriptions of the traditional methods for hybridizing plants are readily available. Search the Internet for “hybridizing plants” or a similar phrase. The methods are really the same for all kinds of plants, but find information for specific plants by searching for “hybridizing roses,” inserting the plant name of interest.

For example, the article, “Try Your Hand at Hybridizing Irises,” appeared in Fine Gardening magazine, and was published originally in William Shear’s book The Gardener’s Iris Book (Taunton Press, 2002).

For more information on the new technology for hybridizing, see Ben Paynter’s article, “Monsanto Is Going Organic in a Quest for the Perfect Veggie,” in Wired Magazine, or “Monsanto’s Technology Platform in Wheat,” on the website of Monsanto Company. More detailed information on this technology is available on the Internet. Search Wikipedia or the Internet generally for “marker-assisted selection” or “molecular breeding.”