How To Build The Perfect Monarch Butterfly Garden

monarch on pink flowers

Daniel Potter freely admits he’s not an expert on monarchs. But as a professor of Entomology at the University of Kentucky, he and his grad students sure love to run experiments. Recently, they completed a 2-year study on the likes and dislikes of the popular orange and black butterfly. Now for the first time ever, there’s a roadmap for building the perfect monarch garden.

WHY WE CARE

If you’re reading this post, you’re probably already a monarch fan. The butterflies’ annual migration from Mexico to Canada is one of the most spectacular events worldwide. All told, the tiny insects fly upwards of 2000 miles roundtrip each spring, stopping four times along the way to breed and lay their eggs. They are the only butterfly species to make such a long, two-way migration.

monarch migration

The past 25 years, however, have seen a sharp decline in monarch populations. Part of this is due to loss of habitat at the butterflies’ overwintering site in Mexico. Activities such as logging, agriculture and urbanization have all taken their toll on the central highland forests that play host to the insects six months out of every year.

But by far the most significant factor driving the decline is the dwindling supply of a plant called milkweed. The native wildflower is the only plant that monarch caterpillars will feed on. And without it, the butterflies cannot complete their life cycle, sustain their migration and ultimately, perpetuate their species.

monarch feeding on milkweed

MONARCH BUTTERFLY GARDENS NEED MILKWEED 

According to the North American Monarch Conservation Plan, we need 1.8 billion milkweed stems to replace those that have been lost to agriculture and urbanization. And these contributions need to come from all land sectors in order to sustain the annual migration. This includes farms, roadsides, schools, zoos, rights of way and yes, suburban and urban gardens located along the butterflies’ migratory corridor.

Luckily, an initiative called the Monarch Waystation Program is starting to make a crucial difference. Established in 2005, it engages citizens in conservation by providing instruction and materials on how to create habitats for monarchs. The guidelines are simple – Plant two or more milkweed species for the caterpillars, some nectar sources for the adults and you become part of a national registry. To date, over 6000 Monarch Waystations in 46 states have become part of the effort. 

WHAT MONARCHS LIKE

And as it turns out, the Waystation Program Registry provided the perfect jumping off point for Potter’s research into monarch butterfly gardens. A quick Google Earth search revealed hundreds of habitats dotted along the butterflies’ northward route. Furthermore, they represented every kind of landscape.

As Potter put it, ‘Some were non-structured, others ‘wild’, and still others were surrounded by hardscape or located in open rural areas.’ Below are some aerial shots of a few of them. (Photo courtesy Dr. Daniel Potter.)

What Potter and his team wondered was this – with all of this diversity, could there be certain habitats that appealed to monarchs more than others? The group decided to survey 22 citizen-planted Waystations in an effort to find out. Their research ended up producing some interesting results. 

1. MONARCHS LIKE STRUCTURE

Like most species, monarchs use visual cues to zero in on what they’re looking for. And in the butterflies’ case, these ‘search images’ are made up exclusively of milkweed. But as the Registry revealed, not all waystations were the same. Did monarchs favor some monarch butterfly gardens over others?

Monarchs from ‘search images’ for milkweed

To find out, the researchers counted larvae and caterpillars for a year in their target Waystations to see if the type of habitat made any measurable difference.

monarch caterpillar on milkweed leaf

Monarch caterpillar on milkweed leaf

And they discovered that yes, the butterflies had a strong preference. A structured garden, with milkweed set off by mulch, attracted three to five times more monarchs.

The takeaway? If you want more monarchs, make it easy for them to find the milkweed to lay their eggs on. Plant it apart from other plants. Even better, surround it with a mulch circle. But make sure to provide other nectar producing plants nearby for the returning adult butterflies to feed on.

2. MONARCHS PREFER A NORTH-SOUTH ACCESS

Interestingly, the researchers found that gardens with unimpeded north-south access recruited more monarchs. This makes sense since it coincides with the butterflies’ migratory route.

monarch migration map

Monarchs prefer gardens with a north-south access

3. THE TALLER THE BETTER

While all milkweed species are suitable for food, not all are equally favored by monarchs. To find the answer why, the group compared 8 species of milkweed all grown in Kentucky and native to the area. They evaluated them as to their suitability for egg-laying as well as their usability as food for monarch caterpillars. And there was a clear preference.

Where they had a choice, monarchs preferred the taller varieties, Swamp, Common and Showy over the smaller varieties like Butterfly weed

The takeaway? If you want to attract more egg-laying monarchs to your monarch butterfly garden, plant the tall, broadleaf milkweed species like common, swamp or showy milkweed.

4. MILKWEED CULTIVARS ARE EQUALLY TASTY

But what about all of the new milkweed cultivars, you ask? As it has grown in popularity (mainly due to monarchs), milkweed now has many cultivars boasting unusual colors and sizes.

Asclepias Gay Butterflies Mix/White Flower Farm

Not to worry. Potter and his students discovered that monarchs find these cultivars just as attractive as the straight species. But again, go with the bigger varieties if you want more monarchs.

5. DON’T LET YOUR MONARCH BUTTERFLY GARDEN BECOME AN ECOLOGICAL TRAP

Finally, there’s the case of tropical milkweed, a non-native plant that has exploded in popularity over the past decade. Both gardeners and monarchs love it. But buyer beware. Tropical milkweed is not ‘bad’, per se, but when planted in warm areas of the U.S. it encourages monarchs to stick around longer and even enables them to winter-breed.

tropical milkweed

Tropical milkweed, Asclepias curassavica

Research shows, however, that monarchs breeding on tropical milkweed throughout the winter (rather than returning to Mexico) have higher levels of protozoan infection compared to monarchs in the normal migratory cycles. It turns out that migration is key to outrunning these pathogens.

The takeaway? Stick to the tried and true native milkweed species in your monarch butterfly garden and help the insects keep to their schedule.

To learn more about Daniel Potter and his research into monarchs and other insects, click here for the Dr. Daniel A. Potter Laboratory.

 

Flowering Kale: The Coolest Cool-Season Ornamental

The distinctive rosette of ornamental kale

Long before it became a trending food, flowering kale was a garden star, delivering a pop of color to fall’s graying landscape. The plant is not only prized for its striking foliage and rosette but is also one of just a few species that thrives in cold weather. Indeed, flowering kale likes cold temperatures so much that it often stays attractive well into winter. I can’t think of a better choice for fall gardens and containers.

IS IT CABBAGE OR KALE?

Things can get confusing at the nursery. Even though they belong to the same family, cabbage and kale are actually not the same. Cabbage is a multi-layered vegetable whose leaves come together to form a head.

Cabbage head growing in the garden

Conversely, kale has a cluster of upright, open leaves called a rosette.

The bright pink rosette of flowering kale.

Ornamental kale

That being said, you will generally find varieties with broad, flat leaves labeled as ‘ornamental cabbage’ and those with ruffled, crinkled or curled leaves labeled as ‘ornamental kale’ at the store. 

BORN TO BE BEAUTIFUL

Selectively bred to produce spectacular leaves and rosettes, flowering kale comes in all shapes and sizes. The outer leaves are typically blue-green in tone while the rosettes start out pale green, then gradually shift to pink, red, purple, or cream depending on variety. The florets expand as temperatures cool, .

The distinctive, blue-green outer leaves of ornamental kale

In recent years, innovations in color and form have made ornamental kale a ‘must-have’ in fall gardens. The new hues work beautifully with chrysanthemums, pot marigolds and pansies. And the variety in sizes makes the plant suited to just about every container.

Magenta-toned flowering kale with ruffled edges.

Flowering kale rosette featuring ruffled edges

Best of all, flowering kale usually reaches its crescendo just after the first frost. And some plants maintain their intensity all the way until spring.

flowering kale covered with snow

IS KALE A PERENNIAL?

Kale is a biennial, which means it has a two-year life cycle. The first year it produces leaves and the second year it produces flowers. Most people grow it for its ornamental qualities, however, and throw it out after the first year.

FLOWERING KALE CARE

Ornamental kale and cabbage require very little maintenance and are bothered by few pests. They prefer moist, well-drained soil and benefit from feeding. For the best color, position your plants in full sun.

Since there won’t be much top growth after September, look for plants in one-gallon size pots. Then keep spacing tight (10 to 12 inches) to encourage the rosettes to remain small. Over time, they’ll attain a width of approximately 12 inches.

Small garden with geometric display of yellow and pink flowering kale.

THE MOST POPULAR VARIETIES

Ready to get started? Here are some of the most popular varieties:

REDBOR

Redbor has narrow, upright deep purple, ruffled leaves. It is the tallest kale grown and can reach a height of 3 feet. Use it by itself in a parterre garden, or try massing it behind annuals like chrysanthemums, pansies and violas in contrasting colors.

Redbor kale

Purple-leaved Redbor kale

PEACOCK SERIES

Peacock series ornamental kale are large, open and frilly plants that can reach 2 feet across. They feature deeply serrated, feather-like leaves and cream or red-toned centers. Extremely cold hardy, they can survive even the harshest of winters.

Peacock series ornamental kale

Deeply serrated, feather-like leaves distinguish Peacock kale

PIGEON SERIES

Pigeon Series (Pigeon Pink and Pigeon Red Pigeon Purple and Pigeon White) ornamental kale most closely resembles cabbage with its tight rosettes of light pink, dark red or creamy white. The round-shaped plants have wavy outer leaves that remain medium to dark green while the flower-like centers change color. I’ll often combine different colors to form geometric patterns.

Pigeon series flowering kale

The tight rosettes of ornamental kale ‘Pigeon Series’

OSAKA

Osaka Pink, Osaka White and Osaka Red are often termed ornamental cabbage due to their smooth, flat leaves and tightly-packed rosettes. The plants produce layers of wavy edged green leaves while the florets gradually change to bright purple, pink or cream.

Osaka series flowering kale

Osaka series ornamental kale has flat green leaves like cabbage

IDEAS FOR DESIGNING WITH FLOWERING KALE

Flowering kale’s wide range of sizes make it equally attractive mixed with other flowers or all on its own in a garden or container. Below is a parterre garden I created using two broad-leaved varieties. 

Parterre garden with geometric arrangement of white and purple flowering kale.

Parterre with two different varieties of ornamental kale/herebydesign.net

The tall, frilly purple and green varieties and the broadleaf Osaka make a contrasting statement in large containers. In this planter box, the trailing ends of bright green lysimachia soften the mix.

The Impatient Gardener/Pinterest

In this small container, I’ve combined ornamental ‘cabbage’ with violas and Swedish ivy. The greenish-purple kale complements the colors of the dusty red pot.

Fall container with pansies, Swedish ivy and flowering kale.

Fall container with ornamental kale/herebydesign

In this formal urn, I played up the drama using tall grasses as a centerpiece. Then I added different varieties of red and green flowering kale, purple violas and mahogany-toned potato vine to create a warm-toned composition. 

Fall container with purple fountain grass, mahogany sweet potato vine and frilly green flowering kale.

Fall container with grasses, flowering kale and potato vine/herebydesign

Since ornamental kale retains its color well into winter, it also pairs beautifully with evergreen branches, pinecones and catkins to form stunning holiday arrangements.

Photo Credit/Canadian Gardening Magazine

In this fall garden, the deep purple Redbor pairs beautifully with salmon chrysanthemums and straw-colored grasses. The maiden grasses’s creamy plumes add a delicate touch.

Photo Credit/The Hoosier Gardener

Finally, when combining flowering kales with other plants, think about varying the foliage. Here, purple fountain grass and lime green potato vine provide color. And the frilly purple variety lends contrast. 

Photo Credit/Three Dogs In A Garden

Ready to get started? Check out your local nursery for the newest ornamental kale varieties. And don’t be afraid to combine them with other cool-season companions like evergreen branches, dried flower heads, catkins and berries. These fillers will add interest to your containers and keep the show going well into fall.

 

Lespedeza: The Best Fall-Flowering Shrub You’ve Never Heard Of

lespedeza thunbergii

Lespedeza thunbergii

Lespedeza. Judging by the sound of it, you’d think it was an island off the coast of Italy. And the plant that bears its name certainly looks Mediterranean. Yet, I had never heard of this magnificent, fall-blooming shrub until a client of mine showed me a pair in her garden. Here’s why I’ve been a fan ever since.

SOME BLACK SHEEP IN THE FAMILY

It turns out that while I may have been uninformed, the genus lespedeza has quite a reputation. A member of the pea family, it comprises over 40 flowering plant species. These include shrubs and trailing vines, some of which are grown as ornamental plants and others for forage or to prevent erosion. But some species exhibit some downright deviant behavior.

Take for example Lespedeza striata, commonly known as Japanese clover. A ground-hugging annual, it forms dinner-plate size patches of dark green leaves with wiry stems. In late summer it produces a mass of tiny pink flowers. The downside is it also delights in choking out turf.

lespedeza striata

Lespedeza striata, commonly known as Japanese clover

Then there’s Lespedeza cuneata, an extremely aggressive warm-season perennial. Also known as Chinese bush clover, it was brought to the United States from Asia in the late 1800s to prevent erosion. However, it rapidly began invading open spaces, out-competing native vegetation. Now the upright, gray-green shrub with cream flowers is classified as an invasive weed in the Midwest and eastern United States.

lespedeza cuneata

LESPEDEZA THUNBERGII, THE STAR OF THE GENUS

But, there is a member of the family who is considered the star of the genus. Relatively unknown to the home garden, it is the species Lespedeza thunbergii (also known as bush clover.) Recipient of the Royal Horticultural Society’s (RHS) Award of Garden Merit, it boasts beautiful blue-green foliage, cascading panicles of rosy-pink flowers and a dramatic fountain-like appearance. 

Moreover, unlike other family members, bush clover sticks to its place. Slowly developing over the summer into a roughly 6-foot mound, this beautiful shrub spends August and September laden with thousands of tiny pink flowers. It’s a burst of color just when you least expect it, and at a time when most other perennials are losing their luster.

DESIGNING WITH LESPEDEZA

Designing with Lespedeza thunbergii offers many opportunities. Given its large size, the shrub is a natural for the back of the border (or used as a specimen.) Although it will tolerate some shade, it flowers best in full sun, where is combines beautifully with other fall-blooming perennials like caryopteris, Russian sage, asters and chrysanthemums.

At my client’s home, we’ve gone for a spring-like approach, pairing her shrubs with ‘Little Lime’ hydrangeas, apricot shrub roses, Icy Pink vinca and the upright swords of bearded iris. Anthony Waterer spirea, Longwood Blue caryopteris and white Japanese anemones provide subtle background color.

september perennial border in virginia

To date, the only other place I’ve found Lespedeza thunbergii is at Maryland’s Brookside Gardens, where last fall, I spied it displayed in one of their formal gardens. Here, their staff paired it with Autumn Joy sedum, giant hyssop, maiden grass, pink anemones and purple top vervain to form a stunning combination.

brookside gardens

Brookside Garden’s fall display 

MAINTAINING LESPEDEZA

Bush clover flowers on new wood, so you can prune it anytime without shaving off next season’s blooms. Most people cut stems to the ground in late winter. It’s astonishing to watch the shrub bounce back over the summer months into a large, bluish-green sphere as big as most men.

Deer resistant and virtually pest and disease-free, bush clover grows in zones 4-8. The roots are winter hardy to USDA zone 6, but expect the top growth to die back during the winter. (For more about the USDA Plant Hardiness Map and how to use it, click here.)

LESPEDEZA OWES ITS NAME TO A TYPO 

Lespedeza owes its name to Vicente Manuel de Céspedes who served as governor of the Spanish province of East Florida from 1784-1790. Céspedes gave botanist André Michaux permission to explore East Florida in search of new species.

Michaux ended up discovering the flowering species, which he named in honor of the governor. Unfortunately, when he published his book in 1802, the name de Céspedes was misspelled as de lespedez. The current botanical name lespedeza allegedly derives from this mistake.

 

The Late-Summer Delights Of Sedum ‘Autumn Joy’

sedum autumn joy in the garden

Are you on the hunt for a dependable plant for your late-summer garden? Look no further than sedum ‘Autumn Joy.’ Come August, its lovely clusters of tiny flowers are just starting to adopt a rosy-pink hue. And best of all, the blooms keep going for weeks, gradually turning a dusty red that’s the perfect compliment to fall. Continue reading

Chesapeake Bay Wildflowers: July’s Top 10 Bloomers

IMG_0118

‘There are always flowers for those who want to see them’ – Henri Matisse

For most of my life, I’ve been more attracted to ornamentals than to wildflowers. Even though I’ve noticed many beautiful species in the landscape, I’ve never really taken the time to observe them. You might say, I’ve been wildflower blind. Continue reading

How To Cope With Boxwood Blight: An Expert Weighs In

It’s not every day you get to discuss your problems with an international expert. But Lynn Batdorf is the real deal. Batdorf is the world’s top resource on everything boxwood, including all of the diseases and pests that affect this diverse species. Recently he spoke to me about how to deal with the latest threat to our gardens, the dreaded boxwood blight. Continue reading

Why Star Magnolia Deserves A Spot In Your Garden

Magnolia stellata, commonly known as Star Magnolia

First introduced from Japan in the 1860s, star magnolia has long been a resident of the American garden. One of the smallest magnolias, it produces a cloud of showy white or pink flowers in early spring. The blossoms appear before the leaves, dangling like fallen stars on the tree’s smooth, bare branches. It’s enough to leave you speechless. Continue reading

The Best Hellebore Varieties For Your Winter/Spring Garden

February can be a bleak time on the East Coast. Days are short and the sky hangs low on the horizon. But there’s a small-sized perennial whose early, colorful blooms never fail to lift my mood. It’s the lovely, cup-shaped flower called hellebore, commonly known as the Lenten Rose. Continue reading

Change Up Your Menu With These Six Exotic Fruits

Lots of exotic fruits have been turning up in American produce aisles lately. Colorful and peculiar, they have odd shapes, strange features like fuzzy hair and curious tastes like cucumber melon. Continue reading

Clear the Air With These 10 No-Fuss Houseplants

Peace lilies can help clear the air of harmful toxins

According to the Environmental Protection Agency (EPA), Americans on average spend 90 percent of their time indoors. And indoor environments can be poor, trapping dangerous chemical toxins as well as bacteria, pollens and mold. Continue reading