Monarch butterfly
Danaus plexippus
CA Special Concern
California Species of Special Concern; monarch populations declining
Large orange butterfly with bold black veins and white spots. Famous multi-generational migrant; critical stopover habitat needed for Bay Area populations. Milkweed caterpillars sequester plant toxins for predator protection.
Plants that support Monarch butterfly
48 plants
American Cow-parsnip
Heracleum maximum
perennial herb
Important nectar source for migration fuel; used during spring northward migration Mar-May
American-hemp
Apocynum cannabinum
perennial herb
Critical larval host plant for California populations; caterpillars feed on milkweed family plants including A. cannabinum
Amphibious Bistort
Persicaria amphibia
perennial herb
Host plant for caterpillars in wetland breeding populations
Bearbind
Calystegia sepium subsp. limnophila
vine
Critical nectar source for spring and fall migrations through California; fueling for long-distance movement
Blue Field Gilia
Gilia capitata
annual
Critical spring migration fuel (northbound) and fall pre-migration energy source (southbound)
Blue Flax
Linum lewisii
perennial herb
Larval food plant for multiple generations; critical during spring/fall migration corridors
Branching Phacelia
Phacelia ramosissima
perennial herb
Spring migration fuel source in California, energy for northbound movement
Brewer's Ragwort
Packera breweri
perennial herb
Early spring nectar source for migrating populations returning to California
California Aster
Symphyotrichum chilense
perennial herb
Critical fall migration fuel source Sep-Nov during southbound migration to Mexico
California Aster
Corethrogyne filaginifolia
perennial herb
Fall migration staging fuel September-October; critical nectar source for long-distance migrants
California Buckeye
Aesculus californica
tree
Spring migration nectar source, May-Jun bloom provides critical fuel
California Buckwheat
Eriogonum fasciculatum
shrub
Critical fall migration fuel source Aug-Oct for southbound populations
California Goldenrod
Solidago velutina ssp. californica
perennial herb
Critical fall migration fuel source Sep-Oct during southbound migration to Mexico
California Milkweed
Asclepias californica
perennial herb
Critical larval food plant for multiple generations; essential for spring and fall migration populations
California Poppy
Eschscholzia californica
annual
Spring northbound migration (Feb-Apr) and fall southbound migration (Aug-Oct) fueling; critical staging resource
California sunflower
Helianthus californicus
perennial herb
critical nectar source during fall migration staging Sep-Oct
Chaparral Currant
Ribes malvaceum
shrub
Critical fall migration fuel source Sep-Nov heading to overwintering sites
Coastal Moonshine
Deinandra corymbosa
annual
Critical nectar source during fall migration staging (Aug-Oct)
Common Pearlyeverlasting
Anaphalis margaritacea
perennial herb
Critical fall migration fuel source during southbound movement Sep-Oct
Common sunflower
Helianthus annuus
annual
Critical fall migration nectar Aug-Oct for southbound populations
Coyote Brush
Baccharis pilularis
shrub
Critical fall migration staging nectar Sep-Nov
Coyote Mint
Monardella villosa
shrub
Critical fall migration fuel Aug-Sep for southern migration
Creeping Sage
Salvia sonomensis
shrub
Larvae feed on milkweed species; adults use Salvia as nectar source during spring migration and fall breeding
Distant Phacelia
Phacelia distans
annual
Nectar source during spring breeding and fall migration staging
Douglas's False Willow
Baccharis glutinosa
perennial herb
critical fall migration fuel source Sep-Oct during southbound migration to Mexico
Hairy gumplant
Grindelia hirsutula
perennial herb
Critical fall migration fuel source during southbound migration (Aug-Oct)
Hummingbird Sage
Salvia spathacea
perennial herb
Spring migrant nectar source during northward migration
Madrone
Arbutus menziesii
tree
Spring/fall migration nectar resource
Mountain Coyote Mint
Monardella odoratissima
perennial herb
Northbound migrants April-May; critical refueling nectar
Mulefat
Baccharis salicifolia
shrub
Critical fall migration fuel source Sep-Oct during southbound migration to overwintering sites
Narrow-leaf Milkweed
Asclepias fascicularis
perennial herb
Critical larval host plant throughout CA growing season Jun-Sep; spring/fall migration staging resource
Nootka Rose
Rosa nutkana
perennial herb
Spring migration and breeding season nectar source
Red Willow
Salix laevigata
shrub
Occasional adult nectar source in California, not primary milkweed host
Red-Osier Dogwood*
Cornus sericea subsp. sericea
shrub
Late-season nectar source for fall migration fuel-up; important at riparian oases Aug-Oct
Rubber Rabbitbrush
Ericameria nauseosa
perennial herb
Important nectar source during fall migration staging Sep-Oct in western populations
Seaside Heliotrope
Heliotropium curassavicum
perennial herb
Critical host plant for monarch caterpillars during spring-fall migration periods; essential for population maintenance
Showy milkweed
Asclepias speciosa
perennial herb
Essential larval food plant for multiple generations; critical during spring northward migration (Feb-Apr) and fall southward migration (Aug-Oct)
Suisun Marsh Aster
Symphyotrichum lentum
perennial herb
critical fall migration fuel source Sep-Oct for southbound monarchs
Sulfur Buckwheat
Eriogonum umbellatum var. bahiiforme
perennial herb
Occasional visitor to flowers during fall migration staging; supplemental nectar source
Western Azalea
Rhododendron occidentale
shrub
Migrant nectar source during summer dispersal and fall migration staging
Western Redbud
Cercis occidentalis
tree
Spring migrants and breeding generation utilize early nectar March-May
Western goldenrod
Euthamia occidentalis
perennial herb
Critical fall migration fuel source Sep-Oct during southbound migration to overwintering sites
Whiteleaf Manzanita
Arctostaphylos manzanita subsp. laevigata
shrub
Spring migration stopover; critical nectar source for northbound populations
Woolypod milkweed
Asclepias eriocarpa
perennial herb
Critical larval foodplant for multiple generations; adults also nectar on flowers
Yarrow
Achillea millefolium
perennial herb
Critical fall migration fuel source Sep-Oct during southbound migration to Mexico
Yellow Coastal Bush Lupine
Lupinus arboreus
perennial herb
Spring migration fuel stop in coastal California