Monarchs & Milkweeds

monarchs and milkweedsmonarchs and milkweeds

By Judith Irven, gardening expert, landscape designer and writer

Monarch Butterflies: Beautiful Garden Visitors  

The gorgeous American Monarch butterflies (Danaus plexippus), with their orange wings, black veining and a distinctive black and white checkered pattern around the margins, are instantly recognizable by gardeners and non-gardeners alike. As a defense against predators, Monarch butterflies contain unpalatable chemicals that can actually cause some birds to vomit! And their bold wing pattern is a well-known warning to hungry birds that they should not trifle with those Monarchs.

Milkweed Is Essential For Monarch Butterflies

By current estimates, the overall number of American Monarchs has fallen by 90% in the last decade. The decline of Monarchs is directly linked to the loss of milkweed plants in the wild. Milkweeds (all members of the genus Asclepias) are the host plants for Monarchs, meaning Milkweeds are the ONLY PLANT that Monarch larvae are able to eat, and the only plant where adult Monarch butterflies will lay their eggs.

What's contributing to the loss of milkweed plants across the country? Today, before beginning their spring planting, conventional farmers (those who do not use organic practices) will spray their fields with chemicals to eradicate weeds. Unfortunately, his practice also kills all the wildflowers, including the Milkweeds, that surround those fields. Also, as cities, towns, and neighborhoods expand, wild open meadows where native milkweed is typically found are disappearing. 

The good news is that our gardens can make a difference!

A Monarch Butterfly on Butterfly Weed (Asclepias tuberosa)A Monarch Butterfly on Butterfly Weed (Asclepias tuberosa)
A Monarch Butterfly on Butterfly Weed (Asclepias tuberosa)

The Amazing Monarch Migration  

The amazing life cycle of the American Monarchs. If we are to reverse the appalling decline of these butterflies, it is helpful to understand more about of the remarkable life story of the American Monarch.

Eastern Monarchs

In the summertime, Eastern Monarchs can be found all the way from Mexico to southern Canada, and from the Rocky Mountains to the Eastern seaboard. All across this huge land area, four or sometimes five generations of Monarchs are born in a single season!

Starting in September and October, all Eastern Monarchs, (with the exception of a few that use the Atlantic seaboard) undertake a single prodigious migration to reach their over-wintering destination, the Monarch Butterfly Biosphere Reserve, in Southern Mexico.

During this migration, these tiny creatures fly the most astonishing distances. Those that begin their journey in the Canadian Maritime provinces will travel nearly five thousand miles to reach their winter destination in Central Mexico. Butterflies begin their fall migration in September or October, and finally reach their overwintering sanctuary in November.

The following March, those same butterflies set out on their northbound trip. However, no individual butterfly flies all the way north: At successive stops along the way, the female monarchs lay eggs on milkweed plants, and the resulting caterpillars initiate the new generation of butterflies that continue the journey northwards. It is estimated that in the course of the entire summer, eventually four or five generations will be raised.

In early fall, the final generation of females store their food supply in preparation for their long flight back to Mexico, instead of producing more eggs. These butterflies are also programmed to fly south or south-west depending on their starting points, to reach this single destination.

Check out this wonderful interactive map to see the flight paths taken by the butterflies during their trip south in the fall, as well as how the successive generations that are raised on the way north in the course of a single summer.

Western Monarchs

Like their eastern counterparts, the Western Monarch butterflies also have a migratory life cycle. Their summer territory is to the west of the Rocky Mountains, where typically, they will hatch three generations at successive points along those fly-ways.

Every fall, the third generation of these butterflies is programmed head south-west to reach one of several over-wintering destinations along the west coast of California and western Mexico.

Non-Migratory Monarchs

Unlike the Eastern and Western populations, American Monarch butterflies that are found in Florida and along the Gulf Coast do not migrate. This minor population remains in this warm climate on a year-round basis.

How Can Our Gardens Make A Difference? Plant Milkweed!

If we are to stop the decline of the Monarchs, and encourage their population to rebound, we need to ensure that milkweeds and other nectar producing flowers are available for the butterflies at each breeding point along their journey!

Milkweeds are the critical link for rebuilding our Monarch populations. The larvae of the butterflies absolutely require milkweed to survive - its the only food they can eat! Plant plenty of Milkweeds where Monarch butterflies can lay their eggs. 

Adult butterflies love nectar-rich flowers to fuel their travels. Shasta Daisies, Blazing Star, Echinacea, Rudbeckia, Asters, ornamental Oregano, and Goldenrod are butterfly favorites in addition to Milkweed. 

Today the Milkweeds are starting to make a come-back all across the country. Organic and regenerative practices in agriculture are growing, and the USDA is offering incentives for farmers and ranchers to plant milkweed and other pollinator friendly plants. Gardeners are also rallying to help the beleaguered butterflies! Since Milkweeds make great garden plants, many gardeners and schools are planting them, and people with larger properties are planting milkweeds as part of a naturalized meadow. For this effort to be truly effective, Milkweed restoration is required at each and every breeding point of these wonderful migratory butterflies. Every garden and Milkweed plant counts!

monarch caterpilla on a tropical milkweedmonarch caterpilla on a tropical milkweed
A growing Monarch caterpillar hungrily gnaws on tropical milkweed.
Ice Ballet Swamp Milkweed (Asclepias incarnata)Ice Ballet Swamp Milkweed (Asclepias incarnata)
Ice Ballet Swamp Milkweed (Asclepias incarnata)

Add Milkweed Plants To Your Garden

Milkweed plants can be planted in spring or fall. Often, Milkweed can be slow to wake up from dormancy compared to other perennials in your garden. Follow our planting guide to learn more: How To Grow Milkweed

  1. Ice Ballet Swamp Milkweed, Asclepias incarnata, Photo Credit Darlene Williams

    'Ice Ballet' Swamp Milkweed is a staple of the butterfly garden, providing essential food, nectar and shelter to Monarchs at every life stage. Clouds of fragrant, bright-white blooms...

    Learn More
    Ice Ballet Swamp Milkweed Swamp Milkweed Ice Ballet Asclepias incarnata Ice Ballet
    As low as $13.32 Sale $12.65
    Per Plant - 3" Pot
    'Ice Ballet' Swamp Milkweed is a staple of the butterfly garden, providing essential food, nectar and shelter to Monarchs at every life stage. Clouds of fragrant, bright-white blooms also attract and support a crowd of other pollinators. While many Swamp Milkweeds make their homes in wetlands, 'Ice Ballet' thrives in drier soils. (Asclepias incarnata)
Butterfly Weed (Asclepias tuberosa)Butterfly Weed (Asclepias tuberosa)
Butterfly Weed (Asclepias tuberosa)

Grow Milkweed From Seed

Milkweed seeds require cold stratification. In most areas, when you plant seeds outside in the fall, seeds can go through the cold stratification process naturally. Learn more: How To Germinate & Grow Milkweed Seeds

  1. Orange Butterfly Weed Seeds, Asclepias tuberosa with bee

    Butterfly Weed (Asclepias tuberosa) is the famous orange milkweed species native from Canada to Florida. Needs fast-draining soil and full sun. Perennial...

    Learn More
    Butterfly Weed Seeds Butterfly Weed Asclepias tuberosa
    As low as $4.95 Sale $4.70
    Per Packet
    Butterfly Weed (Asclepias tuberosa) is the famous orange milkweed species native from Canada to Florida. Needs fast-draining soil and full sun. Perennial
  2. Pink Common Milkweed Seeds, Asclepias syriaca

    Common Milkweed (Asclepias syriaca) produces purple/pink flower clusters that wildflower gardeners love. Milkweed is one of the Monarch Butterflies’ favorite plants and will bring ...

    Learn More
    Common Milkweed Seeds Common Milkweed Asclepias syriaca
    As low as $4.95 Sale $4.70
    Per Packet
    Common Milkweed (Asclepias syriaca) produces purple/pink flower clusters that wildflower gardeners love. Milkweed is one of the Monarch Butterflies’ favorite plants and will bring many winged friends to your garden or meadow. It can be a challenge to grow but once established it will thrive for years to come and spread quickly. Perennial.
  3. Pink Swamp Milkweed Wildflowers, Asclepias incarnata, Swamp Milkweed Wildflower Seeds

    Swamp Milkweed (Asclepias incarnata) is a showier variety of Common Milkweed. It is extremely elegant, producing willowy foliage and pink blooms. It will also attract beautiful butte...

    Learn More
    Swamp Milkweed Seeds Swamp Milkweed Asclepias incarnata
    As low as $39.95 Sale $37.95
    Per 1 Ounce
    Swamp Milkweed (Asclepias incarnata) is a showier variety of Common Milkweed. It is extremely elegant, producing willowy foliage and pink blooms. It will also attract beautiful butterflies and hummingbirds to your garden or meadow. Perennial.
  4. Showy Milkweed Seeds, Asclepias speciosa

    Similar to Common Milkweed in looks, Showy Milkweed has soft, pastel pink flower clusters with longer petals. This sun-loving asclepias grows well in dry, fast-draining soil and requ...

    Learn More
    Showy Milkweed Seeds Showy Milkweed Asclepias speciosa
    $5.95 Sale $5.65
    Per Packet
    Similar to Common Milkweed in looks, Showy Milkweed has soft, pastel pink flower clusters with longer petals. This sun-loving asclepias grows well in dry, fast-draining soil and requires little supplemental water once established. A prolific and important nectar source for Monarch butterflies, bees, and other beneficial bugs. Re-seeds readily. (Asclepias speciosa)
© 2021 AmericanMeadows.com All rights reserved