Plant Profile: The Versatile Viburnums

Posted on July 18, 2018 by Scott Vogt

In addition to our interest in native trees, shrubs, wildflowers and grasses, one of the goals of the Arboretum is to grow plants which, while not native, are adapted to the rigors of the central Kansas climate. We are especially interested in displaying plants that are not widely grown in the area, but that show excellent hardiness and landscape potential.

The viburnums are a perfect example. While not as widely known as forsythia and lilac, these shrubs deserve much more use in our landscapes. Not only do they offer year-around show of ornamental attributes, such as abundant floral displays, fragrance, outstanding fruiting characteristics, and fall color, they are also hardy and can serve a number of important uses in the landscape.

The Arboretum collection currently features a number of different viburnums, each displaying unique characteristics and qualities. Most of the viburnums can be seen along the east border of the Arboretum, just south of the parking lot. A planting on the north bank of the Amphitheater features several additional kinds along with some newer varieties in the Pinetum.

Fragrant snowball viburnum – Viburnum x carlcephalum https://en.wikipedia.org/wiki/Viburnum_%C3%97_carlcephalum

The three most fragrant viburnums in the Arboretum’s collection are the Koreanspice Viburnum (Viburnum carlesii), fragrant viburnum (V. x carlcephalum), and Judd viburnum (V. x juddii). These three are somewhat similar in appearance because the latter two are hybrids involving a cross between the Koreanspice and another viburnum. They are medium size shrubs (6-10 feet tall). However, our collection also includes a dwarf form of the Koreanspice. All produce clusters of fragrant white flowers in April into May followed by inconspicuous black fruits.

Another fragrant type in the Arboretum is Burkwood Viburnum (Viburnum x burkwoodii). This semi-evergreen grows 8-10 feet fall and produces a white snowball-like flower cluster in April. The fragrance in somewhat sharper, almost spicy.

Like the burkwood viburnum, Willowwood viburnum (Viburnum x rhytidophylloides ‘Willowwood’) is semi-evergreen, retaining its furrowed, leathery leaves throughout much of the winter. This 7-10 foot shrub blooms in April and often to a lesser extent again in October. The blue-black fruits are attractive and can be quite abundant. Another form that is really attractive is ‘Alleghany’ which has tough, leathery leaves, attractive white flowers and abundant bunches of reddish-purple fruit.

Alleghany Viburnum. Photo by Emily Weaver

The Wayfaringtree viburnum (Viburnum lantana) grows as a large shrub or small tree (12-15 feet). While not fragrant to any degree, it produces an outstanding floral display in May, followed by red-black fruit in late summer that persists into fall. Fall color is often red, although it is not consistent.

Another large shrub is the Wentworth cultivar of the American cranberrybush (Viburnum trilobum ‘Wentworth’). The Wentworth viburnum was selected for its large, edible fruits, which progress in color from yellow to red to bright red and persist throughout winter. Birds seek out the fruits from fall through winter. I have often thought that this shrub was at is best on bright winter days with the fruit highlighted against a snowy background. It is also attractive in May with its show of white, flat-topped flower clusters. A dwarf form of the American cranberrybush is found on the north bank of the Amphitheater.

Tucked up under the northeast corner of the Visitor Center is a viburnum that is very attractive. The Doublefile viburnum (Viburnum plicatum forma tomentosa ‘Shasta’) is stunning in bloom as the flowers are held horizontally above the branches. It has insignificant fruit, but the spring flower show makes up for it.

Doublefile viburnum

The last two species in the Arboretum collection are the Blackhaw (Viburnum prunifolium) and southern or rusty blackhaw (V. rufidulum). These two species are native to Kansas and distinct from each other. Blackhaw viburnum is a large shrub or small tree that has smaller leaves and brighter fall color with oranges, yellows and reds. The dense flower clusters develop into purplish-black fruit that the birds love.

Rusty blackhaw is not widely available in the nursery trade at this time, but extremely adaptable and hardy. The glossy dark green leaves turn a nice burgundy-purple in the fall. Large, white, flat-topped clusters of flowers appear in early spring and later produce bunches of fruit that change from red to purple through the fall. Again, many types of birds cherish the nutritious fruit. These two native viburnums are my personal favorite, because they are the most adapted to our Kansas landscapes and have so many wonderful qualities.

Viburnum prunifolium. Photo by Janelle Flory Schrock

Viburnum rufidulum fruit. Photo by Emily Weaver

Any way you look at them, the viburnums are a versatile and highly ornamental group of plants that deserve a greater use in the landscape. We will continue to integrate new species and varieties into our plantings as development of the Arboretum progresses.

What is the Key to Native Plant Happiness?

Posted on April 11, 2018 by Scott Vogt

One of the questions we get every year at the FloraKansas Native Plant Festival, is “why didn’t my ___ come back this year?” It is a great question. Every year at the Arboretum, we ask the same question with some of the plants we establish and want to grow. I wish there was a right answer for every situation and every scenario, but every landscape is unique. Here’s the hard truth that many gardeners don’t often want to hear: the key to native plant happiness lies in identifying this uniqueness and finding the right plants for your plot.

Coneflowers blooming in the lush prairie garden

Match Plants to Your Site

Your landscape is a micro-climate all its own. The soil, sun exposure, orientation to your house, root competition from trees, and many other factors make your garden special. Even your neighbor overwatering their lawn can impact what plants grow best in your scene. There are hundreds of factors that relate to the happiness of your plants and whether or not they will thrive.

The most critical step when establishing your native plant garden is matching the plants with your site. Sometimes I want to try a certain plant in a certain spot that has no business being planted there. I have done it too many times to mention and the result is always the same. I am left holding the hand of a struggling plant that would be much happier someplace else. In the end, I either move it or lose it.

Summer blooms of Kansas gayfeather and gray-headed coneflower

Do Your Homework

If we are honest, I think we have all planted before preparing. The wilting plant in the flower bed is a constant reminder to me that I didn’t do my homework. Look at your landscape. Is it sunny or in the shade? Is the soil clay or sand?

Become familiar with prairie plants that grow in similar situations and evaluate the elements that will impact their survival. Choose plants that will thrive in the micro-climate of your yard. Sun-loving native plants need at least 6 hours of direct sunlight to grow happily. If your flower bed receives less than 6 hours of sun, look at more shade-loving natives.

A thriving landscape begins with matching plants to your one-of-a-kind area. For a lower-maintenance garden, choose plants that occur in the same or similar prairie climates. Anytime you stray too far off, the plants don’t flourish and they require more effort to keep alive. Planting a swamp milkweed on a dry hill or a Missouri evening primrose in a bog will never work.

Butterfly milkweed on a well-drained slope

Learn From Your Mistakes

Good gardeners have lost their share of plants over the years, but what makes them good gardeners is that they learn from their mistakes. With lots of trial and error under their belts, they/we should make better choices…in theory at least.

Other design elements such as succession of bloom, patterns, year round interest, heights, and visual elements become less important when your plant is unhappy in its current location. You must get the right plants in the right place and the other elements will come much easier. A healthy garden begins with a connection to your landscape personally. As you watch and learn what your landscape needs and what it can sustain, you will be able to link the appropriate plants to the location. This important step in the design process allows you to spend more time enjoying and less time “working” in your garden. We all want that from our gardens.

Just one more thing…

Sometimes plants, through no fault of our own, defy all of the above-mentioned rules and simply don’t return. Even in the prairie, plants are ephemeral and rely on self-seeding to continue to grow in an area. As you become more familiar with native plants (and I’m still learning too), you will be able to identify these species. It is their nature to be short lived. True native coneflowers have this characteristic. They are worth planting, but may need to be supplemented with new plants from time to time to keep the area full.

Pale coneflower

Can One Garden Make a Difference?

Posted on March 28, 2018 by Scott Vogt

One of the thoughts that I keep coming back to is this question of whether one garden can make a difference in the world. This question makes me ask even more questions like: Can it slow habitat loss? Will it really attract pollinators? Can a conservation garden be beautiful and functional? Is encouraging biodiversity important? Can such a small garden mimic essential ecological processes? Will these pocket gardens connect people with nature? Even if only some of this is true, then conservation CAN indeed start at home.

Create Prairie Habitat at Home

Creating habitat gardens, prairie gardens, wildflower gardens or whatever we want to call them is now part of the conservation movement. Prairies as we knew them 200 years ago are never coming back to their original form. I would love to see large herds of bison meandering through vast expanses of prairie. We would stand in awe as we looked across the horizon on a rich and diverse landscape that moved with the gentlest breeze. But there remains only a handful of prairies that reflect this bygone era. Certainly, we must protect and try to enlarge these prairie tracts as much as possible, but encouraging the planting of thousands of small prairie gardens is equally important. We must begin at our homes by creating small vignettes that reflect our prairie heritage.

Give Back to Nature

It is through human intervention that these new landscapes can bring about change. Nature now relies on us to help more than ever. Conservation is like paddling upstream on a river. Progress happens as long as we keep paddling, but as soon as we stop the river pushes us backward. Incremental change or success is a result of our concerted efforts focused on moving us upstream. We can give nature back as much as it gives us. We rely on each other and we can no longer be separated from one another.

So to answer my question: Yes. Every garden is important in so many ways. To choose to restore, create or protect a habitat makes a difference. Each landscape/garden, no matter how small, can truly have a positive impact on the health of the environment. Imagine your garden habitat connected with hundreds of other prairie landscapes throughout each community, as shown through the Million Pollinator Garden Challenge. Pollinators and wildlife will benefit and we will feel good about the role we play as we care for nature.

Here are a few ways that incremental change can happen:

Reduce the use of chemical fertilizers, herbicides, and pesticides.
Use native plants as much as possible, because wildlife prefers these plants.
Plant trees and shrubs that develop fruit and berries that birds need as they migrate or overwinter.
Design a garden that has a variety of plants blooming throughout the year.
Incorporate plants that adapt to your site, which makes them low maintenance.
Transition parts of your lawn to wildlife habitat.

Instead of looking at all the negative that surrounds us daily, let’s focus on the positive role we can have in our neighborhoods. It is easy to be all doom and gloom, but really we should continue to paddle forward. I believe small, steady changes provide us with a unique opportunity to discover what it means to be a steward of creation. Who knows? Maybe your garden will be an inspiration that others use to begin their own journey. One garden can make a tremendous difference.

If you live in Kansas and don’t know where to start in establishing a prairie habitat garden, we invite you to further explore our Prairie Notes blog and attend our upcoming FloraKansas Native Plant Festival.

Plant Profile: Wild Senna, Senna marilandica

Posted on August 16, 2017 by Scott Vogt

Sometimes there are plants that surprise you. It’s not that they are doing anything new, but for some reason you notice them in ways you hadn’t before. This summer, for me that plant is wild senna. I have been gawking at it over the past few weeks and admiring its tropical look.

Our one wild senna plant has been putting on quite a show in the shade garden this summer. The bright yellow flower clusters are stunning. The fact that I missed them in past years makes me think that I am not very observant. These showy blooms are held atop the feathery, deep green, locust-like leaves. The horizontal leaves help the flowers stand out even more.

After the blooms are spent, long narrow pods begin to develop and droop from the stems. As the pods mature, small beans are held tightly inside. Over time, the pods turn from green to brown and crack open, releasing the seeds. These seeds are relished by many types of birds, including quail and dove.

Wild senna can grow up to six feet tall, but is typically only three to four feet. Plants have a loose, open, shrubby habit with several stems growing from a central point. It makes a fantastic accent plant or backdrop for shorter perennials in your native plant gardens.

Here at the Arboretum, it is happy in a spot that gets only partial sun. In the wild, it grows in open woods and prairies with medium to wet soils. It is a pretty plant that should be used more in the landscape.

One of its most important functions in the landscape is hosting a variety of pollinators. It is the host plant for Cloudless Sulphur, Orange-Barred Sulphur, Tailed Orange, Little Yellow, and Sleepy Orange Butterflies. Many different types of bees love the flowers, too.

This season’s display by just one wild senna plant has made me realize we should be using it more in our gardens. It is a great trouble-free choice as a taller accent plant, a native wildflower for your woodland edge or for a more formal cottage garden. It is a pretty plant that pollinators need.

Six Native Groundcovers That Thrive in the Sun

Posted on March 1, 2017 by Scott Vogt

As you think about your native landscape, taller plants are easier to plug into the design. There are more choices from which you can add diversity, color, texture and habitat. These taller layers are the backbone of any plan, while the edges or ground level are often overlooked. In my opinion, the border plants are just as important because they define the edges. The larger perennials typically overshadow these native groundcovers, but here are a few that stand out in the landscape.

Missouri Evening Primrose-Oenothera macrocarpa

In the wild, this low growing wildflower is found clinging to exposed hillsides. If it can survive that environment, it will be a tough drought-tolerant plant for any sunny spot. The large, showy, yellow flowers bloom from May through August, but the majority of the blooms come in April and May. One plant can spread up to 24 inches while only reaching 6 to 12 inches tall. Obviously, it likes it dry, so don’t over water them. They look great along walkways or spilling over rock walls with their silver green leaves and reddish stems.

Purple Poppy Mallow-Callirhoe involucrata

Some like it hot, but these like it really hot. The deep tap root of Purple Poppy Mallow sustains it during times of drought. These roots are starchy and supposedly taste like a sweet potato. (I don’t know if I am that hungry, but it may be worth a try.) The magenta cup-like blooms appear throughout spring and into summer. I like to interplant with low grasses or shorter perennials that bloom later in the season, such as blazing stars or goldenrods. The stems hug the ground and ultimately spread 24-36 inches wide and 6-12 inches tall.

Blue Grama ‘Blonde Ambition’-Bouteloua gracilis

Unlike any other native grass, ‘Blonde Ambition’ will make an impact in your garden. The eyelash-like seedheads dance with even the gentlest breeze atop the fine blue-green foliage from mid-summer into winter. Selected for its unique habit and hardiness, it can be used in a variety of settings from clay to sandy soils. It gets larger than most Blue Grama grass, maxing out at 24 inches. Space them 18 to 24 inches apart for best display. Regularly, Blue Grama is found growing with Buffalograss in the shortgrass prairie, making it an important native grass of the Great Plains.

Rose Verbena-Glandularia canadensis

This plant holds the record for most months in bloom. I have seen it in bloom from March through December. It is one of the first to bloom in the spring and if we get some beneficial rain in the fall, it will bloom again. In the prairie, rose verbena can be found in open bluffs and rocky outcroppings. It requires minimal rain and terrible soil for the best growth. Sounds like a winner to me. The vibrant pinkish-purple blooms will brighten any border. Give it room to spread. One drawback is that they are not very long lived, every few years, plants will completely die out or move. I think that they bloom themselves to death. Just replace with new plants and again enjoy this sun loving groundcover.

Rose Verbena-Photo courtesy of Craig Freeman

Stiff Coreopsis-Coreopsis palmata

Each spring, the golden yellow blooms of this prairie beauty burst open with an eruption of glorious sunshine. The stems are lined with leaves that resemble little hands lifted skyward. It is a favorite of pollinators as they flock to the nectar rich flowers from late spring to early summer. I give it some room to roam since it slowly spreads to fill in an area when it is happy. Eventually, spreading to 36 inches or more and growing 24 inches tall, this wildflower is a great alternative to its other coreopsis cousins.

Coreopsis palmata-By Frank Mayfield (Flickr: Coreopsis palmata PRAIRIE COREOPSIS) [CC BY-SA 2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons

Prairie Dropseed-Sporobolus heterolepis

At one time, this was one of the top selling grasses nationwide. It is a favorite of mine because it is long-lived and tough. It is so tough they are planted in mass in street medians. The fine textured leaves and airy, fragrant panicles are a nice addition to any landscape. Each clump can reach 12-18 inches wide and up to 24 inches tall. The entire plant turns shades of orange and yellow in the fall providing multiple seasons of interest. It is great in a border, as a groundcover, in an informal prairie setting or as an accent to other short or mid-range perennials.

Sporobolus heterolepis-By Krzysztof Ziarnek, Kenraiz (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons

How Do You Learn About Native Plants?

Posted on March 30, 2016 by Scott Vogt

This weekend, I did some reflecting on the past 19 years I have spent at the arboretum. I thought I knew so much when I was hired as the horticulturist. After all, I had just graduated from Kansas State University with a horticulture degree. There wasn’t anything I didn’t know. But after the first week, I was in over my head.

It was July in Kansas. Need I say more?

One of the first things I quickly realized was that I knew virtually nothing about native plants. I had learned about a few native trees and shrubs in my college classes, but I couldn’t identify more than five wildflowers. My learning curve was steep those first few years. I was going to sink or swim at this new job by how much I knew about native plants. So I set out to learn all I could about the plants that grow on the prairie.

Bison-Photo by Craig Freeman

7mS4mWofHolcomb_FinneyCoKS_CFreeman_01Jul1995

Finney County KS-Photo by Craig Freeman

The most formative experiences that I had were the many seed collecting field trips we made throughout the state. It was so enlightening to see the plants growing in their natural environment. Those memories guide how I design gardens today. I became familiar with the plants, but more importantly I learned where they like to grow and who they like to grow with. Just like us, plants need to be in communities that are vibrant, healthy and sustaining. Native plants rely on each other. High quality prairies and even gardens have communities of plants that live harmoniously together.

RusselSprings_LoganCoKS_CFreeman_19May1999

Logan County, KS-Photo by Craig Freeman

Chalk Formations-Photo by Craig Freeman

Collecting seeds forced me to learn the scientific names of the plants. Each seed had a specific set of conditions that it must be subjected to in order for germination to occur. This too was a fascinating process that required me to learn. It was extremely rewarding to take some seed from the wild and get it to germinate in the greenhouse and ultimately place a new plant for the seed we collected into the arboretum for others to enjoy.

CimarronNatlGrassland_CFreeman_26Jun1988

Cimarron National Grassland-Photo by Craig Freeman

RocktownNaturalArea_RusselCoKS_CFreeman_08Oct1988

Rocktown Natural Area-Russel County-Photo by Craig Freeman

I read catalogs and books about native plants. I grew, planted and killed several native plants in an attempt to continue that learning process. I moved plants that were not happy to other areas in the garden where they began to thrive. These exploratory trips – we called it “55 mph botany” – helped me hone my identification skills as we traveled many of the back roads of Kansas in search of unique native plants. Each of these experiences influence plant choices, mixtures and sequences in landscape plans. As native plants have become more mainstream, more information is available. Naturally, I am still learning.

Flint Hills-Photo by Craig Freeman

I say all this to encourage gardeners, specifically native plant enthusiasts, to learn everything you can about at least 25 plants that will grow well in your landscape. From those, there is nearly an infinite number of plant combinations. By matching plants to your sight, the guess-work has been taken out of the equation. This will increase your successes and diminish your failures. If the plants are happy, they will take care of themselves. And that will increase your enjoyment while greatly reducing your upkeep and maintenance.

Challenge: Start with learning about 10 native plants, eight wildflowers and two grasses. As you learn about these plants and incorporate them into your garden where they like to grow, I believe you will be rewarded in time with a landscape that works for you, not against you. You will have a community of plants that flourish together.

Let the learning begin!

Silphiums: Four Pillars in the Tallgrass Prairie

Posted on August 19, 2015 by Scott Vogt

2015 seems to be the year of the genus Silphium in the arboretum. In recent years, I can’t remember them looking so bright or growing so tall. With the spring and summer rains these sun-loving, yellow-flowered plants have reached a new level. In fact, they are among the tallest plants of the prairie in late summer and autumn. We grow and sell four species: Prairie Dock, Silphium terebinthinaceum; Cup Plant, Silphium perfoliatum, Compass Plant, Silphium laciniatum; and Rosinweed, Silphium integrifolium. Each of these are distinct and easily identified by their unique leaves.

Prairie Dock (Silphium terebinthinaceum)

I call this the Hosta of the prairie. It almost has a tropical-look to it, with large rough leaves up to one foot wide and two foot long. It will make a statement in the landscape, but give it plenty of room and keep it away from walkways, because the long stems tend to arch over the path. Individual clumps can become large over time reaching six feet in diameter. The yellow flowers develop in mid-August atop tall leafless stalks. This member of the tallgrass prairie is one of my favorite wildflowers. In my opinion, Prairie Dock is a must in your wildflower garden. Update (2023), I love this plant but we have found that it self seeds everywhere. If you include it in your garden be prepared to deadhead after flowering to avoid a monoculture of prairie dock. Use with caution.

Prairie Dock

Prairie Dock with Missouri Black-eyed Susan

Cup Plant (Silphium perfoliatum)

A natural bird bath in the landscape. Each pair of leaves clasps around the stem forming a small basin. When it rains, these crude cups fill with water that is then available to wildlife. They stand tall in the landscape and therefore work well as a screen. I have also used them as a dark green background for other shorter perennials like black-eyed Susan, and gayfeather. The yellow blossoms can be seen starting in July and are visited by a host of butterflies. Later, birds cherish the seeds. Cup Plant thrives in heavier clay soils or even wet conditions. It will be happy in any setting if given ample sunlight.

Cup Plant with water

Cup Plant Flower

Compass Plant (Silphium laciniatum)

Do you need directions? This is the plant that can help. The interesting basal leaves look like flat hands. Those lower leaves usually orient themselves north-south to minimize exposure to the intense summer sun, hence the descriptive common name. These extremely tall (up to ten feet) wildflowers are found in prairies and glades throughout the eastern third of Kansas. Each stem is covered with tiny white hairs that give it a rough, bristly feel. The bright yellow flowers emerge along the upper parts of the plant in summer. Split or broken stems exude a clear sticky resin much like pine sap. Native Americans used this resin as a mouth-cleansing chewing gum. I think I will stick with Trident®.

Dyck Arboretum Blog: Silphiums, Compass Plant

Compass Plant Leaf

Rosinweed (Silphium integrifolium)

Rosinweed is shorter, but just as tough as the other Silphiums. Again, the name describes the resin exuded if the stem is bruised or broken. The golden yellow flowers that mature at the top of the stems are beautiful in the summer. It is a pollinator magnet, attracting bees, butterflies and even hummingbirds to the flowers. It becomes a natural bird feeder in the fall and winter as the seeds are devoured by birds. It is quite drought tolerant once established and is at home in a wide variety of soils.

Rosinweed

While each of these wildflowers are unique in appearance, especially as you look at the leaves, they all have that “clear, sticky juice” that exudes if the stem is damaged. I love them in the landscape, but they need room because they grow so tall. They are great in prairie settings or areas on the periphery of your yard. You can’t go wrong – just give them plenty of sunlight so the sunflower-like blooms can brighten your summer landscape.

Each of these plants can be purchased at our FloraKansas Fall Plant Sale, September 11 to 13.