Laura Lovett
What could be more delightful than butterflies flitting around your garden? If you’d like to increase their numbers, there are some simple things you can do. Butterflies go through four life stages: the egg, larva (caterpillar), pupa (or chrysalis), and the adult stage—the butterfly. At each stage, specific needs must be met for the insect to progress toward the final adult form and begin the cycle anew. By selecting the right variety of native flowers that flourish in your microclimate, you can contribute significantly to supporting their populations.
This requires a bit of planning and use of native plants that cater specifically to their needs as pollinators and as caretakers of their young. All female moths and butterflies lay their eggs on what are known as host plants, which provide for their caterpillars needs once hatched. The plants provide caterpillars with food, shelter, and protection, and can be anything from a small weed to a tall oak tree. A number of butterfly species may use only one specific host plant. Well known specialists include the Monarch Butterfly (milkweed species), the Mission Blue Butterfly (lupine species) and the Pipevine Swallowtail (California Pipevine). Others are generalists and will gravitate to any number of diverse plants. In particular, shrubs and trees like willow, oak and plum support dozens of butterfly species.
Asclepias fascicularis
A great place to start your search for host plants is on Calscape. Each plant entry lists which butterflies and moths are likely to lay their eggs on that plant, so you can pick out a specific plant for a specific butterfly you would like to attract, or you can plant a wide variety of species that will provide sustenance to many. Butterflies love warmth and sunlight, so ensure their part of the garden has plenty of sun exposure throughout the day. Grouping flowers together makes them more visible and accessible to the visiting insects. Gardeners can also accommodate butterflies by providing large rocks in the sun for wing warming, a small water feature (or better yet, a permanent mud puddle), and an environment free of pesticides and herbicides.
Once planted, keep an eye out for signs of caterpillars on your host plants and remember—these plants are meant to be eaten! Because caterpillars feed exclusively on their host plants, they won’t harm the rest of your landscape. Don’t reach for pesticides when you see leaf damage; take a moment to identify what’s causing it. With luck, it will be hungry caterpillars fattening up before they transform into butterflies!
Plants that support a diverse array of butterflies are offered in the plant sales of the Marin Chapter of the California Native Plant Society. Support the Chapter by ordering some plants from our native plant sales in the spring or fall.
Trees and Shrubs
Low Form Coffeeberry, Frangula californica ‘Mounding Manchester’, host for Green, Gray or Common Hairstreak, Pale Swallowtail
Leather Oak, Quercus durata, host for California Sister, Mournful Duskywing, California Hairstreak
Twinberry, Lonicera involucrata, host for Chalcedon and Variable Checkerspots
Lupinus albifrons
Silver Bush Lupine, Lupinus albifrons, host for Acmon Blue, Silvery Blue, Arrowhead Blue, Sulphur Butterflies
Coastal Bush Lupine/blue form, Lupinus arboreus/blue form, host for Painted Lady, West Coast Lady, Silvery Blue, Acmon Blue, Sulphur Butterflies
Catalina Cherry, Prunus ilicifolia ssp. lyonii, host for Lorquin’s Admiral, Pale and Western Tiger Swallowtail
Ribes sanguineum
White and Pink-flowered Currants, Ribes sanguineum var glutinosum, host for Tailed Copper Butterfly
Snowberry, Symphoricarpos albus, host for Variable and Snowberry Checkerspot
Acer circinatum
Vine Maple, Acer circinatum, host for Mourning Cloak, Western Tiger Swallowtail
Wild lilac, Ceanothus species, host for Pale Swallowtail, California Tortoiseshell, Hedgerow Hairstreak, Brown Elfin, Echo Blue and Spring Azure Butterflies
Perennials
California Pipevine, Aristolochia californica, host for Western Pipevine Swallowtail
Checkerbloom, Sidalcea malviflora, host for Painted Lady, West Coast Lady, Common Checkered Skipper
Coast Buckwheat, Eriogonum latifolium, host for numerous Metalmark and Blue Butterflies, Gray and Coastal Green Hairstreak
Eriogonum nudum var. nudum
Naked Buckwheat, Eriogonum nudum, host for Acmon Blue, Blue and Gorgon Coppers, Mormon Metalmark Butterflies
Sulphur Buckwheat, Eriogonum umbellatum, host for numerous Metalmark and Blue Butterflies, Gray Hairstreak
Foothill Penstemon, Penstemon heterophyllus, host for Common Buckeye, Variable Checkerspot
Narrow-leaf Milkweed, Asclepias fascicularis, host for Monarch Butterfly
Sticky Monkeyflower, Diplacus aurantiacus, host for Common Buckeye, Chalcedon Checkerspot
Mugwort, Artemisia douglasiana, host for American and Virginia Lady Butterflies
Lathyrus vestitus
Pacific Pea Vine, Lathyrus vestitus, host for Acmon and Silvery Blues, Grey and Common Hairstreak, Orange Sulfur Butterflies
Wild Honeysuckle, Lonicera hispidula, host for Chalcedon and Variable Checkerspots
Cobb Mountain Lupine, Lupinus sericatus, host for Painted Lady, Sulphur Butterflies, Acmon Blue, Silvery Blue, Gray Hairstreak