To help maintain the diversity of native plants in the region and stem their risk of extinction, a La Jolla resident has cultivated a new native seed library.

Mary Mitchell, a member and former president of the La Jolla Garden Club, established the library at 5558 Soledad Mountain Road about two months ago.

The wooden structure is similar to a Little Free Library, but instead of resembling a house or bookshelf, the “Soledad Mountain Seed Library” is shaped like a butterfly. And instead of being full of books, its “wings” open to reveal drawers filled with packets of plant seeds and literature on the plants and the insects and birds that encourage plant growth through pollination.

“I would like to help nature a little bit,” Mitchell said.

Visitors to the seed library can take a packet of seeds, plant it on their property and tend to its growth.

Once the plant has matured, the visitor harvests new seeds to return to the seed library.

Mitchell built the seed library — fashioned after the extinct Xerces blue butterfly — after learning about such libraries through her membership in San Diego Audubon, a nonprofit conservation group.

San Diego Audubon, in partnership with the California Native Plant Society, began its native plant seed library program nearly two years ago to promote biodiversity. The seed library network now has more than 30 locations in San Diego County.

There are two such libraries in La Jolla — Mitchell’s and one at the La Jolla/Riford Library on Draper Avenue, which a local student created last summer.

San Diego Audubon sent Mitchell her first set of seeds and Mitchell supplied the rest. There are currently six types of seeds in the Soledad Mountain Seed Library: California poppy, California buckwheat, coastal goldenbush, narrow-leaf milkweed, sea dahlia and yellow evening primrose.

Each packet contains just an eighth of a teaspoon of seeds, Mitchell said, “but that’s more than enough.”

She said she’s had to replenish the seed packets a couple of times and hopes the idea continues to grow.

San Diego County is a “hot spot,” Mitchell said, meaning it’s “a place with lots of diversity which is at risk. San Diego has more diverse plant and animal species than any other county in the continental U.S.”

It also has more plant and animal species that are threatened with extinction than anywhere else in the country, she said.

“Diversity helps to maintain a healthy and unique environment that many think we should work to preserve,” Mitchell said. ◆