U.S. Fish & Wildlife Service

Sacramento Fish & Wildlife OfficeServing the people, conserving the fish, wildlife, and plants of California

A Unit Of The Pacific Southwest Region

What's in Your Garden?

September 27, 2017

Female monarchs only lay eggs on milkweed plants because monarch caterpillars only eat milkweed.

Female monarchs only lay eggs on milkweed plants because monarch caterpillars only eat milkweed. Photo credit: John Cleckler.

Habitat is important to animal and plant species—whether or not they are federally listed. Throughout Northern California, people are supporting wildlife by planting gardens that include native plants, a diverse array of nectar and pollen sources, and avoid or limit pesticide use. These efforts help all wildlife, including pollinators that are so critical to the food supply in the United States.

It will take between 28-38 days for this monarch butterfly egg to complete metamorphosis and emerge as an adult butterfly.

It will take between 28-38 days for this monarch butterfly egg to complete metamorphosis and emerge as an adult butterfly. Photo credit: John Cleckler.

Below is Wildlife Biologist John Cleckler’s first-hand account about a recently established rain garden that created habitat suitable for monarch butterflies.

Yesterday morning my son drew my attention to a couple of monarchs flying around in the front yard. This made me very excited because they were the first I've seen visiting the rain garden I created last summer. I made a rain garden to collect storm water. Planted a few milkweed species in it to specifically attract monarchs. I'd given up hope of visitors for this year. But, we were lucky enough to catch at least one monarch landing on a couple of showy milkweed plants (Asclepias speciosa), extending her abdomen to the underside of the leaves to oviposit (lay eggs) individual eggs. Later I inspected the leaves and found several eggs.

Life cycle summary

  • The eggs should hatch within a week.
  • The caterpillars (or larvae) will go through a couple of stages (instars) as they eat their way to maturity, feeding exclusively on milkweed.
  • After 2 or 3 weeks of fattening up it will be time for them to attach themselves to something nearby and form their chrysalis (cocoon).
  • Then, about 2 weeks before the wrinkly new butterfly emerges, pumps "body fluid" to expand its wings, and takes flight.

John Clecker is a Sacramento Fish and Wildlife Office biologist.

Learn more

John's children help him maintain the rain garden

John's children help him maintain the rain garden. Here
his daughter gets a closer look at a monarch egg left behind on the milkweed they planted. Photo credit: John Cleckler.

Rain gardens are becoming more common in residential areas as an effective use for storm water runoff. Photo credit: John Cleckler.

Last updated: November 8, 2017