Stumped: Reimagining a garden after tree loss

Ten years ago, my spouse and I purchased our first home in Central Kansas. The backyard was dominated by a large American Elm tree that had miraculously, and with a lot of help from a local arborist, survived the bout of Dutch Elm Disease that had taken nearly all of the American Elms in town in the 1990s.

In June of 2013, an aged American Elm tree beautifully shaded our backyard.

What this meant was that, like many Kansas homeowners, we had a large area of dry shade to contend with. Informed by my spouse’s childhood experiences growing up in the bush of South Sudan, we were not inclined to water our lawn just to maintain the status quo. So, the challenge was, how do we increase biodiversity in this backyard without using supplemental watering? We were stumped.

We tried a few things in the deep shade of the tree – transplanted spiderwort, river oats and columbine from a friend. And although these species hung in there pretty well, they certainly did not thrive. Ideally, they would have liked a little more sun and a lot more rain.

Here at the Arboretum, in our list of frequently asked questions at FloraKansas Native Plant Days events, “Which Kansas native plants will grow well in dry shade?” rises to the top. Unfortunately, the answer is “Hardly any.”

In a prairie ecosystem, trees will only flourish along creekbanks or near another water source. The garden condition “dry shade” is a human-created environment that simply does not exist in nature. For humans, and particularly for those of us who are relatively new to gardening with native plants, this is often a difficult reality to process and to accept.

Over the years, several major ice storms and wind events have weakened the structure of the tree. The final blow came in August of 2021. It was time to have the tree removed.

Another reality that was difficult for us to accept was that the elm tree was in an irreversible decline. The health of the tree had been compromised by an ice storm in 2007. Slowly over time, the rotting that had begun after that first injury made the elm more susceptible to being damaged again. As it became clear to us that this tree was in a death process, we focused our efforts on developing the front yard and enjoyed the shade while we could.

After the tree had been removed, we needed to reimagine what our backyard was going to be.

In the fall of 2021, we finally admitted to ourselves that the tree needed to be removed. We allowed ourselves a year to sit with the new reality of a full sun back yard. We left the stump and planted it with yarrow, little bluestem and soapwort. We have also contemplated growing mushrooms in the stump. Over time, we will watch the stump disintegrate and return to the earth. For now, it provides a lovely focal point.

In the raised rock garden beds surrounding the stump and along the south fence, we have filled in with plants that prefer well-drained soil, including butterfly milkweed, Missouri evening primrose, blue flax, soapwort, and several adaptable creeping groundcovers. Also, I couldn’t help but try my guilty pleasure plant that would prefer to be at higher elevations, pineleaf penstemon.

In a test area that was formerly in deep shade, we have seeded buffalograss and encouraged it to spread. In retrospect, I wish we had done this to the whole lawn area right away, because this spring, much of the former fescue lawn has mostly been populated by dandelions, wild lettuce, henbit, clover and spurge. Nevertheless, we are motivated to continue to populate the back yard with sun loving prairie plants.

The lawn is currently a polyculture of warm season grasses and annual weeds (please don’t judge!), but we are on our way to establishing buffalograss and determining where we would like to plant native perennials.

I know there are likely many things we could have done so much better. Do I have regrets? Definitely. Could we have saved that elm tree by trimming it every year? Probably. In stewarding this small piece of the land, we are far from perfect. But honestly, in this process, I’ve learned that the land is more forgiving than humans are, as long as you don’t try to bend it to your own will. If you listen and observe your garden, over time, it will tell you how it wants to be. It will allow you to make mistakes, and then correct them. It will teach you to view the cycle of life in new ways. And if you can hold back from trying to control it too much, you will be rewarded by new and unexpected discoveries on a daily basis.

Tree loss at the Arboretum

One of the hardships of being a gardener is the loss of a long established tree. It is no different here at the Arboretum. We have lost a few trees that were planted at the founding of the Arboretum. The loss of these large specimen trees leave a huge hole in the landscape that will take another few decades to fill.

Austrian Pines

We continue to lose a few pine trees each year. All of our Scotch pines are gone due to pine wilt. We are now losing larger ponderosa and Austrian pines. We have a tree that is over 40 years old that was green last fall but is now totally brown, dead in less than six months. This could be due to a number of factors such as drought (although we watered it last summer into the fall), or some sort of tip blight. We believe this browning is blight. We are removing these trees as they die, which is heartbreaking.

Austrian Pine turning brown from the bottom to the top

Southwestern White Pine

This was one of the evergreen trees I recommended to plant a few years ago. It is no longer a viable alternative to some of the other two and three needle pines that have been lost to disease. We have lost a row of these due to pine wilt. Pine wilt causes a rapid decline of a pine tree in just a few months. The infected trees must be removed and burned to stop the spread.

River birch

In our parking lot median, we have slowly been losing an original row of river birch. Admittedly, this was not the ideal location for river birch. We were watering these trees almost weekly in the summer since they are not very drought tolerant and have shallow roots, which leaves them stressed in the heat sink of the parking lot. I see this same river birch scenario in other landscapes with river birch planted front yards and drier areas. Often times, these trees are struggling just as ours were unless they are receiving frequent irrigation through the summer. As their name implies, they grow best in wetter areas along streams, swales and ponds. We are replacing our river birch with a variety of deeper rooted trees such as oaks.

River Birch in parking lot median

Autumn Purple Ash

What a big surprise this spring when this large white ash didn’t leaf out. One side has leaves, but the other side is completely bare. It has been infested with borers with have damaged the trunk, branches and stems. It showed no signs of disease last year. Even if I had seen and diagnosed the problem last fall, the treatment would not have been very effective. The result would have been the same. We are holding out hope that it will miraculously leaf out yet this spring. If not, it will need to be removed.

Autumn purple ash struggling to leaf out

Pin Oak

It is well known that pin oaks suffer from iron chlorosis, which causes a yellowing of the leaves. Chlorosis in pin oaks is usually due to a deficiency of iron in the leaves. Iron is important for chlorophyll synthesis in plants, so when it is deficient, leaves cannot make chlorophyll, resulting in a yellow appearance. Chlorosis of pin oaks is typically associated with alkaline soil pH – pH greater than 7, which is common in our area. This iron deficiency eventually weakens the tree and stunts its growth. Trees can be treated by injecting iron into the trees or trying to change the pH of the soil. However, it is better to not plant these trees in our area. We are removing these trees and replacing them with varieties that don’t suffer from iron chlorosis.

Chlorotic Pin Oak that will eventually need to be replaced.

Bottom Line

Having trees in Kansas is a luxury, especially large long-lived trees that provide wonderful shade. Kansas weather – with its extremes-wet, dry, hot, cold, and wind – are all challenges for trees. The other thing to keep in mind is that our area was originally prairie. Prairie is what grew best here, with trees relegated to creek bottoms and wetter areas. So growing trees here will always be demanding and ambitious. Even if we do everything right regarding trees in the landscape, there is no guarantee that a tree will grow and thrive.

We will continue replacing and planting trees here at the Arboretum. I believe a diverse selection of trees – different from the trees we have lost – is the answer. We will continue to lose trees, because they are living organisms susceptible to all sorts of diseases and problems. But keep planting, folks!

Recommended trees and shrubs from Kansas Forest Service

Totally Tubular

Tube flowers occupy a special niche in the ecosystem. They cater to pollinators with especially long tongues, saving their nectar for the lucky few who can reach it. There are lots of tubular blooms at the Arboretum right now, so I thought we ought to take a tube tour and examine a few of my favorites up close.

Penstemon

With so many species to choose from, there is a Penstemon that’s right for everyone’s garden. Penstemon grandiflorus is a drought-loving species, shorter and with waxier leaves than its common, white-bloomed cousin Penstemon digitalis. Penstemon cobaea is the diva of the bunch: much showier and larger flowered, with flouncy pink bloom spikes that are more prone to falling over after heavy winds or rain (the floral equivalent of fainting onto a nearby chaise). But for all its drama, it is worth it for those huge, almost foxglove-esque flowers! All of them are a boon to hummingbirds in early summer.

Penstemon grandiflorus, pink tube shapes flowers on a reddish stem, airy and delicate looking.
Penstemon grandiflorus can range from white to light pink or lilac. It likes dry conditions and lean soil.

Honeysuckle

There is good honeysuckle and bad honeysuckle, and you should learn the difference! Invasive honeysuckle can come in two forms: bush or vine. Amur honeysuckle (Lonicera mackii) is the bush that has taken over woodlands and displaced many of our native species. It spreads by birds ingesting the berries then *depositing* them into new areas. Forests full of this stuff have decreased value for wildlife, and become an impenetrable monoculture and a maintenance nightmare. A look-a-like species, Lonicera japonica, is a vine with a similar flower. This too is invasive in our area, and can be found climbing trees and toppling fences. If you have these species on your property, please eradicate them and replace with a native honeysuckle like Lonicera reticulata — all the beauty of clustered, yellow tube blooms, but without the nasty invasive qualities. Or Lonicera sempervirens, a red flowering vine that grows vigorously and attracts hummingbirds. Both are drought hardy too!

Amur honeysuckle (Lonicera mackii) is a threat to our native ecosystems.
Lonicera reticulata blooms in May, and attracts many pollinators!

Amsonia (Common name: Blue star)


These small, star shaped flowers all cluster together to create a showy head of light blue in spring. But behind each star is a tiny tube! I’ve seen hawk moths, also known as hummingbird moths, flitting around these things for weeks now enjoying their nectar. Amsonia is easy to grow and likes full to part sun. Amsonia hubrichtii is thin leafed, almost needle-like in appearance while Amsonia illustris has a broader, glossier leaf. Both are hardy and can stand up to wind and drought, with excellent fall color.

Amsonia hubrichtii in fall color. Photo courtesy Walters Gardens.

Monarda

Monarda fistulosa flower, photographed by Brad Guhr

Also known as bee balm, this plant has a unique, pom-pom style bloom made up of individual flower tubes. In Kansas you will most likely find Monarda fistulosa growing wild, in ditches or near streams and ponds. Monard bradburiana is a shorter, slightly better behaved cousin. Both like full sun and medium soil moisture. Monarda didyma is a common eastern US species, and does well here if given a bit of extra water. I’ve seen lots of bees, butterflies, moths, and hummingbirds on this one so it gets an A+ rating for pollinator attraction.

A red variety of Monarda didyma shown with solidago (left) and a light purple Monarda fistulosa (right)

Tube-shaped blooms can be found everywhere if you start looking. They have a completely different structure than the classic radial flowers (roses, petunias) or composite flowers we are used to seeing (think sunflowers, echinacea, asters). The diversity of pollinators is as great as the diversity of flowers they feed on thanks to coevolution for thousands of years! Consider adding some tubular flowers to your garden, and enjoy their wacky, wonderful shape.

Echinacea Hybrids

I read an interesting article about Echinacea (coneflowers) the other day. It highlighted the highs and lows of the newfangled coneflower cultivars over the last decade or so. You know – the ones in oranges, reds, yellows and every shade in between. It seems that many coneflower breeders are doing some soul searching and they are coming full circle, back to producing hardier varieties of our wonderful native prairie wildflowers. 

Yellow coneflowers with Rudbeckia maxima and prairie dropseed

The Problems   

One of the biggest criticisms of these bright colored coneflower hybrids has always been their (lack of) persistence in the landscape. If you were lucky, you could get one or two years out of them before they disappeared.  Maybe one survived, but often you couldn’t find that variety anymore, because it had been replaced with another new form.  You would have to go back and start over again with another new coneflower. 

These coneflowers had other problems too. Winter kill, color fading and short bloom times soured gardeners toward coneflowers. They were not as reliable or persistent as their parents from the prairie. 

‘Julia’ is a hybrid coneflower sporting vibrant orange flowers on strong stems. Photo courtesy of Walter’s Gardens.

Problem solving

I can still remember offering those first forms such as Orange Meadowbrite and Razzmatazz. These diverged from the adapted forms of Magnus, Ruby Star, White Swan and Kim’s Knee High in dramatic fashion. We no longer only had pink and white coneflowers, but a warm rainbow of colors available on the market. Everyone wanted to try some in their yards. 

The problems quickly became evident and the novelty wore off. The coneflower fad stalled. Breeders began to look at coneflowers from a “whole plant” approach. A “good” coneflower was no longer identified by its unique color, but by the extended bloom times, heavy flower count, longer life span, and vibrant colors that don’t fade. Winter survival and multiple growing points were a focus as well. 

Most of these colorful coneflowers are produced through tissue culture production. However, some seed forms with reliable color, such as Cheyenne Spirit and the Pow Wow series have become a cost effective alternative to tissue culture forms of coneflowers. These seeded forms are consistent, vibrant, and affordable.

Going Forward

The trend for new coneflowers forms and colors shows no sign of slowing.  Innovation drives sales and new styles are always on the horizon.  One of my recommendations is to always start with the true natives first.  Pale purple coneflower (Echinacea pallida), narrowleaf coneflower (E. angustifolia), yellow purple coneflower (E. paradoxa) and purple coneflower (E.purpruea) are adapted to our climate.  They are always a good bet in the landscape.  Remember, the pollinators prefer these forms too. 

American lady butterfly on Echinacea angustifolia at Chase State Fishing Lake, near Cottonwood Falls, KS (Photo Credit: Brad Guhr)
Our native Echinacea pallida always has thin, reflexed petals and a pale purple hue.

We have been tinkering with coneflowers for a long time and that will continue. The simple prairie coneflowers that we have moved into our landscapes often don’t look the same. I believe these changes come with a price. Sure you get uncommon colors, but it is obviously not the same prairie plant. Do pollinators recognize them? 

If you want to try some of these new colors, choose wisely after doing some research.  One of the best new coneflowers, according to the Mt. Cuba coneflower trials, is Sensation Pink.

(Photo Credit: Brad Guhr)
Echinacea blooming along pond at Dyck Arboretum (Photo Credit: Brad Guhr)

Plant Apologies: Campsis radicans

I have accidentally been spreading some plant slander, and now it is time to apologize. Sometimes even we plant people get it very, very wrong! And so today’s post is all about Campsis radicans, aka the trumpet vine.

Illustration by Mary Vaux Walcott, CC0, via Wikimedia Commons

For years I have been railing against this plant.

“Ridiculously aggressive!”

“Impossible to get rid of!”

“It’s sold at these big box stores because they don’t care about the environment!”

While those things might be true in their own way, they leave out an important fact: It is NATIVE. Yes, Campsis radicans is a native vine that is found from Maine to Florida and west to Kansas. I have said many times that is was invasive, imported from far flung lands, and is a plague upon our forests. And boy was I misinformed. Remember, the word ‘invasive’ really should be reserved for non-native plants that have reproduced in and disturbed the local ecosystem. Aggressive is a better, more accurate way to describe a plant’s behavior if it spreads readily, but is native to our area. Invasive, as a horticultural term, means something about its origins and introduction into a new place.

Photo from Wikimedia Commons

Many Good Traits

This plant blooms July through August, attracting a whole host of long-tongued pollinators. Blooms can be red to orange, and its slightly sweet scent is great for trellises near the patio. It grows quickly, so can create fast shade over a pergola. The foliage is attractive and lush, and serves as a host plant for several species of moth.

The showy flowers attract bees and hummingbirds. Photo by Rob Hille, Public domain, via Wikimedia Commons

Some Not So Good Traits

My information about its origins was bad, but my warnings about its behavior were spot on. It is fast growing to a fault, and can be seen toppling fences and commandeering telephone poles. To keep this thing in control means relentless pruning. Growing right before your eyes, trumpet vine can easily climb 10 feet or more in a summer. It does not play well with others, and will send runner roots out into nearby garden areas. And don’t forget its seeds! A single pod can have 600+ seeds.

So, Campsis, I am sorry. You are a native vine with your own beautiful and ecosystem-sustaining qualities! Though I will still keep it out of my own garden, I can see it has a rightful place in a forest edge or hedgerow, and I will never call it invasive again!

Plant Profile: Native Irises

When we think about spring, bearded irises often come to our minds. These resilient harbingers of spring often carry personal meaning for gardeners. Many have been shared and passed down from family and friends through the years.  For my family, we have nice yellow and white bearded irises from my wife’s mother. They are beautiful reminders of the past that now brighten the spring landscape. We also have some of the more traditional lavender and purple bearded iris. These imported forms come in thousands and thousands of colors and sizes, with more developed every year. 

There are over 300 species of irises in the world and there are six different sizes of bearded iris alone.  Most of these are native to Europe and Asia. Even though these exotic iris enliven the developing spring landscape, some of the native forms of iris deserve a place in the landscape too. Here are a few garden worthy native Irises that I would recommend.

Dwarf Crested Iris-Iris cristata

If you are looking for a shade tolerant groundcover, this diminutive mat-forming wildflower fits the bill.  The underground rhizomes slowly spread in and around other shade loving perennials.  It has the distinctive narrow pointed leaves that iris have only smaller. In spring, plants brighten the ground with myriads of small blue-violet irises.  This spring beauty prospers in woodland settings with average well drained soils.

Iris cristata ‘Eco Bluebird’ Photo credit https://en.wikipedia.org/wiki/Iris_cristata

Copper Iris-Iris fulva

This unusual iris has coppery or reddish flowers in late April through June. The beautiful flowers have three sepals and three petals each arching away from the stem. Like traditional iris, copper iris has bladelike leaves along the flower stems that emerge from a rhizome. They grow two to three feet tall and spread one to two feet. They prefer wetter conditions and thrive in swamps and bottomland forests, and along the edges of sloughs, ditches, canals, and ponds, often in shallow water. It is a species that should be used more often in home gardens, rain gardens, ponds, and water features. 

Iris fulva

Photo Courtesy
Blue Flag Iris-Iris virginica shrevei

There are several native iris under the title of blue flag iris.  This iris, commonly known as “Southern Blue Flag”, has a native range in most of the Eastern United States in wetlands and marshes.  In June, the striking pale lavender blooms with yellow throats open above the foliage.  We have some of these growing on the pond edge in moist, sometimes shallow water.  It spread by rhizome to form attractive colonies.  Mature height is two to three feet with clumps spreading several feet from the original plant.  Give it full sun to partial shade. The key to success for this native iris is adequate or consistent moisture. 

Iris virginica-Southern Blue Flag Iris Photographed at Ranch North Woods Preserve, Pulaski County, Arkansas
http://By Eric Hunt – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=72555262

Other Irises

Iris ‘Black Gamecock’ (Louisiana hybrid), Iris versicolor (Northern blue flag), and Iris brevicaulis (blue flag).

Many of these native species of iris are threatened by habitat loss.  They are rare or are becoming more rare. Their fragile ecosystems can easily be damaged, so be careful not to disturb iris that you do find in the wild.  Admire and take pictures, but don’t try to dig them up because most native irises are extremely difficult to transplant. Most of these plants will not survive the shock of dividing and transplanting. For this reason, on national forest lands, it is illegal to dig or pick the irises.  If you have a spot, plant a few native irises grown by reputable nurseries, so you can appreciate, conserve and enjoy these beautiful wildflowers.

We will have several of these iris species available at FloraKansas Native Plant Days.

2023 Native Plant Guide

Fun facts from Bonnie Neubrand’s 2023 calendar:

  • Iris symbolize: Eloquence, hope, wisdom, communication and faith.
  • 325 species of iris worldwide
  • 50,000 registered varieties of iris
  • There are two groups of iris – bearded and beardless
  • Size varies from 5 feet tall to less than 8 inches tall
  • Origins in the United States trace to Virginia where bulbs were probably planted in the 1600’s
  • Iris bulbs can be toxic to pets

Keystone Natives for the Food Web

I have been reminded over the past few weeks about about the importance of keystone natives. There is a growing body of research that touts the benefits of keystone species of trees, shrubs, wildflowers and grasses to the food web. According to Doug Tallamy, landscapes without keystone plants will support 70–75% fewer caterpillar species than a landscape with keystone plants, even though it may contain 95% of the native plant genera in the area. Keystone plants must be included in your native garden design.

Take a look at Doug Tallamy’s book, Nature’s Best Hope: A New Approach to Conservation that Starts in Your Yard for more data.

The food web includes, plants, insects, pollinators, birds, lizards, toads, frogs, and mammals, from rodents up through bears.  Each is reliant on the other for their survival. Tallamy focuses much attention on trees that support the food web such as oaks, cherry, cottonwood, willow, and birch.  However, there are many native perennials that are also key components of this food web. To provide a solid foundation for a healthy food web in your garden, start with this list of native wildflowers to include in your landscape:

Goldenrods (Solidago sp.)

These summer blooming wildflowers with bright yellow flowers can be striking in the landscape. However, they have a reputation for causing allergies. In truth, this is unlikely because goldenrod pollen is large and heavy and is not carried by the wind. Rather, it is giant ragweed that is spreading pollen through the air at the same time. The plant is insect-pollinated by many wasps, moths, beetles, honey bees, monarch butterflies and other beneficial pollinators searching for a sip of nectar.  In total, 11 specialist bees and 115 different caterpillars need these plants. There are around 50 species of insects with immature forms that feed on the stems of goldenrod.

I like Solidago rigida, Solidago nemoralis, Solidago ‘Wichita Mountains’, Solidago canadensis ‘Golden Baby’, and Solidago ‘Fireworks’ for sunny areas. For shade, I choose to plant Solidago odora, Solidago ulmifolius or Solidago caesia.  It is safe to say that goldenrods are powerhouse plants that deserve a place in your native garden.

Rigid Goldenrod with red switchgrass

Asters

A diverse genus that supports 112 species of insects, asters are a valuable late-season (September – November) source of pollen for bees and nectar for bees and butterflies. During the summer, the asters are host plants to the caterpillars of some of the crescent and checkerspot butterflies. As summer wanes, asters start blooming with colors of white, purple, and pink depending on the species.  Fall provides a unique challenge for pollinators and asters help with both migration and overwintering butterflies and bees. 

A few of my recommended forms are Aster oblongifolius ‘Raydon’s Favorite’ and ‘October Skies’, Aster novae-angliae varieties, Aster laevis and Aster ericoides ‘Snow Flurry’ for sun.  In a shady area, try Aster divaricatus ‘Eastern Star’, Aster cordifolius, and Aster macrophyllus.

Aster ‘Raydon’s Favorite’

Sunflowers (Helianthus sp.)

There are eleven species of sunflower recorded in Kansas. These wildflowers are not usually fit for a formal garden setting, because they spread vigorously by seeding and rhizomes.  They have a tendency to push out other desirable plants.  However, they support 73 species of insects, so we maybe need to find a place for them. 

I’m not referring to the large-headed annual cultivars you see growing in a field, but rather the true native perennials with bright yellow flowers seen growing along the roadside in the late summer and early fall.  Plants provide lots of nectar and pollen, and the seeds are eaten by many birds and other wildlife. I would encourage you to try a few sunflowers in the peripheral areas of your yard where they can spread out and have room to roam. 

Maximillian Sunflower and Big Bluestem

Milkweeds

Monarchs are in peril. Milkweeds are one of the answers to reversing their plight. By planting more milkweeds, monarch will find these larval food sources more readily. Milkweeds are larval host plants for Monarch and Queen Butterflies and the Milkweed Tussock Moth. Many bees, wasps, butterflies and beetles visit milkweed flowers for the nectar. Milkweed plants typically produce a lot of nectar that it is replenished overnight. Nocturnal moths feast at night and other pollinators flock to these important plants during the day. 

Choose butterfly milkweed (Asclepias tuberosa) or green antelope horn milkweed for your formal garden and common, Sullivant’s, or whorled milkweeds for the outskirts of your property. 

Newly hatched monarch caterpillar on common milkweed.

Blazing Stars (Liatris sp.)

Liatris are very important wildflowers. The vibrant purple blooms in summer support many great insect species. They are quite adaptive with different species growing in dry to moist soil conditions. There is literally a blazing star for just about every garden setting. 

I prefer Liatris pycnostachya and Liatris aspera, but many others, including Liatris ligulistylis and Liatris punctata, are nice too.    

Liatris pycnostachya

Planting just natives is not enough. Garden designs and plant communities must contain at least some keystone plants to positively impact the food web. This is the start of a list, but there are certainly more plants to choose from.  Check out Keystone Natives for the Food Web-Part 2 and Keystone Natives for the Food Web-Shrubs.

March Gardening Checklist

While March can still be cold in Kansas and we can get some significant snow and ice, there are still opportunities to spend time in your garden. Here is a March gardening checklist that will prepare your garden to thrive in the coming year.

Prune trees and shrubs

This is a perfect time to be pruning trees and shrubs. Maybe there is a branch that is always in the way while you mow, or shrubs that are encroaching on a walkway. Cut them back. Keep in mind to only prune shrubs that flower on new wood. Pruning shrubs like forsythia and lilacs will remove blooms for this spring. Spring blooming shrubs can be pruned after they are done blooming in late April or May so they have time to set new buds for next year. Check out this blog by Katie, Old Wood, New Buds: A Pruning Guide.

Don’t lose your lilac blooms, prune at the perfect time! Photo by AnRo0002 (Own work) [CC0], via Wikimedia Commons.

Cut back flower beds

Now through March is the time to trim back ornamental perennials and grass stalks to clear room for new growth. By cutting these plants back it you allow sunlight to reach the crowns and warm the soil. We have talked about it several times, but it is worth repeating – if you can help it don’t carry stalks away from your garden. Leave them as natural mulch. These stems and stalks harbor native pollinators that you want to keep in your landscape. If thatch is too thick, remove it to an obscure place in your yard or along the alley.

Northwind Switchgrass cut back and ready for spring

Apply compost to soil

If you haven’t already, empty out your compost bin and put it on your garden. Prepare your garden soil if it’s dry enough to work. Dig in compost and other amendments when your soil can be worked. Only do this if your soil is dry enough.

How do you know when it’s safe to work the soil? When a ball of soil crumbles easily after being squeezed together in your hand, it’s dry enough. With our clay soils, avoid compacting your garden soil. Wait until it’s dried out before tilling, planting, or even walking in the garden beds.

Loosen mulch

Mulch has a tendency to fuse together, especially with mulch more than a couple inches thick. This cake layer along the top resists moisture penetration and seals off the soil, restricting good air exchange. It is good each year to rough up the mulch with a fork or rake to break that seal. This will open up the soil to moisture and positive air movement. Tree and shrub mulch rings and shrub borders will benefit the most from this exercise. While you are at it, maybe a fresh layer of mulch is needed. I typically have 2-3 inches of mulch around these woody plants.

Arizona Cypress nicely mulched on a berm.

Continue to gather ideas

There is so much information available to gardeners these days. Choose plants that create habitat and attract wildlife to your yard. Review your garden journal from last year. Read horticulture magazines. Attend the lectures and presentations at your local garden shows such as the Harvey County Garden Show on March 25 and 26 here at the Arboretum.

Regardless of what season the calendar says, there is always something to do in the garden. Spring is coming, so now is the time to get ready. I don’t know about you, but I am ready to see some blooming plants again.

Yellow crocus in the xeric garden brighten a winter day

Native Grasses FAQ

After my Native Plant School class last week, there were several good questions about native grasses that are worth addressing again.

Question 1: How do you clean up native grasses in the late winter (Feb-March)?

Grasses tend to remain attractive well into winter, providing texture, movement and continuity to the garden. However, they eventually need to be cut back in preparation for spring. We use a gas powered hedge trimmer because we have so many grasses to cut back. The stems are tough but the trimmer easily cuts through them especially compared to hand pruners or loppers.

Starting at the top of the grass, we just cut through the grasses back and forth at 2-3 inch intervals until the grass is cut down to 2-4 inches off the ground. We then scatter the cuttings around the base of the grass so that it is not too thick. The trimmer makes quick work of a five foot grass. If the pile at the base of the grass is too thick, we scatter the clippings someplace else in the garden. This way you are keeping all those overwintering insects in your yard.

In our recent Winter Lecture Series, guest speaker Heather Holm suggested an even more insect-centric approach to spring garden clean up. Gain access to her presentation HERE.

Northwind Switchgrass cut back and ready for spring

FUN FACTS!

  • There are more than 400 different native bee species in Kansas.
  • An estimated 30% of native pollinators nest in pithy stems of plants such as native grasses and wildflowers.
  • Dead branches or logs decaying provide excellent habitat. Create a small bush pile for birds and pollinators. Overwintering butterflies and ground nesting bees can be found in brush piles and the decomposing wood gives fireflies a place to lay their eggs.
  • Nearly 70% of native pollinators are ground-nesting, burying into the soil to reproduce. Open soil without landscape fabric or two to three inches of mulch allow these burrowing insects to easily access the soil.

Question 2: When is the best time to plant buffalograss?

Buffalograss is a native warm-season sod forming grass. It needs at least six hours of direct sunlight for it to germinate and grow healthy. It spreads by stolens and has fine blue-green leaves. New seeded forms of buffalograss have been developed over the years such as Cody, Bison, Bowie, Plains, Topgun and Sundancer. Most of these seed forms are available online and some are available at regional Farmers Cooperatives. Seeding can be done anytime from May through August 15 as long as the soil temperatures at a two inch depth are above 60 degrees. Check out Buffalograss: Five Keys to a Successful Planting on our website.

Buffalograss Interior of Arboretum

Question 3: Can you list out the heights and mature sizes of the grasses?

One of the key components of a successful native landscape design is situating grasses. Repeating taller grasses at regular intervals looks formal while these same taller grasses at irregular intervals is relaxing and less formal. Grasses unify and blend your landscape together and they are wonderful companion plants with other wildflowers and shrubs.

  • Short= 4-24 inches, Examples: prairie dropseed, blue grama, pink muhly, sideoats grama, june grass, “Blonde Ambition” blue grama, purple love grass, and Nassella tenuissima,
  • Medium= 2-4 feet, Examples: Little bluestem, Little bluestem cultivars, Sideoats grama, Blonde Ambition blue grama, Northern sea oats, Pink Muhly grasses, “Cheyenne Sky” switchgrass, “Shenandoah” switchgrass, and sand love grass (Eragrostis trichoides).
  • Tall= 4-7 feet, Examples: Big bluestem and cultivars, Indian grass and cultivars, Eastern gamma grass, prairie cordgrass, switchgrass and switchgrass cultivars.
Indiangrass against the Kansas sky. Photo by Brad Guhr.

Advantages to Using Ornamental Grasses in the Landscape

As I was preparing for my next Native Plant School class on the Wonderful World of Grasses, I was reminded why I love grasses in the landscape.  Here are a few thoughts about why ornamental grasses are such an important component of a successful habitat garden.

Versatility

There is so many different ways you can use ornamental grasses in the landscape.  Distinct grasses introduced into your landscape will serve different purposes.

I love the way shorter grasses like prairie dropseed look along a walkway or border. Combine these grasses with shorter perennials and it really sets off the edge of a planting bed. Ornamental grasses are a great alternative groundcover to traditional turf grass such as fescue, too.

I use larger ornamental grasses typically as a backdrop for medium to tall perennial wildflowers or as a screen to hide something like a gas meter or transformer.  These taller varieties billow out to create volume as they grow to fill in spaces. They also can be used to punctuate the design as focal points.  Grasses are structure plants that mix well with other seasonal wildflowers such as black-eyed Susan or asters.

Varied Appearance

When it comes to ornamental grasses, there is one for just about every landscape situation. The distinct features, varied heights, forms, colors and varieties give you options to diversify and contrast plants in your landscape. Fine or coarse foliage of green, blue, purple, tan and red hues planted together with interesting seedheads add visual interest and texture in winter. All these features lead your eyes through your outdoor space. As the grasses transition into fall, many develop attractive fall color and interesting seed heads. In the winter, taller grasses capture snow and move with the gentlest breeze.

Sorghastrum nutans GOLDEN SUNSET® (‘MNYG318153’ PP33776) Photo by Walters Garden
Schizachyrium scoparium ‘Twilight Zone’ PP27432 Photo courtesy of Walters Garden

Easy Maintenance

Over the past few years, more and more people are including ornamental grass in their landscape. As we have said they are versatile and beautiful. They are also reliable in our unpredictable Kansas climate. Grasses are a low-maintenance landscape option once established. The deep roots help grasses combine well with other perennials. They don’t need fertilizer because that will make them grow quickly and flop. They grow on their own without the need for pruning or maintenance. We usually cut our grasses back in late winter around February or March in preparation for spring.

Environmental Benefits

Photos by Iralee Barnard

Most ornamental grasses and especially warm season grasses such as switchgrass and big bluestem are resistant to heat and drought. They don’t require a lot of extra moisture through the growing season which conserves water in the garden. Overall, native or ornamental grasses are pests or disease free which reduces the need for pesticides, so you don’t pollute local waterways.

As I mentioned earlier, grasses have deep root systems that are great at holding soil and eliminating erosion. Probably the biggest advantage of including ornamental grasses in your gardens is that they create habitat. Wildlife and pollinators use grasses for overwintering, resting, and sourcing food. Grasses are familiar elements of the natural environment for wildlife. Add a few grasses and see what and who arrives in your yard.