PLEASE NOTE: This site currently features extended information only for the Southern California region. Other regions will be expanded as information becomes available.
Invasive plants are by nature a regional or local problem. A plant that jumps out of the garden in one climate and habitat type may behave perfectly in another. This website is organized by region, so you can learn which plants are most problematic in your area, and what alternative plants make good replacements. There is also a California-wide guide to invasive trees.
Select your region using the map or the text links below: | ||
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How to use this website:
This site shows invasive plants commonly sold in nurseries, and gives suggested alternatives. These alternatives are acceptable for vegetation management zones because they can be pruned to decrease the accumulation of deadwood.
When buying plants, consider these alternatives, or ask your local nursery for other noninvasive, non-fire-hazard plants. If there are problem plants in your yard, especially if you live near a natural area, we recommend that you remove it and replace it with a suggested alternative. Invasive plants that spread by seed should be removed from all areas.
If you like an invasive plant's appearance, finding a replacement is often easy—some of the alternatives listed here are selected especially for their similar appearance. The recommended alternatives also thrive in the same environments and conditions as problem plants. We have suggested some California native plants, for those wishing to rediscover California's unique native plant heritage, as well as alternatives that are non-native but not invasive. When landscaping adjacent to natural lands or preserves, we recommend you use locally native California plants. We have tried to ensure that none of the recommended non-native plants are a problem. However, plants can adapt over time, and there is no guarantee some plants will not become pests in the future. If any plant is not watered or pruned, it may become a fire hazard over time. Many of these alternatives are readily available, though others may be easiest to find in specialty or native plant nurseries.
If you notice one of these alternatives invading natural areas, please notify Cal-IPC. Please note plant names carefully, since a few recommended plants may have invasive relatives—even in the same genus or family. Invasive plants such as pampas grass (Cortaderia), fountain grass (Pennisetum), and broom species have many cultivars and varieties. Until these cultivars and varieties can be independently tested and verified, they are not recommended as substitutes.
Project background
Many of the non-native plants that invade California's wildlands were originally introduced to the state as ornamentals. The horticultural industry, recognizing this threat to native habitats, joined conservation biologists at a workshop in 2001 entitled "Linking Ecology and Horticulture to Prevent Plant Invasions." This workshop resulted in the "Saint Louis Declaration on Invasive Plant Species," describing voluntary codes of conduct for professionals and the gardening public. In 2002, Cal-IPC began a program to educate the California horticultural community about the problem of invasive garden plants. Following meetings betwee weed scientists, land managers, and horticultural experts, the first "Don't Plant Pest!" brochure was published in 2004. To date, 60,000 have been distributed. Cal-IPC has recently joined Sustainable Conservation and industry representatives in a new collaboration aimed at preventing further plant invasions from horticulture.
What gardeners can do
Homeowners and landscaping professionals can help slow the spread of invasive plants by choosing non-invasive species for their gardens. The "Don't Plant A Pest!" brochures suggests alternatives for garden plants known to be invasive in California.
The brochures are the products of a collaborative effort that involved all the stakeholders affected by this complicated issue, including:
- weed experts
- UC Cooperative Extension (Master Gardeners)
- commercial and retail nurseries
- growers
- botanical gardens
- gardeners
- state and local agencies
- non-profit organizations
- land managers
How to Order
- Small quantities (up to 10) are available as free samples by e-mailing info@cal-ipc.org or calling (510) 843-3902. Please indicate whether you would like the San Francisco, Southern California, or Trees brochure.
- Packs of 100 are sold for $30 to cover printing and distribution costs. To order larger quantities with a check or credit card, print and return the Order form. To use this brochure as a model for your own materials, contact Doug Johnson at (510) 843-3902.
Nursery Wallet Cards (pdf)
If you are out shopping for your garden and see an invasive plant for sale, consider leaving one of these cards to let the retailer know about your concern. The file provided can be downloaded and printed on perforated cardstock or regular paper, then cut apart.
Other Information
Please see For Land Managers for information on removing invasive plants from your property. Much of this information is designed for larger plots of land, but some methods can be applied to smaller gardens as well.
Please see Invasive Plant Links for more organizations and government agencies that work on the issue of invasive plants.
"Keeping Aquatic Plants in Their Place: Common Sense Tips to Protect Lakes and Rivers" from Landscape Contractor Magazine (June 2005). Information for water gardeners, pond owners, and landscape contractors who install aquatic gardens.