California Horticultural Invasives Prevention: Cal-HIP

Friends of the Partnership Newsletter - Summer 2006

June 26, 2006

Topics of the Season:

Notes from the Project Manager
Cal-HIP meets at the Huntington Botanical Gardens
We need your feedback on three additional invasive species!
Cal-HIP Communications
Related News: Major Trade Organization Takes Action!
Recommend a friend!

Notes from the Project Manager

Hello, and welcome to the Summer 2006 edition of the Friends of the Partnership newsletter! Sustainable Conservation is pleased to share an update on our collaborative effort to address the unwanted spread of horticultural plants into open spaces and wildlands. Members of our steering committee represent the horticultural and environmental communities, and they continue to address invasive plants that are available for gardening and landscaping. Together, they are identifying non-invasive alternative plants and creating strategies for communicating their findings.

This newsletter shares the progress of the California Horticultural Invasives Prevention (Cal-HIP). We want to keep you informed, engaged, and aware of invasive plant issues in California.

Your comments and questions are always welcome, and we invite you to share your own projects and news with us. See below for a direct way to offer your feedback on three new species under consideration! Please feel free to be in touch - for contact information, see the bottom of this page.

Enjoy the summer, and keep in touch!

Terri Kempton
Project Manager, Cal-HIP


Cal-HIP meets at the Huntington Botanical Gardens

Jim Folsom led the Cal-HIP Steering Committee on a tour of the Huntington Botanical Gardens, sharing detailed information with the group about the plants and gardens in addition to behind-the-scenes information on the facilities and design. Highlights included the desert garden, the new outdoor children’s garden, and a twilight tour through the rose and herb gardens. The group recognized the Gardens as a major source of botanical information for the public that reaches new audiences. The Huntington Gardens provide a fun, engaging, positive way to capture interest and educate the public about responsible gardening, and they will play an important role in outreach and communication about invasives and their alternatives.

The following day was dedicated to Cal-HIP meetings to continue work on our message about the invasive plants we’ve identified and our strategy to educate the industry and the gardening public about our findings. More detail about our progress can be found below!

Jim Folsom leads tour

Cal-HIP member Jim Folsom, director of the Huntington Botanical Gardens, leads the group on a tour inside the succulent greenhouse.



We need your feedback on three additional invasive species!

Cal-HIP is addressing three high-profile wildland weed species for which some scientific questions remain: fountain grass (Pennisetum setaceum), pampas and jubata grass (Cortaderia jubata and selloana), and the ivies [Algerian ivy (Hedera canariensis), English ivy (H. helix), and Irish ivy (H. hibernica)].  Although some questions remain, Cal-HIP recognizes the importance of these plants in wildland invasions. They group is now developing a series of recommendations for these plants based on the best available information. 

Cal-HIP consulted with the academic community to review the latest science and began developing appropriate information for the horticultural industry and the gardening public. The following summarizes Cal-HIP’s proposal for the message about these three species.

Please send feedback on the following message to by July 4 th to be shared with the Cal-HIP steering committee!

Fountain grass  (Pennisetum setaceum)

· Green Pennisetum setaceum should be avoided in regions where it is an invasive problem.

· At this time, red Pennisetum setaceum varieties do not appear to be invasive.

Ivies: Algerian ivy (Hedera canariensis), English ivy (H. helix), and Irish ivy (H. hibernica)

· Some ivies are invasive; however, they are difficult to distinguish when growing in the wild.

· It could be that only a few species/cultivars are invasive while others are safe for planting.

· Cal-HIP is pursuing research on these ivies to understand which plants are safe for planting.

· In the meantime, gardeners should control ivy by keeping it well contained, trimming to prevent fruiting, and properly disposing of clippings and cuttings.

Jubata and pampas grass  (Cortaderia jubata and selloana)

· Cortaderia jubata should be avoided.

· If you live along the coast or inland near waterways, please use alternative plants in place of Cortaderia selloana.

· Research is ongoing to determine if sterile and low-fertility strains of Cortaderiaselloana are safe for use in the horticultural trade.



Cal-HIP Communications

Great progress was made on developing Cal-HIP’s outreach campaign to educate the industry and gardening public about invasive plants and their alternatives. The group approved a communications plan and created a complete list of materials and strategies to share the Cal-HIP message. They also discussed the tone and appearance of outreach efforts. These tools will come together to create a powerful educational campaign later this year.


Related News: Major Trade Organization Takes Action!

During their March board meeting, the California Association of Nurseries and Garden Centers (CANGC) unanimously approved voluntary codes of conduct that nursery professionals can follow to prevent aggressive garden plants from invading wildlands and open spaces. This landmark decision was a result of the leadership of Cal-HIP member Bob Falconer and a product of the group’s work to generate industry-wide interest in proactively addressing the issue of invasive garden and landscaping plants.

“By adopting the St. Louis Voluntary Codes of Conduct, the California Association of Nurseries and Garden Centers engages 1,200 member companies in the effort to stop the spread of invasive plants,” said Bob Falconer, the Executive Vice-President of CANGC. “Nurseries can play an important role by choosing not to grow invasive species and choosing instead to promote alternative plants that don’t cause problems in local ecosystems.”

CANGC is a highly visible organization that has set a trend for other industry groups around the country to follow. Their commitment to fight the spread of invasive plants shows that the horticulture industry can be an environmentally responsible “green” industry. CANGC joins the rest of the Cal-HIP members in developing a workable plan to replace invasives currently in the nursery trade with non-invasive alternatives.



Recommend a friend!

If you know of anyone that would like to learn more about Cal-HIP, please let us know! Help our network of Friends expand by referring colleagues or organizations that are concerned about horticultural prevention of invasive plants. They will receive an email with a link to the newsletter.


The Cal-HIP Steering Committee:
Developing and fostering implementation of strategies for preventing new and continuing introductions of invasive plants through the horticultural community in order to protect California’s naturalresources.


Carl Bell University of California Cooperative Extension, San Deigo
Bethallyn Black University of California Cooperative Extension, Contra Costa Master Gardeners Program
Sarah Connick Sustainable Conservation
Holly Crosson UC Davis Arboretum
Jennifer Chandler Landscape Architect, Northern California Chapter of the American Society of Landscape Architects
Bob Falconer California Association of Nurseries and Garden Centers
Jim Folsom Huntington Botanical Gardens
Andrea Fox California Farm Bureau Federation
Jim Gilbert Northwoods Nursery, Inc.; Mail Order Gardening Association
Kent Gordon England California Landscape Contractors Association
Angel Guerzon Landscape Designer, University of California at Santa Cruz Arboretum; California Native Plant Society, Santa Cruz County Chapter
Doug Johnson California Invasive Plant Council
Terri Kempton Sustainable Conservation
Chris Hopkins Home Depot
Betsy Peterson California State Floral Association
Mary Pfeiffer Shasta County Agricultural Commission
John Randall The Nature Conservancy
Craig Reggelbrugge American Nursery and Landscape Association
Sarah Reichard University of Washington
Nicholas Staddon Monrovia
Pat Thalken California Department of Food and Agriculture
Carolyn Villa-Scott Yamagami's Nursery

For more information, contact:
Terri Kempton
415-977-0380 x312

SusCon logo

Sustainable Conservation partners with business, environmental and government leaders to find practical ways that the private sector can protect clean air, clean water and habitat.