Stop the spread of invasives: keep them out of your garden.

Southern California is a gardener's paradise. Not only do we live in an Eden-like setting, but also the mild climate allows us to grow a wide variety of ornamental plants from all around the world. Sadly, some of these exotic beauties are threatening what little is left of our naturally beautiful wildlands. In addition to the ecological cost there is an economic cost. One study estimates that the total cost of invasives to the U.S. is about $1 billion per year.

The California Invasive Plant Council tells us that 'Over half of the plants currently damaging California's wildlands were originally introduced for landscaping purposes.' For the most part, these foreign garden plants behave perfectly well in their intended roles. It is those few that escape the well-intentioned gardener's boundaries that become troublemakers in nature. These are the ones we need to be aware of and avoid. This becomes even more important the closer your garden is to a natural area.

The qualities that attract us to these plants, like pest resistance and ability to reproduce and flourish, are the very characteristics that make them successful invaders. In the wild they reproduce aggressively. Removed from their natural predators, they out-compete native plants for water and space. Unfortunately, invasive nonnatives do not provide food or proper shelter for the native animals and disrupt natural processes in other ways as well.

Cal-IPC's Web site, http://groups.ucanr.org/ceppc/Landscaping_Alternatives/, provides a brochure with pictures of common ornamental plants to avoid in Southern California gardens, along with some alternatives to consider when landscaping.

It is unfortunate there aren't warning labels on these plants at the nursery. Then you could avoid making the mistake in the first place. But if you do find any of the above invasive plants in your garden, the best thing to do is eradicate them and replace them with a noninvasive alternative. You may want to consider some native species. You could be an example to help get the point across to your neighbors, friends, and family.

Instead of shrinking what is left of our natural spaces by causing the spread of invasive plants, let's protect what we have and even expand nature by planting natives instead.