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.
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.
Last Monday’s spring equinox marks an interesting time in our calendar. We’re nearly three months into 2023, but following the seasonal calendar, a new year is just about to begin.
The spring equinox is a time of paradox – spring is both here and not yet here. Each day, as the Earth turns in its relationship to the sun, lengthening our time of daylight in the Northern Hemisphere and warming the soil, plants, birds, insects, mammals and amphibians all respond to nature’s alarm clock. Despite cold snaps and high winds, creatures up and down the food chain begin to stir.
While we may grumble of tree pollen, cold snaps and high winds, something inside of is also buoyed by the innate sense of hope in this slow turning of the seasons. One of our long-time members and neighbors recently shared a series of poems with us, entitled “Arboretum Seasons”, which she wrote in response to her daily walks around the pond during the pandemic. Here are her impressions of spring, reminding us of everything we have yet to enjoy in the coming spring months.
The Arboretum wakens with the music, fragrance
and rainbow hues of Spring
The “Chee-chee-chee” of scarlet Cardinal
the warble of black and orange Oriole
the Robin hunting worms on the lawn
the soft cooing of Doves
and the “Konkaree” of Red-wing Blackbirds
clinging to swaying Cattails lure us.
The fragrant Lilac, the Crocus and Columbine welcome us;
also the Evening Primrose that wilts in the sun.
Delicate green Birch leaves tremble in the breeze.
Vivid pink of Crabapple and pale pink and white
Apple blossoms border the path.
Forsythia adds its gold as we circle the lake.
A cacophony of Spring Peepers hushes as we pass.
Shy Violets peep from the grass beneath towering Cypress
and the Weeping Willow kisses the lake.
As they swim across the lake, Mama and Papa Goose
guard fluffy yellow goslings
from vicious Snapping Turtles.
The perfume of Mock Orange, Daffodil and Narcissus lingers with us as we leave
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.
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.
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.
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.
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.
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.
When a new plant is introduced into the market, it is more than just a fancy name. Plant breeders work for years, sometimes decades, to perfect and patent a distinct new plant variety. Sometimes this is the work of hybridization, complicated gene editing or human-aided crosspollination. But other times it starts by finding an interesting plant in the wild that varies from its normal phenotype and reproducing it reliably in trials to get ready for the mass market. Either way, after all that work, it is exciting to see the results!
Here are two new grass varieties available at our spring FloraKansas event, both the result of finding great natural specimens growing wild and capitalizing on their landscape-worthy traits.
Sorghastrum nutans ‘Golden Sunset’
I’ll admit that Indiangrass, also known as yellow prairie grass, is not my favorite of our native species. It is always flopping over and spreading everywhere. I don’t care for its sloppy habit. But ‘Golden Sunset’ might change my mind! Selected at the University of Minnesota and in development for 15 years, this grass is known for its upright habit and early flowering. That means more time to enjoy the bright yellow feather-like plumes, and they won’t fall over in the strong Kansas wind! Great for creating a screen or living fence, or as an accent in the back of the garden. Use Sorghastrum ‘Golden Sunset’ in place of non-native and invasive Pampas grass. Sorghastrum serves as a host plant for the pepper-and-salt skipper butterfly.
Grass height: 3 ft Grass with blooms: 6 ft Plumes can be up to 12 inches long!
Andropogon ‘Karls Cousin’
Big bluestem (Andropogon gerardii) is an important species in the tall grass prairie ecosystem. Beyond providing an incredible amount of biomass for grazers, birds and insects, they are also well loved in the urban and residential landscape. ‘Karl’s Cousin’ is a selection found by breeder Dave MacKenzie growing on the side of the road. It was distinct and eye-catching, and after taking may divisions and many years in the trial garden, ‘Karl’s Cousin’ was named as a new variety of Andropogon. It’s much more upright than the species, with good color and strong stems and can be used as a replacement in some situations for ‘Karl Foerster’ grass, a non-native cool season ornamental grass. Where the straight species big bluestem might be too large or floppy for a city garden, this variety makes it possible to include in even small spaces.
Grass height: 4 ft Grass with bloom: 7 ft Great fall color!
Grass for Every Place
We have been planting and selling native grasses here for many years. We definitely have our favorites, like ‘Northwind’ Panicum and ‘Twilight Zone’ Schizachyrium. But there are hundreds of great grass species out there to fit any landscape. Dry, rocky soil? Try a western Kansas species like Bouteloua gracillis. Need a tall and fast growing living fence? ‘Dallas Blues’ switchgrass might be right for you. And if you have too much shade for traditional prairie grasses, consider adding sedges to your garden. While not technically in the grass family, these plants add grassy texture but can handle conditions from dry shade to full sun bogs. Keep your eye on our FloraKansas page to get the Native Plant Guide as soon as we update it for 2023, so you will know what species we have available this year.
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.
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.
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.
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.
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.