About Louise Hallberg
Known as “The Butterfly Lady,” Louise Hallberg—with her signature sunhat shading sky-blue eyes—has welcomed local school children and adults from around the country into her gardens. Through guided tours and photographic presentations, she promotes and inspires an appreciation of butterflies and their conservation. A meticulous record-keeper, her years of daily sightings have earned her the respect of America’s leading lepidopterists. She has been featured in national magazines and videos, and she and her gardens have received many local and national awards.
Louise grew up in a home where her family had been stewards of the land since 1883. She attended local schools, traveling to Analy High School in an electric streetcar. She graduated from UC Berkeley and worked 35 years as Registrar for Santa Rosa Junior College.

At age 99, Louise continues to take an active role in her work. The Hallberg Butterfly Gardens were incorporated as a non-profit foundation in 1997 and placed in trust for future generations to enjoy. To learn more about Louise and her work, visit hallbergbutterflygardens.org.

Tell us about your background.

I was born in Sebastopol but have always lived here in this house above Graton. My grandfather and grandmother, John F. Hallberg and Louisa Neta Pearson, came from Sweden in 1883. They cleared the land of scrub timber and brush and planted apples, along with prunes, pears, hops, berries and cherries. My grandfather built the two-story house on the hill nearby—a Victorian. My grandparents planted the original apple trees and the sons kept it going—my father and uncle. When they couldn’t do it, my sister and brother-in-law, Esther and Haven Best, took over the farming. My uncle, then cousin, had the orchards along Highway 116 and the apple cannery in downtown Graton, the Hallberg Canning Corporation Cannery.

When did you first become interested in butterflies and why did you make it your life’s work?
When I was going to Oak Grove Elementary School, we were studying flowers and birds, but I never heard about butterflies. My mother was one of the first members of the Graton Community Club [founded in 1914]. She planted the Dutchman’s pipevine in the 1920s in her garden and eventually the butterflies found it. It was food for the black caterpillars that became the Pipevine Swallowtail butterflies.

When I retired from SRJC, I began seeing the caterpillars on the Dutchman’s pipevine, and many butterflies flying. In April 1990 I called Strybing Arboretum [now the San Francisco Botanical Garden] because they were having a sale on butterfly plants. I mentioned we had maybe 50 Pipevine Swallowtail butterflies flying in my yard. The volunteer who answered the phone—Barbara Deutsch—kept talking. Soon Barbara, Don Mahoney, Strybing curator, and Jeff Caldwell, a San Francisco landscape architect, came to see the butterflies. Jeff immediately said ‘you have to plant north of your house—it is too shady and cold around the house for your butterflies.’

From that time on, we have been planting for butterflies. We started with the strawberry tree, then got some butterfly bushes (buddleia) and rose-colored Centranthus and Verbena—and every year since then we have been adding both nectar and host plants. Nectar plants feed the butterflies and host plants are essential to provide food for the larva of butterflies: caterpillars. Each butterfly species requires a specific host plant.

How many species of butterflies have you documented?
We have had more than 50 species of butterflies—some we have seen only once or twice. We started keeping written records of butterfly sightings in 1992. A kind volunteer types it up at the end of every year, showing how many of each species we saw each day during each month.

What are the most prolific butterflies on your property?
Pipevine Swallowtails are the most numerous. We see many different kinds of Skippers. We also have the Anise and Tiger swallowtails, Buckeyes, West Coast Ladies, and the Cabbage Whites. The Mourning Cloak is an overwintering butterfly; it is usually the first one we see every year.

How important is it to you that the butterfly gardens serve an educational purpose?
I opened the gardens first to Oak Grove School in 1988. We became a nonprofit in 1997, and since then, we’ve had 33,000 people come through the Gardens, many of them children. I was doing tours, butterfly presentations and slide shows throughout the county for many years. We had more tours in April this year than we have ever had.

Two years ago we had 500 people come to Open Gardens, practically everybody was from Sonoma County. Open Gardens is our fundraising event held once a year, the last Sunday in June. That day we have a plant sale, children’s activities, book sales, science exhibits and much more. Last year we had over 1,000 people attend and they represented other countries, other states and 10 or so counties.
I appreciate that so many people come to my garden. They are happy to see what we have. Some of them are coming because they want to plant something in their own garden, and some are coming because they live in a place that doesn’t have anything green, so they come here to enjoy nature. Some of them say they have been pulling out certain weeds, and there are weeds certain butterflies use, such as grasses, stinging nettle—things that people wouldn’t want until they find out they are host plants for the butterflies.

What trends have you seen in the butterfly populations since you started monitoring them?
Early on, Ray Peterson, a lepidopterist from Audubon Canyon Ranch, said ‘your notes are very important’ because not that much is known about butterflies at this time—but I didn’t know I would see such a change. You can look at each species and see how many you saw and how few you are seeing each year.

With the drought—we were worried about the water. Since 2000 we saw butterfly numbers decreasing—the Anise and the Pipevine were low last year—and now the Anise is down this year, so far. We are beginning to see some come back. Every butterfly is different.

The Monarch upset us, we didn’t see it for two years; and then last year, we had a few in the early fall, but they kept laying eggs later than usual when their host plant, milkweed, was no longer available. We brought them inside and fed them what we could but the butterflies were not viable when they emerged from the chrysalis.

The Pipevine eggs hatch in about 10 days, depending on the weather. The caterpillars eat for about six weeks. Most of them hatch the next year.
The Monarch is different. The Monarch lays eggs that hatch in three weeks, and the caterpillars eat for three weeks and go into chrysalis for three weeks and fly away, while the Pipevine caterpillar could still be eating.

Why are butterflies important?
They are pollinators. We need plants that support them. Bees are having trouble, too. We are losing so much native habitat and wildlife in this area. My main hope is that I can keep the Gardens going as long as I’m here, and that the Garden’s board of directors will keep it going after I am gone.

When are you the happiest?
When you are seeing that what you’re doing in the garden helps… the birds, the deer, the butterflies and the other insects. I’m hoping that this little spot can continue this way. The butterflies and the other wildlife need this spot. SD