Conserving Monarchs: Steps You Can Take in Your Phoenix Community to Support Butterfly Migration

The migratory path of Monarch butterflies occurs in Phoenix during their annual journey between their overwintering sites in Mexico and their breeding grounds in the northern United States and Canada. Monarchs undertake this remarkable journey spanning thousands of miles, and along the way, they rely on various resources, including nectar-rich flowers and specific host plants like milkweed.

The Monarchs develop from egg to adult in about 4 weeks:

• Eggs hatch in about 4 days. Females lay one egg on a plant; in their lifetime they will lay 100-300 eggs.
• Caterpillars go through five instars in about 14 days. When they first hatch, caterpillars eat the egg shell for nourishment. Similarly, they eat shed skin after every molt.
• Chrysalis stage is about 14 days

The overwintering generation lives about eight months due to a biologic change that stops reproductive behavior during their migration south. The summer generations of the butterfly live only three to five weeks.

A pollinator garden in Phoenix can play a crucial role in supporting Monarch butterflies during their migration. These gardens are designed to provide habitat and food sources for pollinators, including butterflies, bees, and hummingbirds. By planting a diverse array of native flowering plants, particularly those that bloom during the Monarchs’ migration season, gardeners can attract and support these magnificent butterflies.

Monarchs have a strong affinity for milkweed plants, as they serve as the sole host plants for their caterpillars.

Female Monarchs lay their eggs exclusively on milkweed leaves, and the emerging caterpillars feed voraciously on the plant.

The presence of milkweed in a pollinator garden greatly enhances its attractiveness to Monarchs, providing a vital resource for their breeding and reproduction.

In terms of preferences for specific species of milkweed, Monarchs exhibit varying preferences based on their geographic location, migratory path and availability of different milkweed species. In the Phoenix, a few species of milkweed are commonly found. These include the Desert Milkweed (Asclepias subulata), Showy Milkweed (Asclepias speciosa), Narrowleaf Milkweed (Asclepias fascicularis) and Butterfly Weed (Asclepias tuberosa).

While Monarchs generally show a preference for native milkweed species, they can adapt to utilizing non-native species as well. However, it is important to note that native milkweed species are typically better adapted to local climates and provide a more sustainable habitat for Monarchs and other pollinators. See also Milkweeds in the Sonoran Desert.

The presence and abundance of these and other milkweed species along the migratory path can impact the preferences of Monarchs. The availability of suitable milkweed species plays a significant role in determining the success of Monarch breeding and reproduction along their journey.

Additionally, native milkweed species often have co-evolved relationships with Monarchs, offering optimal nutritional content and defenses against predators and parasites.

To create a pollinator garden that attracts Monarchs, incorporate a mix of native milkweed species along with other nectar-rich flowering plants. This not only provides essential food for Monarch caterpillars but also offers adult butterflies a diverse range of nectar sources during their stopovers in Phoenix.

Overall, by creating a pollinator garden with a variety of native milkweed species and nectar-rich flowers, you can contribute to the conservation of Monarch butterflies and support their migration journey by providing vital resources along their migratory path.