Don’t be misled by the name “milkweed”; it’s far from being just a common weed. This robust native plant, found across North American fields, wetlands, and prairies, is critical for the survival of the endangered monarch butterfly, which relies on it exclusively during its larval stage.
Milkweed patches in the summer are vibrant and buzzing with life. The air is fragrant, bees hum diligently, and you might catch sight of a monarch butterfly fluttering from blossom to blossom or find its caterpillars nibbling on the leaves. Despite its unfortunate nickname, milkweed is gaining recognition for its ecological importance and aesthetic value.
In fact, in 2017, the butterfly weed—a type of milkweed—was named the Perennial of the Year by the Perennial Plant Association, spotlighting its role not only as a beautiful garden plant but also as a vital part of our ecological landscape.
The past six years have seen a marked increase in the interest in native plants and their crucial relationships with native insects, thanks to advocacy and informative articles like those from The Garden Shed since 2016. The most notable of these relationships is between the milkweed and the monarch butterfly.
Recently, on July 21, 2022, the monarch butterfly was declared “endangered” by the International Union for the Conservation of Nature, emphasizing the need for habitat conservation efforts like planting milkweed.
Historically, milkweed has been utilized by both humans and wildlife in numerous ways. Native Americans, for example, harvested it for food and medicinal purposes, and crafted twine and rope from its fibrous stems. The fluffy seed linings, known for their insulating properties, were used in household items like mattresses and winter clothing.
Although milkweed is sometimes viewed as a nuisance by farmers due to its toxicity to livestock, its environmental benefits, particularly for monarchs, outweigh these challenges.
The decline in milkweed habitats has directly impacted the monarch population, stressing the importance of cultivating these plants in domestic gardens. Planting milkweed is simple and can significantly aid in the recovery of these butterflies.
In this article, we’ll explore how to select and cultivate the right milkweed species for your local area, leveraging native plant databases to ensure regional compatibility. I’ll share insights on growing milkweed from seeds and discuss the suitability of various species for specific garden conditions.
We’ll also touch upon the latest research concerning tropical milkweed and its implications for local ecosystems. By the end, you’ll be equipped to start your own monarch butterfly haven right in your backyard.
Milkweed Basics
Milkweed, belonging to the Asclepias genus, includes a variety of flowering perennials found across the United States, as well as in parts of Canada and Mexico. With over 70 species indigenous to the U.S., each of the lower 48 states boasts its own native milkweed, about 30 of which serve as crucial habitats for monarch butterflies.
These plants are named for their distinctive, milky sap that emerges from the leaves when they are injured. The U.S. and Canada are home to more than 100 types of this herbaceous perennial, notable for their ecological importance and ornamental value.
When considering milkweed for your garden, there are three species particularly suited to most American regions:
- Common milkweed (A. syriaca)
- Swamp milkweed (A. incarnata)
- Butterfly weed (A. tuberosa)
Both swamp milkweed and butterfly weed offer a range of visually appealing cultivars. However, it’s wise to steer clear of tropical milkweed (Asclepias curassavica), a non-native species that can negatively impact monarch populations.
Milkweeds adapt to a variety of environments, from wet marshes to dry forests, and can even thrive in less ideal locations like roadside verges.
They vary in height, leaf shape, and the vibrant spectrum of their blooms—from whites and yellows to deep purples and fiery reds. However, all share a unique floral structure: a crown of five hoods above a ring of five petals.
Handling most milkweed species requires caution due to the skin-irritating sap, except for the Butterfly Weed. It’s advisable to wear gloves for your safety.
From an ecological standpoint, milkweeds are vital, supporting a diverse range of insects and even some hummingbirds, who depend on the plant for nectar. Their small, star-shaped flowers are engineered for efficient pollination, and come fall, their large seed pods burst open, dispersing hundreds of seeds, thereby ensuring the continuation of the species.
Typically, milkweeds grow between two to five feet tall and are suitable for zones 3 through 9, making them a versatile and beneficial addition to many gardens.
Why Choose Milkweed for Your Garden?
Absolutely, milkweed is a fantastic choice for garden landscapes! This versatile plant effortlessly fits into various garden styles, thanks to the abundance of native species available. It’s especially easy to incorporate into landscapes in areas where milkweed naturally thrives.
North and Central America are home to over 100 native milkweed species that provide essential shelter, nesting habitats, and food for numerous animals. Milkweed is particularly vital for over 450 insect species, including various butterflies and bees that are drawn to its nectar-rich blooms.
Notably, it’s a crucial plant for monarch butterflies at every life stage—caterpillars feed exclusively on milkweed, which is also a host plant for other insects like the tussock moth and ladybugs.
The alarming decline in monarch butterfly populations has spurred many conservation efforts focused on planting more milkweed. However, it’s not just monarchs that benefit. Milkweed serves as an excellent nectar source for many bee species and hummingbirds too.
In addition to its ecological benefits, milkweed helps to beautify gardens with its native charm. It’s a staple in American wildflower gardens, suitable for most U.S. regions. Frequent visitors include not only monarchs but also native bees, honey bees, hummingbirds, and various butterflies.
Monarchs specifically depend on milkweed to reproduce, laying eggs exclusively on these plants from spring to early fall. This results in multiple butterfly generations each year. Once hatched, the monarch caterpillars munch on milkweed leaves for about two weeks before transitioning into chrysalises.
Adult monarchs also rely on milkweed flowers for nectar, along with other native wildflowers. The toxic compounds in milkweed, called cardenolides, are harmful to many but not to monarchs, who have evolved to tolerate and even benefit from these toxins.
These compounds accumulate in the monarchs, providing a vital defense mechanism against predators.
Milkweed is indispensable not just as a food source but as the sole host plant for monarchs, crucial for their survival and reproduction. Thus, incorporating milkweed into your garden supports not only the aesthetic appeal but also the local ecosystem, particularly aiding in the conservation of these beautiful butterflies.
Why are milkweed and monarch butterflies declining?
The loss of milkweed and monarch butterflies can be attributed to several human activities and environmental changes. One significant factor is deforestation and development: the expansion of agricultural lands and urban areas often involves cutting down forests and transforming rural landscapes.
This not only strips away the winter habitats of monarch butterflies but also reduces the milkweed plants they rely on during their migration.
The use of chemicals in managing landscapes and agriculture is another major culprit. Herbicides aimed at controlling unwanted plants along roadsides and in fields decrease milkweed availability nationwide.
Furthermore, pesticides designed to protect crops can inadvertently harm or kill monarchs and other migrating insects. Systemic pesticides, like neonicotinoids known for their detrimental effects on bees, are particularly harmful as they integrate into a plant’s system, causing prolonged toxicity.
Commercial nurseries contribute to the problem by selling plants treated with these systemic pesticides. Unsuspecting gardeners may plant these in their gardens, unintentionally poisoning visiting monarchs. Additionally, aggressive practices such as extensive roadside mowing drastically reduce milkweed along migration paths.
Climate change exacerbates these issues through various mechanisms. Drought conditions stunt milkweed growth and contribute to wildfires that destroy these plants.
Elevated temperatures may prompt monarchs to migrate prematurely, before sufficient milkweed is available for nesting and feeding. Such adverse weather conditions have led to the death of millions of monarchs.
Efforts to replenish milkweed stocks are also struggling due to limited availability of seeds and plants. Of the 70 native milkweed species in the U.S., fewer than 20 are commonly sold by commercial growers, and availability remains particularly low in regions critical to monarch conservation, like much of the Western U.S.
Moreover, the introduction of tropical milkweed, Asclepias curassavica, poses its own set of problems. While attractive and easy to grow, this non-native plant can be detrimental. It harbors parasites that infect monarch caterpillars and encourages breeding at inappropriate times due to its year-round presence.
Recent studies suggest that climate change may increase the toxicity of tropical milkweed, posing additional risks to monarchs. Thus, while well-intentioned, planting tropical milkweed instead of native varieties can inadvertently harm monarch populations.
How to Grow Milkweed in Your Home Garden
You have two main options when it comes to growing milkweeds: buying established plants or starting them from seeds. If you’re eager to see blooms quickly, opting for pre-rooted plants is your best bet, as they will flower much sooner.
However, if you need many plants, growing them from seeds is more cost-effective. Keep in mind that milkweed seeds often require a chilling period to germinate.
To do this, first remove any fluff from the seeds, then wrap them in a moist paper towel, place them in a labeled and dated plastic bag, and refrigerate for about 30 days. Once chilled, the seeds are ready to be planted in your chosen containers and grown until they’re robust enough for your garden.
It’s also crucial to choose the right type of milkweed for your area. Native species are generally recommended because they align with the local ecosystem and support natural pollinator pathways. Non-native species, on the other hand, might interfere with these pathways and negatively affect local pollination.
To find the best milkweeds for your region, visit a local native plant nursery or look for reputable suppliers online. Remember, seedlings typically take three seasons to flower, so patience is key when starting from seeds.
Optimal Locations for Planting Milkweed
When considering where to position milkweed in your garden, it’s crucial to select sunny locations that get a minimum of six to eight hours of sunlight daily. To manage their tendency to spread, place them strategically—perhaps along the back borders or tucked into garden corners.
Opt for a location that’s shielded from strong winds to minimize seed dispersal and create a welcoming spot for visiting butterflies. Remember, milkweed has a deep taproot, making it tricky to relocate once established.
For optimal growth, milkweed thrives in sunny, sheltered spots. This not only curbs the scattering of seeds by the wind but also ensures a cozy spot for monarch butterflies. It’s smart to plant milkweed near viewing areas like windows or benches, allowing you to enjoy the spectacle of fluttering monarchs and other pollinators up close.
Consider placing milkweed around the periphery of your garden, especially in areas that receive full sunlight. Grouping them at garden corners or using them as a border can enhance accessibility for monarchs, as isolated plants are easier for them to spot.
Ensure the site is reachable from multiple directions to increase butterfly visits. Milkweed prefers well-draining soil, so amend clay-heavy soil with peat to avoid root rot.
Where should you avoid planting milkweed? Steer clear of shaded areas or places with poor drainage. Most milkweed species, except for swamp milkweed, require well-drained soil to prosper. Also, avoid planting milkweed in non-native regions, particularly certain coastal areas, as this can interfere with the monarchs’ migratory patterns and nesting habits.
In regions where milkweed is non-native, consider planting alternative nectar-rich plants like coneflowers, yarrow, goldenrod, Joe-Pye weed, black-eyed Susans, and asters. These plants support a broad range of pollinators and are beneficial for attracting and sustaining monarch populations.
When to plant
If you’re keen on growing milkweed from scratch, planting the seeds outside during autumn is your best bet. This timing exposes them to the cold, damp conditions they need to kickstart their growth come spring, leading to a vibrant bloom in summer.
For those opting for pre-grown seedlings, aim to get them in the ground once the threat of frost is behind you. Here’s a tip for seed lovers: spread them evenly over the ground and press them into the earth using either your foot or a trowel.
While autumn is ideal, planting in early spring is also feasible if it’s still chilly—cold weather helps with seed germination. In drier regions like the Southwest, try to plant right before an expected rain to help the seeds settle in.
Remember, it might take a year before you see any blooms, but the local monarch butterflies will appreciate your effort right away. When it comes to seedlings, plant them after the last frost of spring to dodge any sudden, harsh weather. Be sure to give them a good watering after you plant them to help them settle into their new home.
Choosing the right soil for milkweed
Choosing the right soil for milkweed depends largely on the specific variety and its natural habitat. Many types of milkweed are quite adaptable and will flourish in the typical soil found in most gardens.
However, swamp milkweed is a special case; it thrives in wet, nutrient-rich soil. For optimal growth, milkweed prefers soil that drains well. If you’re dealing with clay-heavy soil, mixing in some peat can prevent root rot by improving drainage.
If you’re keen on starting from scratch, you might consider planting milkweed seeds indoors. Simply plant the seeds in damp soil, cover them with plastic wrap, and chill them in the refrigerator for three weeks.
Once this period is up, take them out and keep them inside, giving them a light misting now and then, until it’s warm enough to move them outdoors. This indoor method requires more effort and attention compared to direct outdoor planting.
Planting milkweed
Planting milkweed seeds successfully starts with preparing a fine, smooth soil bed. Use a rake or a rototiller to break up any clumps and create a soft planting surface. Once you’ve scattered the seeds, press them lightly into the earth to ensure solid contact between the soil and seeds, but be sure not to bury them.
Keep the soil evenly moist to help the seedlings get a strong start. As they grow, thin out the crowd—remove any seedlings that are too close to their neighbors to prevent competition for sunlight and nutrients.
Milkweed plants are sensitive in their early stages, especially their roots. When planting, be gentle and maintain the depth at which the plant was originally grown in its pot.
Choose well-draining soil and water the plants consistently until they’re firmly established, but avoid waterlogging the soil. Also, keep an eye on surrounding vegetation to prevent overcrowding.
Remember, planting a variety of milkweed species—ideally two or three native to your area—can extend the blooming period as different species flower at varying times. This staggered blooming keeps your garden lively throughout the growing season. Aim to plant at least three of each species to create a thriving habitat.
Lastly, allowing the seed pods of milkweed to drop and disperse can transform your garden. Before long, you’ll find multiple milkweed plants flourishing where they fall, contributing to a vibrant ecosystem and supporting local wildlife like the monarch butterfly. Remember, “More plants make for merry monarchs!”
Spacing
If you’re eager to see your garden become a haven for monarch butterflies, consider planting clusters of milkweed, with each group containing at least six plants. Space these out by 6 to 24 inches, tailored to the type of milkweed you choose.
Monarch butterflies have a knack for spotting these plants, and the more milkweed you have, the better your chances are of them visiting and depositing eggs. So, go ahead and plant as many as your garden space allows!
Milkweed tends to spread, forming expansive colonies through its roots and seeds, particularly in meadow-like or wildflower settings where they can grow freely. However, in smaller garden spaces, especially when planting varieties like common milkweed, you’ll need to manage its growth.
Prevent unwanted spreading by removing seed pods before they burst open and release their seeds. For those plants that spread through their root system, consider planting them in a raised bed or a container that’s embedded in the ground to contain their growth. This way, you can enjoy the beauty and ecological benefits of milkweed without it taking over your garden.
Propagating
You can easily propagate various milkweed species using either root or rhizome cuttings, or by planting seeds. The best time to take these cuttings is in late fall or early spring, when the plants are dormant and their energy stores are highest. Once planted, these cuttings will sprout new growth as temperatures rise, and they usually bloom within their first year.
Milkweed Care
Milkweed is notably tough against challenges like heat, drought, and pests such as deer. This hardy plant is native and well-adapted to less fertile soils, eliminating the need for additional fertilization.
- Is milkweed simple to maintain?
Absolutely! Especially if you choose a species native to your area, milkweed is quite low-maintenance. It can withstand harsh conditions including poor soil, without the need for fertilizers.
- Mulching Tips:
While mulching can help control weeds and maintain moisture, not all milkweed varieties benefit equally. For instance, swamp milkweed does well with moisture-retaining mulch, whereas varieties like common milkweed and butterfly weed prefer drier conditions and usually do better without mulch.
- Pruning Practices:
Trimming fading milkweed blooms can extend their blooming period, enhancing both their beauty and their utility as a habitat for monarch butterflies. By cutting back spent flowers just above a leaf node, you promote new growth and continued nectar production.
Pruning also helps thin out the plants, allowing better air circulation, crucial before and after the monarch breeding season.
- Staking Needs:
Milkweed possesses sturdy stems that naturally support themselves, so staking is not necessary.
- Watering Requirements:
Swamp milkweed needs moist soil or frequent watering, whereas drier varieties like common milkweed and butterfly weed thrive with little to no watering once established.
- Fertilizing:
Given its tolerance for poor soil, milkweed generally does not require added fertilizers.
- Dividing and Transplanting:
It’s best to avoid dividing or transplanting milkweed as it develops a deep taproot system that prefers not to be disturbed once settled.
- Managing Pests:
Milkweed can attract certain pests like aphids and milkweed bugs, which are resistant to its natural toxins. However, these pests seldom cause serious harm. Physical removal using soapy water can effectively manage these pests without harming beneficial insects.
Always identify pests accurately before taking action, possibly consulting your local extension office for assistance, and opt for environmentally friendly pest control solutions.
- Controlling Overgrowth:
To prevent milkweed from overtaking your garden, remove or securely tie its seed pods in autumn to stop them from dispersing seeds. For varieties that spread through rhizomes, it’s best to pull these plants by hand when they’re young, ensuring you remove as much of the root system as possible.
- Safety Tips and Plant Toxicity:
Handling milkweed requires caution due to the toxic alkaloids in its sap, which can irritate the skin and eyes and are harmful if ingested by pets or humans. Despite its potential dangers, the bitter taste of the plant usually keeps animals and children at bay. Always wear gloves and protective clothing when dealing with milkweed to avoid irritation.
- Creating a Butterfly Haven:
Enhance your garden’s appeal to butterflies by planting milkweed alongside other nectar-rich native plants. Include varieties like asters and goldenrods that bloom in the fall, as well as native grasses and alliums, which help deter pests and provide a habitat for various pollinators.
- Avoiding Chemicals:
Never use pesticides on or around milkweed, as these chemicals pose a significant threat to monarch butterflies and other vital insect species. Opt for natural pest control methods to keep your garden safe and supportive of local wildlife.
Selecting the Right Milkweed Varieties
Milkweed is commonly discussed as a singular type, but it actually comes in various species, each with unique flowering times and appeals to different pollinators.
For example, orange butterfly milkweed and whorled milkweed are favorites among native bees, whereas swamp, common, and showy milkweed varieties are more likely to attract larger bees like bumblebees.
When choosing milkweed, it’s crucial to opt for varieties that are native to your region. These native plants not only support local wildlife but are also easier to grow since they’re adapted to your local climate. Typically, if you source your milkweed from a local gardening group or a conservation organization, they would have already identified the native species for you.
Common milkweed (Asclepias syriaca)
Among the well-known types, common milkweed, or Asclepias syriaca, is prevalent across the eastern United States and southern Canada. It grows up to five feet tall and is sturdy enough not to require staking.
This species is often found in natural settings like fence rows and along roads but is also a stellar addition to gardens due to its impressive clusters of sweet-scented, pinkish flowers that bloom from June to August. The ornamental pods, which start green and turn brown as they mature, add another layer of interest.
This milkweed thrives in full sun and well-drained soils, and its presence is common in pastures and along roadsides. It blooms profusely from June to August, displaying large clusters of dusty pink flowers.
This plant is fast-spreading and is considered less decorative by some, making it ideal for larger areas where it can grow freely without constraints. For smaller spaces, consider confining it to a raised bed or regularly removing its seed pods to prevent widespread dispersal.
Swamp Milkweed (A. incarnata)
Swamp milkweed, or A. incarnata, is another attractive option, particularly for moist environments. This species boasts beautiful rose-purple flowers and does well in heavy clay soils, though it requires ample moisture to thrive. It’s a perfect choice for planting near water bodies or in rain gardens.
Varieties like ‘Ice Ballet’, ‘Soulmate’, and ‘Cinderella’ offer delightful blooms in shades of pink and white. Swamp milkweed prefers full to partial sun and grows best in wet, acidic to neutral soils. Despite its spreading through rhizomes and seeds, it’s not overly aggressive, making it a great addition to perennial gardens.
Purple Milkweed (A. purpurascens)
Purple milkweed, A. purpurascens, resembles the common variety but features more intensely colored blooms from late spring to early fall. It’s a less aggressive spreader and is best suited for perennial gardens.
Found mainly along woodland edges, this species thrives in less organically rich soils and benefits from partial shade. Though not as readily available commercially, purple milkweed can be sourced from native plant nurseries or online seed suppliers.
Butterfly Weed (A. tuberosa)
Known for its vibrant orange flowers, Butterfly Weed stands out as it doesn’t release irritating sap when cut. It thrives in dry, open areas like prairies and is a staple in many gardens across the U.S. from Maine to Florida. Its modest height makes it perfect for border planting, and unlike other milkweeds, it has a watery sap.
This plant is tough, prefers full sun, and is excellent for attracting a host of pollinators. It’s also deer resistant but might attract rabbits. Butterfly Weed is commercially available and grows well in poor, dry soil.
Showy Milkweed (Asclepias speciosa)
Ideal for gardens in the Western and Upper Midwest U.S., Showy Milkweed sports larger pink or purple flowers compared to its cousins and is less invasive. It’s especially effective at attracting monarch butterflies, making it a favorite among gardeners in these regions.
Whorled Milkweed (A. verticillata)
This variety does well in both the Eastern U.S. and parts of the West. It features delicate greenish-white flowers and is suited to dry, nutrient-poor soils.
Whorled Milkweed blooms from June through September and isn’t as aggressive in spreading, making it suitable for rock gardens and arid hillside plantings. It attracts various nectar-seeking insects and is typically more resistant to deer due to its toxicity.
Tropical Milkweed (A. curassavica)
Often found in general nurseries, this milkweed is native to Central and South America and is known for its striking red and orange flowers. While it’s a magnet for butterflies and hummingbirds, it’s important to be cautious with this plant in northern climates.
It can affect monarch butterfly migration and reproduction due to its extended growing season. Research is ongoing to determine its full impact, especially concerning the OE parasite, which can survive on this plant through milder winters.
Ideas For Using Milkweed In The Garden
Using milkweed in your garden can transform it into a vibrant sanctuary. Here’s how you can get creative with it:
- Design a stylized prairie theme by integrating milkweed with tough, sun-loving native plants like goldenrod, Arkansas blue star, prairie dropseed, and black-eyed Susan. This setup is perfect for creating a resilient and picturesque garden scene.
- For areas around ponds or rain gardens, consider planting swamp milkweed. It thrives alongside other moisture-preferential plants, enhancing the lush, water-centric landscapes.
- Add a pop of color with butterfly weed, known for its striking orange blossoms. Pair it with perennials in shades of blue, lavender, or rose, like asters, Joe Pye weed, balloon flower, and meadow sage, to create a stunning visual contrast.
- Milkweed is also a magnet for butterflies. Combine it with other butterfly-attracting perennials to establish a lively and diverse pollinator garden that buzzes with activity.
- Kickstart a native wildflower habitat using seeds. Mix milkweed with various plants that continuously supply pollen and nectar, ensuring your garden remains a haven for pollinators throughout the season.
