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Welcome to the Southern California Horticultural Society,
where passionate gardeners meet to share ideas
and learn from each other

On the second Thursday of each month, we invite speakers to present a talk or program about their area of expertise. We are once again offering in-person meetings as well as live-streaming on Zoom (with registration).

Meetings may also include Plant Sales, a Raffle and expert discussion of plants brought in to the Plant Forum. Do you have an interesting plant to share? If you can't bring one in person, send in a photo and requested information on our Plant Forum Page.

For more information about the Society, please see our About SCHS page.

Next Meeting: 

Thursday, February 9th, 2023


SCHS Monthly Meeting:

Chris Cosma, PhD Candiate from UC Riverside


"Prioritizing California Native Plants

for Butterfly and Moth Conservation"

                                                                                           Photo provided by S. Steinmetz


For our February 9 meeting, the Southern California Horticultural Society welcomes Chris Cosma, a PhD candidate

in Dr. Nicole Rafferty’s lab in the Evolution, Ecology, and Organismal Biology Department at UC Riverside.  He will

be speaking to us about his research, which focuses on how climate change is affecting moths and their

interactions with native plants in California.


Cosma will talk about how the migratory Monarch butterfly was recently declared endangered by the

International Union for Conservation of Nature (IUCN), and that planting milkweed – the monarch’s obligate host

plant – is critical to protecting the species from extinction in the face of climate change and other threats. He will

also address the greater problem facing hundreds of other declining Western U.S. butterfly species, including

moths – which are ten times more diverse than butterflies – and how each species depends on specific native

plant species throughout its life cycle: host plants for caterpillars and nectar plants for adults.


Alongside his research, Cosma has developed a web application called The Butterfly Net that helps people find

the best native host and nectar plants for butterflies and moths based on locations within California. This tool

also shows “keystone” species of native plants that provide stability to entire insect communities. In his talk,

Cosma explains the science behind The Butterfly Net and how to use the tool to help protect butterflies, moths,

and the important services they provide.


If you’re still trying to decide what new plants to add to your garden, this program might aid you in making your

choices. Please join us in-person or online for this fascinating presentation. 


Held in-person at the Friendship Auditorium


Doors open at 7:00 p.m. / Announcements at 7:10 p.m. /

Plant Forum at 7:15 p.m. / Program begins 7:30 p.m. ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________  NOTE: This program will be in-person. For the safety of our guests (and in keeping with recent L.A. City Health Dept. guidelines) we strongly recommend that guests have updated vaccine status and that masks be worn indoors.

Visit our Past Meetings page to re-watch previously recorded in-person meetings and webinars, download each meeting write-up, and reference any materials provided by our speakers.

If you have been enjoying our monthly webinars and would like to help support the SCHS until we can meet again in-person, please consider donating any amount you feel you can. Even better, become a member, with levels beginning as low as $15. for the year. You can find details about the various levels of membership on our website at Join SCHS.

Thank you for your attention - we always appreciate your support!

Other Events and News

Thursday, February 9:

Chris Cosma, PhD candidate from UC Riverside, will speak on "Prioritizing California Native Plants for Butterfly and Moth Conservation" (Live and Online)

Thursday, March 9:
Renee Shepherd, founder of Renee's Garden seed company, will speak on "Garden to Table from Seed" (Live and Online)

  • Our Hort Happenings page lists events at local horticultural institutions. 
  • Follow us on Facebook and Instagram. Tag @socalhort in your photos to be featured on our page!
  • Want to re-watch a previous meeting, plant forum, or event? Visit our YouTube Channel for all available recordings!
  • Join our mailing list to be updated with important news about SCHS via email. Your email address will not be shared with anyone, and you may unsubscribe at any time.

Join us today and receive our monthly Newsletter, free admission to regular meetings and discounts on SCHS events. If you would like to support us without joining, please go to our Donate to SCHS page.

If this is your first time to log in as a current member, please enter the email you used when you joined SCHS, then click on the “Forgot Password” link below. In the next dialog, decipher the code and click Submit. A temporary password will be emailed to you, allowing you to log in. Feel free to change the password once you log in.

To renew your membership online, log in and go to your Profile. You will see an option to renew for another year. (Or follow the link when we send you a renewal notice.)

You can always reach us by mail at:

Southern California Horticultural Society
P.O. Box 94476
Pasadena, CA 91109-4476

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