Skip to main content

Milkweed for Monarchs

May contain: plant

The RCD’s Milkweed for Monarchs program is all about creating more habitat for monarch butterflies and other pollinators by planting milkweed. Planting milkweed provides essential habitat for Monarchs, and also provides the opportunity to observe the life cycle of these fascinating insects.

Milkweed is the host plant for monarchs. Female butterflies lay their eggs on milkweed leaves, and it is the sole food source of monarch caterpillars. The number of monarch butterflies counted at overwintering sites in California and Mexico has decreased by about 95% since the 1980s! We also are experiencing a major loss of milkweed plants in monarchs’ spring and summer breeding areas, due to factors like urban and agricultural development and the use of herbicides in farming, pastures, and along roadways.

To help conserve this iconic species, we suggest including milkweed in any pollinator habitat planting, and we strongly encourage planting native milkweed instead of tropical or other non-native milkweeds. By native, we mean milkweeds that are found in our region – and San Diego County has several types of native milkweed. The most common, and commonly available, is Narrowleaf Milkweed (Asclepias fascicularis), though a few others can sometimes be found at some nurseries as well (such as Wooly Pod Milkweed (A. eriocarpa) and California Milkweed (A. californica)). These milkweeds are found in other parts of California too, and the vast majority of the native milkweeds currently commercially available in San Diego originate from seed collected in central or northern CA.

We believe that milkweed from our region will be more successful in plantings because it is better adapted to San Diego’s unique climate. The SDPA has worked to establish a San Diego seed source of native milkweed that can be used in pollinator habitat projects of all scales – from the home or school garden to restoration projects. See more info on San Diego Native Milkweed Project, and how you can get some free seed!

Milkweed Seed Sowing and Plant Care Instructions 
Milkweed Care:
  • Our leaflet on how to sow and care for milkweed seeds.
Planting Milkweed:

Citizen Science Programs:

Report your Monarch sightings to Journey North, a country-wide Monarch monitoring program. Check out their interactive map of sightings so far this year!

Download an overview of monarch citizen science programs here

Join the Milkweed for Monarchs iNaturalist project where you can contribute observations of Monarchs in your gardens. Click here to join.

More info about monarch conservation:

Monarch conservation information – Xerces Society

Monarch and Milkweed Resources 

Monarch and Pollinator Conservation:  

  • Butterfly Farms: Education and conservation organization and nursery all on one site. Come visit their butterfly free flight house and buy pollinator plants for your garden.  
  • Monarch Joint Venture: A national partnership of federal and state agencies, non-governmental organizations, businesses, and academic programs working together to conserve the monarch butterfly migration.  
  • Monarch Watch: A wealth of information about monarchs – creating habitat, citizen science, migration, biology, and more. 
  • The Xerces Society: An organization dedicated to the protection of wildlife through supporting invertebrates.  They offer information and resources about issues affecting pollinators and what you can do to help these vital insects, and their website has a section dedicated to conserving the Western Monarch.
Participate in Citizen Science! 

Journey North:

  • A country-wide monarch monitoring program. Report your monarch sightings and check out their interactive map of sightings so far this year!  

Xerces Society:

  • Offers two citizen science opportunities. Help collect data to monitor the status of overwintering monarchs along the California coast by participating in the West Monarch Count that takes place over Thanksgiving and the New Year. You can also contribute to efforts to better understand the breeding habitat of monarchs by entering your monarch and milkweed sightings through the Western Monarch Milkweed Mapper.
  • An overview of monarch citizen science contributions and programs across the United States, including information on how to get involved.  (link to document title Monarch citizen science overview)

RCD Milkweed for Monarchs iNaturalist project:

  • Join this project and contribute observations of monarchs in your gardens.
Join our mailing list