We visited two butterfly gardens on a recent trip to Santa Cruz. The two gardens take different approaches to providing butterflies with what they need. The different strategies contrast the nativist approach with an approach that emphasizes diversity. The more diverse approach seems to be more successful in attracting butterflies, at least in the case of these two gardens that are located within a few miles of one another, in very similar climate conditions.

Natural Bridges State Park is the home of a eucalyptus grove that provides shelter for overwintering monarchs from November to February. Only 550 monarchs roosted in the trees in November 2020. The population of migrating monarchs in California increased greatly in 2021 and the site at Natural Bridges was no exception. 2,100 monarchs were counted at Natural Bridges in November 2021.
Signs explain why eucalyptus trees provide the ideal shelter for overwintering monarch butterflies. They shelter the butterflies from wind and rain. Their canopies are open to the sunlight that provides the heat needed to keep the monarchs active and able to feed. Eucalyptus are blooming when the butterflies are roosting, providing the nectar the butterflies need to sustain them.

Remarkably, signs also inform visitors that other non-native plants, such as English ivy, provide monarchs with the food they need to live through the winter months:

Natural Bridges State Park also puts its money where its mouth is. Rangers have installed a butterfly garden in front of the ranger station that is an eclectic mix of native and non-native plants. Many are non-native favorites of butterflies, such as Buddleia (butterfly bush), cosmos, and Scabiosa (pin cushion flower). Both Buddleia and Scabiosa have been designated as “invasive” by the California Invasive Plant Council and are eradicated with herbicides by many public land managers. Natural Bridges State Park seems to be an exception to that unfortunate rule, possibly because they have observed what butterflies actually use and need.

Proving that point, here is an Western Tiger swallowtail butterfly nectaring on Scabiosa at Natural Bridges.

The Flip Side: UC Santa Cruz Arboretum and Botanic Garden
The second butterfly garden we visited was in the UC Santa Cruz Arboretum and Botanic Garden, just a few miles away from Natural Bridges State Park. The butterfly garden at the UCSC botanic garden is exclusively native and the narrative on its signs is consistent with the nativist agenda:


No monarch butterflies were observed in the UC Santa Cruz Arboretum and Botanic Garden during their 2021 California migration.
The UCSC botanic garden is well worth a visit. Its focus is the flora of Mediterranean climates: California, South Africa, Australia, and New Zealand. The garden is an opportunity to observe that many of our favorite plants come from other Mediterranean climates and observing them in July helps us to understand that planting a diverse, drought-tolerant garden can provide year-around blooms for pollinators and add color to our own gardens:


What does the tale of two butterfly gardens tell us?
I hope these pictures speak for themselves, but in case they don’t here’s the point of this post:
- Butterflies and other pollinators do not care where plants are from. They are looking for food and shelter. If non-native plants provide what they need, they will happily use them.
- Non-native plants from other Mediterranean climates are well-adapted to our climate. They are also drought-tolerant.
Do you know if Natural Bridges is getting any pressure/blowback for taking this stand? I am so surprised that they would do this. Somebody has a firm backbone there!
Why would they? You can’t argue with success. We spoke with the rangers. They were proud of their success with butterflies.
Many people have had great success raising monarchs in enclosures to protect from predators but it’s still prohibited.
There is strong evidence that milkweed planted near overwintering sites will NOT cause monarchs to reproduce out of season but the powers that be continue to advise not to plant any milkweed within 5 miles of the coast. I could on.
So I am surprised that a state beach would be allowed so much leeway to buck the system. Many people can and do argue with success.
Natural Bridges is not an enclosure. Butterflies are free to choose what they need. The changing climate changes when they breed. Read Monarch Mysteries Update here. Let them do what they need to survive.
There is no evidence that tropical milkweed is harmful to monarchs and much evidence that it isn’t. Hobbyists who have become the Nature Police have succeeded in getting a ban on the sale of tropical milkweed in Marin County. They aren’t helping monarchs who breed according to hours of daylight and warmer temperatures, especially at night. Try asking an academic scientist rather than a self appointed “expert.” Even Bay Nature understands this now.
Hi MillionTrees, (btw, is one of your email id’s ‘Eden’s Island’?) (I had that CD by Ahbez,… which I gave away, though kept the recordings on my computer)
Below is an email exchange I’ve had with Greg Rubin (plus another),…. and immediately below is my reply, though I’ve not yet sent this reply back to him.
Take a look at the exchanges, see what you think.
Thanks for your sharing your perspectives!
Scott Jones plantscomprehensive.com email: plantproco@att.net office: 619 223 5054 mobile: 619 302 1550
Not my email address. Don’t see the exchange you refer to. Sorry.
Let’s try again, I’m just copying and pasting:
Hi MillionTrees,
Below is an email exchange I’ve had with Greg Rubin (plus another),…. and immediately below is my reply, though I’ve not yet sent this reply back to him.
Take a look at the exchanges, see what you think.
Thanks for your sharing your perspectives!
Scott Jones plantscomprehensive.com http://plantscomprehensive.com/ email: plantproco@att.net plantproco@att.net office: 619 223 5054 mobile: 619 302 1550
Your copy/paste is not visible in your comment. Sorry.
Hi Million Trees,
I’m just trying to share with you personally, not on your email-blog postings.
Can we do that?
Thanks,
Scott Jones plantscomprehensive.com email: plantproco@att.net office: 619 223 5054 mobile: 619 302 1550
>
Mildredtrees@gmail.com
So glad to have a rational voice out there in the wilderness! At some point some common sense surely has to be applied.
I have lived in a Eucalyptus Forest called Scripps Ranch for nearly 50 years and have spent a great deal of that time battling the City of San Diego to keep them from cutting our forest down. We have been successful but it is a constant battle!
Just for some perspective, we may have as many as 1 million Eucs and certainly have ½ million.
I have monitored several of your terrific Bay Area organizations for over 20 years and have corresponded periodically.
Keep up the great work and let me know if there is anything I can do to help out.
Best Regards,
Will Lofft
BTW – Several years ago I was named the Scripps Ranch Lorax!
William A. Lofft
CFO
explorersLab
10635 Atrium Drive
San Diego, California 92131
+1 760.518.5917
lofft@mindspring.com
http://www.explorerslab.com http://www.explorerslab.com/
Thanks, Will. Good to hear from you.
Thank you so much for this wonderful, needed post!