Plant Profile: Pink Muhly Grass

Fall is the best time of year to admire the beautiful regalia of native grasses. During the spring and summer, these grasses blend into their surroundings. As autumn deepens, the wonderful fall color and attractive seed heads of these grasses are on full display.

One of the most talked about grasses this fall has to be pink muhly grass (Muhlenbergia capillaris). A few years ago on the sidewalk in the northwest corner of the Arboretum, we established a couple groupings of these plants. This year, these swaths are topped with vibrant pink blooms.

Pink muhly with Wichita Mountains goldenrod

Pink muhly grass is not only a beautiful ornamental grass, but it is also low-maintenance. We have not done much to keep these grasses going this growing season. It gives you the best of both worlds, a showy plant that doesn’t require much time and attention.

These plants establish relatively quickly, either planted in the spring or in the fall. If you are planting in the fall, plan ahead by getting them in the ground at least a month before the expected initial frost. They are a warm season grass that needs soil at least 60 degrees to continue rooting.

In the spring and summer, the rounded, slender, long shoots of grass are dark green in color. As fall approaches, the plant produces soft, fuzzy flowers in pink or pinkish-red hues, with an appearance resembling cotton candy. As winter grows near, the flowers lose their color, but the dried plumes are still attractive.

Muhlenbergia capillaris grows well in sandy or rocky woods and clearings with good drainage. It is native to Kansas and states south and east. We grow the straight species, but the cultivar ‘Regal Mist’ is another popular variety. Other beautiful cultivars include ‘Pink Flamingo’ and ‘White Cloud’. Planting in large drifts is breathtaking.

While not as well-known as some of the other native grasses, it should be used more in landscapes because of its tolerance to poor soil and dry conditions. It needs good drainage especially during the winter, but is quite adaptable once fully established. As the clumps develop excessive thatch after three or four years, division may be helpful. Perfect for slopes; great in a container; beautiful when tucked into cut-flower arrangements.

Sunlight on pink muhly grass with side oats grama in the foreground.

For next spring, put this grass on your bucket list. You will not be disappointed. The soft watercolor effect will stop you in your tracks.

Wonderful Autumn

This time of year a person interested in plants can get very tired and rundown.  I certainly have been dragging.  The relentless heat and drought has many plants stressed and prematurely going dormant.  We have been watering as we can but we can’t water everything.  As we wait for rain and hope that our little plants can hang on, there is still beauty happening all around us. 

I was reminded of this last week as we hosted several groups of fifth graders.  We stopped at some fall blooming asters including purple New England asters that were teaming with hundreds of different pollinators.  Monarchs were passing through too and they added to the excitement at what they were experiencing from this landscape.  These pollinators were eager to find nectar in this created habitat.  It reminded me anew why landscaping with native plants is so important. These children were amazed at what they saw. Their awe and wonder at the diversity of pollinators really impacted me. Sometimes we need to see things from the eyes of children.  

We like the aesthetics these landscapes provide for our homes, and businesses, but these patchwork habitats are needed and sought out by many different pollinators.  Here are some eye candy for you to enjoy. 

Bordered patches are commonly found throughout the southwest US and Northern Mexico, but can be found in Kansas through late fall.

Our landscapes can be frustrating and troublesome at times. These landscape can also be therapeutic and healing. Maybe you need to step back like I did this past week and take in the simple beauty all around us. Even though you may be suffering from landscape maintenance fatigue, you are doing something vitally important both for you and the wildlife that is attracted to you prairie garden.  Don’t lose heart. 

Monarchs congregating in the Arboretum Amphitheater today. Hundreds of them. This was just one branch. WOW!!

Plant Profile: Pitcher Sage, Salvia azurea

During the doldrums of late summer, light blue flower spikes thrusting skyward along Kansas roadsides and prairies provide welcome contrast to the yellows of the state’s many sunflowers.  Pitcher sage, also known as blue sage or pitcher plant, is a delicate looking prairie native with ironclad constitution. 

Salvia azurea, also known as blue sage, is a member of the MINT FAMILY.

Pitcher sage is a somewhat common plant in the rocky areas of the tall and mixed grass prairies. This plant is an erect, hairy perennial ranging in height from one and a half to four feet with short, thick rhizomes (horizontal underground stems). Very adaptable to garden situations, it prefers drier soil in full sun. In sandy sites it has been known to self-seed, but this is seldom a problem in clay loams. The crowns can slowly broaden from rhizomes as the plant matures. 

Pitcher sage blooms from late July to early October, although peak bloom is early September in most years. It is blooming right now in our Prairie Window Project in the south part of the Arboretum. The light blue flower color is common in prairies around south central Kansas. There is a cultivated variety, Salvia azurea “Grandiflora,” that displays an intense deep blue flower. Once established, it requires water only during extended dry periods. 

Besides the unique light blue coloration, the flowers possess an unusual mechanism to ensure cross-pollination. The corolla is lobed with a narrow concave lip covering the style (female) and the anthers (male) which mature at different times in the same flower. The lower lip is broad and protruding, providing a landing pad for visiting honey bees, bumble bees and other pollinators.  The bee grasps the platform, thrusts its head down into the throat of the flower and pushes its sucking mouth parts into the nectar glands. By this action, the bee is simultaneously pushing down on the structure at the base of the stamens. This causes them to descend from the upper lip spreading pollen on the bee’s back. As the bee visits other flowers, it spreads pollen to receptive styles. 

Bumble bee in search of some nectar.

The Arboretum grows pitcher sage for its late summer color and the bee activity it provides.  The plant is a bee magnet in full bloom. It is always entertaining to watch lumbering, black and yellow bumble bees wrestle their way into the flowers in search of nectar while unwittingly carrying the promise of another seed crop on their striped backs.   

Plants for hillsides and slopes

One of the more common landscaping conundrums is deciding what to plant on steep slopes or hillsides. These areas require plants that can establish quickly, have fibrous root systems, that hold soil to control erosion, are tolerant of fluctuating soil moisture and potentially poor nutrient availability, and require little care once established.

Slopes and hillsides are already challenging because of sun exposure, and the degree of the slope only exacerbates the problem. Establishing plants from seed is the most economical choice, but is also the most subject to erosion for the first 3 to 5 years until plants get established. Often, turf grass such as fescue, buffalograss, or bermuda grass is the first groundcover choice for keeping soil in place, but mowing these sloped areas can be a challenge, maybe even dangerous. Turf does not create much habitat for wildlife and pollinators either.

There are many plants that will establish cover more quickly than seed. These native plants offer a lower maintenance alternative to a mowed lawn. The following list is just a start. Remember to plant more densely (1-2 feet apart) so the area gets completely covered with plants quickly.

Grasses

The following grasses, with their extensive fibrous root systems are ideal plants to stabilize a steep area and prevent soil erosion.

  • Andropogon geradii (Big Bluestem)
  • Bouteloua curtipendula (sideoats grama)
  • Chasmanthium latifolium (River oats)-Can grow in sun or shade but is aggressive. It will spread by seed and rhizomes to crowd out most other plants.
  • Elymus canadensis (Canada wildrye)
  • Panicum virgatum (Switchgrass)
  • Schizachyrium scoparium (little bluestem)
  • Sporobolus heterolepis (prairie dropseed)
Little Bluestem with Aromatic Aster and New England Aster

Wildflowers

  • Achillea millifolium Yarrow
  • Allium cernuum Nodding onion
  • Amsonia sp. Blue star
  • Aquilegia canadensis Columbine
  • Asclepias tuberosa Butterfly weed
  • Baptisia australis False blue indigo
  • Dalea purpurea Purple Prairie Clover
  • Echinacea purpurea Purple coneflower
  • Eutrochium (Eupatorium) maculatus Joe-pye weed
  • Filipendula rubra Queen-of-the-prairie
  • Liatris pycnostachya Prairie blazing star
  • Liatris spicata Dense blazing star
  • Rudbeckia sp. Black-eyed Susan
  • Penstemon digitalis Penstemon
  • Symphyotrichum oblongifolium Aromatic aster
  • Solidago sp. goldenrod
  • Tradescantia ohiensis Spiderwort
  • Veronicastrum virginicum Culver’s root
Amsonia ‘Butterscotch’ and Aster ‘Raydon’s Favorite’ with mulch between plants to control erosion.

Trees and Shrubs

  • Amelanchier canadensis Serviceberry
  • Cercis canadensis Redbud
  • Coruns sp. Dogwood
  • Crataegus viridis Hawthorn
  • Heptacodium miconioides Seven Son Flower
  • Ilex verticillata Winterberry holly
  • Lonicera reticulata Grape honeysuckle
  • Prunus Americana Wild Plum
  • Prunus sp. Sand cherry
  • Prunus virginiana Chokecherry
  • Rhus aromatica Fragrant sumac
  • Sambucus canadensis Elderberry
  • Viburnum prunifolium Blackhaw Viburnum

If the erosion is already very serious, you might want to consider using erosion-control blankets to stabilize the erosion area until the plants can take over the job. The erosion-control fabric works by slowing the runoff water and allowing sediments to fall out rather than be washed away. Choose a mat that will decompose over time, e.g. straw or jute, rather than something made of plastic. Start by slicing a small opening in the mat so plants can be put into the soil beneath. I recommend hand watering during establishment as much as possible since sprinkler irrigation can increase soil erosion.

For more gentle slopes, heavy mulch or pea gravel can be used to control erosion during establishment. Each slope situation is unique, but if you can, the best strategy for stabilizing a slope with plants is to establish vegetation at multiple levels—plant trees, shrubs, grasses and wildflowers. A multi-level canopy will do the best job of intercepting and slowing precipitation before it hits the ground, reducing surface erosion. Different vegetation types also provide both deep and spreading roots that stabilize the entire soil profile. Generally, it takes 2-4 years to get these plants fully established and roots anchored into the slope.

Slopes covered with a variety of grasses including switchgrass and fountain grass at Wichita Art Museum. Photo by Brad Guhr

Summer Garden Checklist

Kansas summers can discourage even the hardiest gardeners. However, taking time to manage your garden now will help your garden later. Here’s my Summer Garden Checklist for the Kansas gardener.

Control Warm Season Weeds

Summer brings with it a new set of weeds to control. Hot weather germinates summer annuals like crabgrass, foxtail. Nutsedge and other weeds invade your lawn and landscape as well. Manage weeds using nonchemical methods such as cultivation, hand weeding, or mowing; use toxic chemicals as a last resort. 

Mowing regularly and occasionally edging along sidewalks and walkways is needed to ensure your lawn is not overrun with weeds. In a landscaped bed, hand pull any of these weeds, especially if they have seed heads.  It is so important to not let these weeds go to seed. Stay vigilant even though the summer heat tries to squash your enthusiasm. A little extra effort now will make your garden better this fall and into next year. 

Crabgrass in tree mulch ring controlled with roundup: one treatment should clean up the mulched area and keep it weed free the rest of the season.

Be Water Wise

To reduce evaporation, water when temperatures are cooler and air is still, usually in the early morning. Water deeply to moisten the root zone, but infrequently. About an inch of water each week is a good rule of thumb!  If you have invested in container plants, they will need daily watering, as soil in pots can dry out quickly and damage plant roots on hot summer days.  Each of our gardens have indicator plants that show stress first, let these plants be your guide as when to water.  For new planting started this spring, water when the top one to two inches of soil is dry.  Remember it takes three to five years for sustaining roots systems to develop for most native plants.  Supplemental watering is necessary to encourage growth and root development in these young plants. 

We use pressure compensating 1/2 inch soaker hoses to efficiently water trees, shrubs and a few flower beds. Each emitter puts out 1 gallon of water per hour.

Prepare for seeding

If you are wanting to establish native prairie plants from seed, now is a great time to prepare your area.  Mow your area short (1-2 inches). Control perennial weeds such as bindweed or Bermuda grass by carefully spraying the area with Roundup. It will take several applications to get these problematic weeds under control. If you can see soil, tillage is not necessary. If you can’t see soil, till lightly to expose some bare soil. Remember, each time you till, you bring up more weed seeds, so tread lightly. 

Measure your area and order a seed mixture that matches your site. A good seed mix ratio of wildflower to grass is 70% wildflowers to 30% grasses. Grasses tend to dominate over time, so this ratio will give the wildflowers a good start. We typically spread seed in November and December after the soil temperature has dropped enough to discourage germination. The natural freeze/thaw of the ground will work the seeds down into the soil to the proper depth for germination next spring. 

This is the seed mix we established along our newly renovated path.
Sidewalk edge planting: We mixed some sand with the seed mix to make it easier to distribute. We then let the natural freeze/thaw of the soil plant the seed for us through the winter. Germination occurred the following spring when soil temperatures rose above 60 degrees.

Trim

Now is a great time to trim back perennials that have become unruly. Perennial and grasses that are encroaching sidewalks, paths, and structures can be sheared back to size. If this is a problem every year, you may consider moving the taller plants to another spot. Plants can be divided next February or March before they start to actively grow. 

Low hanging branches from trees can also be pruned. It is getting late in the season to do much pruning on shrubs. New growth may not have enough time to get hardened off before cooler/colder weather.  If a branch or shoot is in the way, then prune it, but prune sooner rather than later. If you can wait until the shrub goes dormant this fall, then wait. 

As a general rule, early spring flowering shrubs such as forsythia, lilac and spirea should be pruned right after they are done blooming since they bloom on the previous year’s growth. Pruning right after blooming will allow the shrub to grow and develop a new set of buds for the next spring. 

A large compass plant that needs to be trimmed away from the path.

Finally, remember “WHY” you are gardening; creating habitat, conserving water, aesthetics, attracting pollinators, attracting birds and other wildlife or curb appeal. Let your “WHY” reinvigorate you to take care of a few extra tasks that will give your landscape a boost. Don’t sweat the small stuff and don’t forget to step back to enjoy what you are trying to create. If it is all work and no enjoyment, then what is the point.

Pale purple coneflower with a common buckeye butterfly. Fun to watch!

Butterfly weed: Fun Facts

One of the most iconic prairie wildflowers is Asclepias tuberosa, commonly referred to as butterfly weed or butterfly milkweed.  From May to July, its bright orange flowers dot the prairie landscape. These attractive flowers are a magnet for many different pollinators, including the monarch butterfly.

Butterfly weed can be found in dry fields, meadows, prairies, open woodlands, canyons and on hillsides. It grows on loamy and sandy, well-drained soils, in areas that provide plenty of sun. It is consistently the most sought after prairie wildflower for a garden and the flowers work well in bouquets.

Darker orange blooms with red pigment in the flower

Butterfly weed (Asclepias tuberosa): Did You Know…?

  • The flower color in Asclepias tuberosa ranges from deep red-orange to a rich yellow, depending on the amount of red pigment which is superimposed over the yellow carotenoid background pigments. The flower color has nothing to do with the soil type.
  • This species can be found in the eastern two-thirds of the state of Kansas.
  • Butterfly weed is also known as “butterfly milkweed”, even though it produces translucent (instead of milky) sap.
  • The scientific name Asclepias comes from Asklepios, the Greek god of medicine. tuberosa refers to thick tuberous roots which make it very difficult to transplant from the wild.  Please don’t dig mature plants from the prairie. 
  • Root of butterfly weed was used in treatment of pleurisy, bronchitis and other pulmonary disorders in the past. Don’t try this at home. 
  • Butterfly weed can be also used in treatment of diarrhea, snow blindness, snakebites, sore throat, colic and to stimulate production of milk in breastfeeding women. Again, don’t try this at home. 
  • The small individual flowers consist of 5 petals. Each milkweed blossom is equipped with a trap door, called a stigmatic slit. When insects land on their pendulous flowers, they must cling to the petals as they feed on nectar. As they forage on the flower for nectar, their foot slips into the stigmatic slit and comes in contact with a sticky ball of pollen, called a pollinium. When the insect pulls its foot out of the trap door, it brings the pollinium with it. Eventually, the insect will move on to the next flower. Should that same foot slip back into another milkweed flower’s stigmatic slit, the pollen can be transferred and pollination is completed.  This process is quite amazing to watch. 
  • Typically, it takes three years for a butterfly weed to start producing flowers.
  • The long narrow fruit pods develop later in summer. These hairy green pods ripen and ultimately turn a tannish-brown in the fall. Each pod contains hundreds of seed equipped with silky, white tufts of hair. As the pod dries and splits in the fall, the seeds are carried away by the breeze. Those white tufts of hair act as tiny parachute-like structures that disperse the seeds. 
  • As with other milkweeds, butterfly weed will attract aphids; you can leave them for ladybugs to eat or spray the insects and foliage with soapy water.
Gorgone Checkerspot

Butterfly weed is a garden worthy wildflower. It doesn’t spread aggressively like other milkweeds, but rather stays as a nice upright clump. Its many ornamental and functional assets, plus its rugged character will make it a focal point in the summer garden for years to come. You will be rewarded as pollinators seek out the beautiful iconic flowers of this native wildflower. Give it a try!

Orange and yellow butterfly weed blooming in the same flower bed
“Hello Yellow” butterfly weed

Do You Have Nutsedge?

This time of year, yellow nutsedge (Cyperus esculentus) and purple nutsedge (Cyperus rotundus) become problematic in the landscape. These problem weeds have triangular grass-like leaves and form colonies if left unchecked. It is not a grass, but rather a sedge. The key identifying feature is the triangular stem in cross section, as opposed to a round cross section in grasses. 

In Lawns

Nutsedge is a common weed in lawns with waterlogged soil, and its presence often indicates that drainage is poor, irrigation is too frequent, or sprinklers are leaky. Once established, however, it will tolerate normal irrigation conditions or drought.  Established nutsedge plants grow faster than many lawn grasses, so it is often noticed when it outgrows the surrounding grass. The leaves are bright green and have a waxy appearance in summer when surrounding lawn grass may be a lighter green.

Management in Lawns

As with most weeds in lawns, the best defense is to maintain a healthy, dense turf that can compete and prevent weed establishment.  Water lawns on an as-needed basis, not on a regular schedule. Overwatering increases disease and provides a better environment for nutsedge to grow. 

For larger infestations in lawns, spot spray with a liquid, selective herbicide that contains the active ingredient: Common Name: Halosulfuron; Trade Name: Manage, or Sedgehammer and others or Common Name: Sulfentrazone.  Mixing these herbicides with a non-ionic surfactant that breaks down the waxy leaf coating to the chemical is more effective. 

In Mulch

Nutsedges thrive in areas with little or no competition.  In mulch rings around trees and between flowers offer ideal conditions for large colonies to form. Actively growing stands of nutsedge have extensive root systems that can reach as deep as four feet. Nutsedges produce underground tubers and runners that make it difficult to pull out of the ground. Each of these can produce another plant if not completely removed.

Mechanical management

Digging out or using an appropriate weeding tool to remove the underground ‘nutlets’ is the primary means of mechanical control of nutsedge. This is a viable option at the beginning of an infestation and on young weeds.  If you want to avoid spraying chemicals for control of nutsedge, you need to relentlessly pull the plants every time a new plant emerges.  It is most active in May through October.  We have also smothered nutsedge with cardboard and two to four inches of mulch. Nutsedge may emerge again next year after the cardboard has decomposed.

 

Spraying

We have had success spraying nutsedge.  We use Manage™ (Sledgehammer) herbicide. It is a selective herbicide that only kills nutsedge and can be sprayed in close proximity to other perennials, shrubs and trees. It takes a few weeks for the plants to show decline, but Manage™ kills the whole plant including the runners and tubers. I have used Roundup as a control, but it is a non-selective contact herbicide that kills the weeds it contacts.   

Nutsedges are often unwelcome competition for our more desirable plants. These “weeds” can be controlled by a healthy, actively growing landscape. Competition and vigorous plantings will push these plants aside. If you do find it in your landscape, remove it immediately. If you have larger areas, be persistent, over time, you will get the upper hand.  Be as unrelenting as the weeds.  As they say on the Red Green Show, “We are all in this together. I am pulling for you.”

Seven Lessons I Have Learned About Native Plants

Over the 26 years that I have been at the Arboretum, I have made my share of mistakes. Some examples include planting prairie dock in a formal garden design, starting a garden too fast, and/or not knowing my site.  I had book knowledge about horticulture, but I had not learned much about native plants.  Through trial and error – mostly error – I learned some hard lessons and even killed a few plants along the way.  I am still learning, but here are seven lessons I believe are essential for a successful prairie garden.

1. Perennial and annual weed control

I have made this mistake too often. In a rush to plant, I don’t get problem weeds like bindweed and Bermudagrass under control before planting.  I am still fighting this issue to this day in some of these landscape settings. However, when I take the time to properly eradicate these weeds, the overall long-term success of the garden increases and the work to maintain it decreases. A little work at the beginning will save you many headaches down the road.

Bindweed

2. Plants should match your site.

This is the most important principle to follow in developing a successful landscape. Take a critical look at the area you want to landscape with native plants. Is it sunny?  It is shaded for part of the day? What type of soil do you have? Is there a microclimate? Is it exposed to wind? All these factors will guide you as you select plants for your site. This step requires some research and time as you familiarize yourself with the qualities and environmental needs of native plants.

Spiderwort (purple), coreopsis (yellow) and penstemon (white) in spring bloom

3. Succession of Bloom

There are no Wave Petunias in the prairie. If you visit a prairie landscape like the Konza Prairie every two to three weeks throughout the year, you will observe plants beginning to bloom, in full bloom or going out of bloom.  That is how you need to design your native landscape. Include plants that bloom in every season of the year and then strategically add grasses for movement and texture in the winter months. Take time to acquaint yourself with the life cycles of wildflowers and grasses.

4. Plan your garden for all seasons of the year

This lesson took the longest to learn, because it meant becoming familiar with the complete life cycle of each native plant. I needed to learn all about them – their bloom times, soil conditions they need to thrive, mature height and what they look like when not blooming, including seedheads and forms. Most of these characteristics had to be experienced over several years.  That information is vital to planning and developing a prairie garden.

5. Be Patient

A prairie garden does not magically appear overnight. I know this goes counter to our “instant everything” culture, but prairie plants don’t work that way. It takes time for those transplants or seedlings to develop root systems that will sustain them during the dry periods of the year. I remember visiting a prairie reconstruction in Wisconsin several years ago. It had been established from seed 20 years earlier and the prairie manager said it was just then really maturing into a true prairie. I have found that if you are patient, you will be rewarded by beautiful, strong and adapted native plants.

Graphic from Grow Native!

6. Start Small

Planting too much too soon – I have made this mistake many times. My eyes get bigger than I can manage. I like too many of these native plants and rather than working at a project in stages, I plant the whole area. I then spend the rest of the summer maintaining a planting that is too big for the time I can give it. It has a tendency to get out of hand in a hurry if I don’t keep up with it on at least a weekly basis. Plant an area that you can handle with your schedule.

7. Remember Why!

Most times we create something for our own enjoyment. A properly designed native garden can be very attractive to you aesthetically. What we often forget, but are quickly reminded of, is that native plants attract many different pollinators and other wildlife to our landscapes. If you plant them they will come.

Pollinators and wildflowers have a symbiotic relationship. Pollinators seek out the wildflowers they need and utilize them throughout the year. Monarch populations are declining. They need milkweed, and since we have milkweed in the Arboretum, they show up. Also, just like the monarchs, songbird populations are declining. They need prairie habitat for survival along with wildflower seeds to feed overwintering birds.

Obviously I have not figured everything out. Learn from my mistakes and maybe a few of your own. Gardening is not an exact science. What works for you may not work for me. Your site may be totally different from mine. The key is to keep learning. Try plants you believe will work in your landscape.

Besides learning lessons the hard way remember to connect with your WHY! The “WHY we do something” gets lost in the tasks of creating something new. I need to be reminded “WHY” from time to time to reset my focus. We each have our own unique perspective and motivation, but reconnecting with your “WHY” will move you ever closer to your native plant gardening goals.

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

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)