Keystone Natives for the Food Web

Posted on March 15, 2023 by Scott Vogt

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.

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.

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.

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

Posted on March 1, 2023 by Scott Vogt

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

Posted on February 17, 2023 by Scott Vogt

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.

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 Plantin g on our website.

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.*

Songs of the Solstice

Posted on December 21, 2022 by Katie Schmidt

When the weather is cold and the days are short, I just want to curl up on the couch and rest. And according to prairie plants, that’s exactly what I should be doing! As much as it pains us to see our favorite plants dry up and freeze in the fall, cold weather is an essential pause in the growth cycle for some plant species. Dormancy, vernalization, and cycles of freezing and thawing are an important part of their development.

A winter sunset dips below the horizon behind a bur oak tree and a snowy landscape. — *Photo by Gerry Epp*

Baby It’s Cold Outside

Contrary to how we feel about it, cold weather is a very good thing for plants in our region. In fact, there are many species of plants that cannot bloom without a prolonged cold period. Apple trees cannot form proper buds without 500 to 1,000 “chilling hours”. Tulips will not bloom without 12 to 16 weeks of cold soil temperatures. And even the historically finicky peach tree will not set fruit without a proper cold spell during the winter months. This cold period for plants is called ‘vernalization’. It all has to do with needing some rest — after a strenuous growing season, many plants use the signal of dark days and cold temperatures to go into their dormant phase, an energy-saving adaptation that allows them to jump back into full blossom in the spring. Why fight the harsh winter conditions when you can just sleep through it?

On Dormancy, or Rest Ye Merry Gentle(Plants)

Dormancy is not death, it is more like a long, deep sleep. In preparation for winter, plants stop actively growing and begin to transport their sugar reserves into their roots. This means the foliage may look shriveled and dried, but the roots are more alive than ever, packed with energy to get through the winter. When they go dormant, all the internal chemical processes of the plant slow down. Isn’t that good advice for us too? Slow down, give up trying to keep up all those lush, green appearances and just focus on your roots and energy reserves! Remember to give your plants a bit of water of the winter if things get abnormally dry; they are resting, but still need moisture to stay alive until spring!

The dormant trees of the Arboretum take the spotlight during our Prairie Lights event. The lights accentuate their form and help us to appreciate them even in the off season. Photo by Amy Sharp Photography.

Let It Snow

Native prairie seeds are especially in need of cold, moist winters. These seeds have incredibly hard seed coats, called testas. The outer shell of the seed is hard for many reasons: to protect it from the elements, to prevent it from germinating too soon when conditions are unfavorable, or to survive the inside of a stomach once it is eaten and, – *ahem* – expelled. But this hard seed coat does finally break open after many freezes and thaws in a Kansas winter. Moisture works its way into the seed and helps the process along. Without deep cold, seeds would not germinate as well or at the correct time.

*Seeds take many shapes and forms. Line drawing by Lorna Harder, can be found on our “Prairie Restoration” informational sign on the Arb grounds.*

Winter can be a beautiful season if you know where to look. Prairie plants provide interesting textures and colors even through the darkest days of December and January. And more than being aesthetically pleasing, leaving gardens standing through winter provides the necessary habitat and shelter for wildlife to survive cold temperatures. As you enjoy your own kind of dormancy this winter solstice, I hope you find some comfort in the natural cycles of waking and rest happening all around you!

Leave The Leaves

Posted on November 17, 2022 by Katie Schmidt

Leaves are everywhere this time of year, and for good reason! Leaves have an important role in the ecosystem. Trees and the organisms living in and below them have evolved for millions of years together, working in sync to create vegetation and break it down in an efficient cycle. But most Americans don’t realize this, quickly raking the leaves away as soon as they fall on our precious lawns. Well, here are some facts that might change your mind and urge you to leave that rake in the garage!

*The leaves of ‘October Glory’ maple are beautiful but my do they fall everywhere!*

For the Love of Lawn

Most people rake leaves out of concern for their lawns. Rightly so, as a thick layer can damage turf grass. Leaves staying wet too long causes snow mold, and without enough airflow even grass smothering, leaving bald patches next spring. But a light layer of leaves shouldn’t be cause for alarm – remember, a few leaves here and there will feed the lawn the nutrients it needs. You may consider using a leaf blower to thin them out if they are piled too high in some areas, allowing the turf to breathe through the winter. And when you think about it, if your non-native turf grass is so fragile and takes so much special care to grow well outside it’s natural environment…*maybe the problem is the grass, not the leaves?

*Our obsession with a 1950’s American Dream Lawn (which actually harkens back to medieval castle-dwelling elitism) is a problem; its a multi-billion dollar industry that relies heavily on chemical inputs, replaces native habitat, and sucks up millions of gallons of drinkable freshwater, but produces no useful food crop. Ready to ditch that old fashioned thinking and consider downsizing your traditional lawn space? More info here, here and here on alternatives.

Oh Leaf Me a Home

Leaves are home to lots of overwintering insects. We may not notice them, but these tiny friends are there, clinging to the underside of leaves and crawling into the leaf piles that collect in garden beds. While the well known and well loved Monarch butterfly migrates, most of our native insects do not! They desperately need these natural places to hid in winter, often as an egg, chrysalis, or hibernating as an adult. Many gardeners work hard to support declining insect populations all summer, only to ruin all their hard work in the fall when they take all their leaves to the curb.

*Many butterflies and moths depend on leaf litter for shelter.*

Paper or Plastic

Too many folks spend their beautiful fall days bagging up leaves and sending them away. This creates a lot of plastic waste. Not only are we sending enormous amounts of plastic to the landfill, all the insects, eggs, and larvae already on those leaves will die inside the bag, never to take their place in the ecosystem! The nutrients in that foliage will not return to the soil, and instead stay trapped for hundreds of years in their plastic prison.

Free those leaves, folks! Let them decay and feed the soil microbiome. If you must haul them away, load them onto a tarp for transport, or opt for paper bags that can be composted with the leaves.

*Our student employee Rachel shows the size of a typical paper yard waste bag.*

I love a lush, green lawn as much as the next person, but we can all aim to achieve a useable lawn space while also being kind to the environment. If you have too many leaves in one area, spread them out, move them to your garden as free mulch, or start a neighborhood leaf compost pile. If you must haul them away, stick to compostable or reusable containers and consider taking them to a city compost area or even your local Arboretum! Doing your part to help the environment, in this case, means less work for once. So stay inside and watch that football game, the leaves in the yard can wait.

Final update: Buffalograss Experiment

Posted on November 2, 2022 by Scott Vogt

As the growing season comes to a close, I like to take account of the garden before it goes completely dormant. Certainly, this has been a challenging year in the garden. The plants I installed last May in front of my house are still alive, but it took daily watering through the summer to keep them going. It is safe to say that without regular attention and water, I would have lost all of those tiny plants. I am still watering them twice a week.

**Aster oblongifolius** ‘Raydon’s Favorite’

Here at the Arboretum, I find the resiliency of the prairie and certain display beds encouraging. While they are under stress, these plants adapt well to the high and lows along with wet and dry conditions. I have also been monitoring the buffalograss experiment I started over two years ago in the fall of 2020.

Our Experiment

As a reminder, in the fall of 2020, we tried a new seeding technique with buffalograss. We had our area prepared and ready for planting. That November, we seeded the area with annual ryegrass and buffalograss seed. The ryegrass is a cool season grass that prefers cooler weather. Once it germinated, it held the soil through the winter while the buffalograss seed naturally planted itself with the freezing and thawing of the soil. The round buffalograss seeds did not germinate because soil temperatures were below 60 degrees.

*Annual ryegrass mowed for the second time in the spring of 2021*

The Next Year

In the spring of 2021, the buffalograss seed germinated as the soil temperatures warmed. By May, the new seedlings had started to spread under the canopy of the ryegrass growing from the previous fall. As the temperatures warmed into the summer, the annual ryegrass faded since it is a cool season grass and the buffalograss became more prominent. By the end of the summer, new small clumps of buffalograss established, slowly spreading but healthy.

Since Germination

We mowed the annual ryegrass weekly that first year. It is important to keep the canopy open so the sun could warm the soil allowing the buffalograss seeds to continue to germinate. Buffalograss takes two to three weeks to germinate. The seeded annual ryegrass expired on its own with warmer summer temperatures. As the ryegrass died, the roots of the ryegrass continue to hold the soil as the buffalograss spread slowly the rest of the summer.

*Buffalograss clump will benefit from a pre-emergent herbicide application next spring.*

UPDATE: Analysis and what I would do differently

I would deem this buffalograss experiment a success. Honestly, I thought the buffalograss would spread more over the past year, but there are many clumps sprinkled throughout the area that are getting larger. The additional costs to purchase annual ryegrass seed are offset by the time and water saved compared to the traditional seeding method.

We will be putting down a pre-emergent next spring to keep the crabgrass and other summer annuals from germinating. Some pre-emergent herbicides safe for use in buffalograss are Barricade (prodiamine), Pendulum Aquacap (pendimethalin), Dimension (dithiopyr), and Specticle (indaziflam). There are some nice clumps of buffalograss, but they are hampered by intense weed competition. Weed competition was aided by tillage (soil disturbance), and the backfill soil added along the new sidewalk, which was full of weed seeds.

I would only use this seeding method on smaller areas of less than 1000 sq/ft. In my opinion, larger areas that are properly prepared should be planted from seed in the summer before August 15th. We seeded a larger area this past summer to buffalograss using the traditional method and had good germination and coverage. Here are some other things I would do differently:

Reduce the seeding rate of the annual ryegrass: Though the packaging recommends that you plant 3-4 lbs./1000 sq. ft. I would only seed 2-3 lbs./1000 sq. ft. The seeds will still germinate to hold the soil through the winter, but not be so dense that they shade out the buffalograss seeds in the spring.

Plant buffalograss seed first and slightly cover it: I had some buffalograss seed float off the soil as I established the annual ryegrass seed last fall.

Start the process earlier in the fall after the first freeze (October 15): It is better to establish annual ryegrass with slightly warmer temperatures, but not so warm that the buffalograss seed germinates.

Fall Planting of Native Grasses

Posted on September 14, 2022 by Scott Vogt

One of the questions we get at every fall plant sale is “can we plant these grasses now?” The answer is “yes, we encourage fall planting of native grasses”, but with some caveats.

Here are a few questions to answer before you jump into planting native grasses this fall such as:

Is your area ready to plant now?
Are you able to water it daily for the first few weeks and into the winter if needed?
Do you have the right location for these grasses?

I tend to err on the side of caution for late fall planting because losses can be incurred. However, you can be successful if you follow a few guidelines.

Around South Central Kansas, our first average frost is October 15. Typically, we plant native grasses as soon as possible in late August or early September to give them more time in the ground to get established. As a general rule, it is best to have native grasses in the ground three to four weeks prior to the first fall frost. This will give the plant time to get established with roots fully attached to the soil to absorb water and nutrients through winter.

This attachment by the roots to the soil is so important because it keeps the grass from being heaved out of the ground. The natural freezing and thawing of the soil during the winter can be extremely strong, pushing partially established plants out of the ground and breaking roots, which results in desiccation and death of the plant. Properly establishing plants before winter will protect them from this force.

Another factor to successfully transplanting grasses in the fall is soil temperature. Typically, native grasses will continue to grow (root) with soil temperature above 60 degrees. So installing grass plugs in August through mid-September is a proven strategy, because soil temperatures remain optimum until after the first frost.

We have had success with planting native grass in the fall. The most obvious benefit of this approach is that the grasses will break dormancy next spring fully established and ready to grow. As temperatures warm they will have a head start over early spring plantings.

Note: It is always good practice to check the soil around fall planted perennials (including grasses), trees and shrubs during the winter for moisture. If the top one to two inches of soil is dry, it is good to give them a light watering. Remember, they are dormant so they don’t need much.

Warm Season Grasses for fall planting:

Big Bluestem Andropogon gerardii and cultivars
Sideoats Grama Bouteloua curtipendula
Blue Grama Bouteloua gracilis
River oats Chasmanthium latifolium
Pink Muhly Grass Muhlenbergia reverchonii
Mexican Feather Grass Nassella tenuissima
Switchgrass Panicum virgatum and cultivars
Little Bluestem Schizachyrium scoparium and cultivars
Indiangrass Sorghastrum nutans
Prairie dropseed Sporobolus heterolepis

Cool Season Sedges and Grasses for fall planting:

Appalachian Sedge Carex appalachica
Bicknell’s Sedge Carex bicknelli
Pennsylvania Sedge Carex pensylvanica
Rosy Sedge Carex rosea
Texas Sedge Carex texensis
Bottlebrush grass Elymus hystrix

*Mexican Feather grass planted in the fall of 2020*

Saturated Soils and Wilting Plants

Posted on May 11, 2022 by Scott Vogt

This year we have been facing many environmental challenges from wind, drought, torrential rain for a lucky few, and now soaring temperatures. Nobody said gardening in Kansas would be easy. One of the more common problems we see in spring is wilting plants, especially those that are newly transplanted. This is true after the big rains last week and now the heat of this week. The new gardener may wonder – “what’s wrong with my plants?”

Saturated Soils

The heavy rain has resulted in saturated soil. Plants need water, but standing water for hours or even days depletes the soil of valuable oxygen. The roots need oxygen present in the soil, but as voids are filled with water, the oxygen is removed and root systems can become damaged. The fine root hairs die from lack of oxygen. These fine hair roots are vital for water and nutrient uptake by the plant. Whether it is a perennial or vegetable crop like tomatoes, the plants wilt because the uptake of water has been interrupted.

Will the wilting plants recover?

A number of factors affect the plant’s ability to overcome a flooding episode. How long the plants were flooded, drainage away from the root system, type of soil, type of plants (think about their natural habitat: some plants appreciate wet soils while other don’t), and how long the plant has been established. A newly established plant will be more affected than a mature plant.

Many vegetables crops are sensitive to flooding or saturated soils, but if the soil dries out quickly they will usually recover on their own with no help from us. Heavily mulched plants with more than two to three inches of mulch tend to stay wet too long for many perennials. If you see this wilting happening, check soil moisture. The mulch is not allowing the soil to dry out and may be damaging the roots. Rake back the mulch for a few days to encourage the soil to dry out.

If the soil stinks, then it has transitioned into an anaerobic state and everything is killed in the soil, including microbes and roots. Not a good situation. At this point it is very difficult to bring a plant back, because it is too badly damaged. Native plants generally appreciate good drainage. Root rot or crown rot are two of the most common problems, because the soil stays wet too long. As an example, narrow-leaf coneflower (Echinacea angustifolia) grows on rocky hillsides with keen drainage and no standing water. Planting one of these coneflowers in a flat garden with heavy clay soils is a recipe for disaster.

This time of year, gardeners should also be on the lookout for increased incidences of diseases such as early blight and powdery mildew. Humidity and excess moisture can quickly damage plants with these diseases, too.

Yellow Leaves

*Echinacea turning yellow from too much water*

Yellowing foliage can also be a problem after a heavy rain event. This is a visual indicator of compromised roots, but also the leaching out of nitrogen in the soil. Nitrogen is mobile in the soil and moves downward away from roots with moisture. An application of slow-release fertilizer like Osmocote or a liquid fertilizer will green the plant back up over time.

I only recommend fertilizing fully established perennials, i.e. plants you put into the ground last year. Fertilizing newly planted perennials will cause excess top growth without a sustaining root system. With native wildflowers and grasses, it generally takes three to five years to develop a sustaining root system.

To avoid these problems, it is critical to match plants to your site. Good drainage and keeping moisture away from the crowns of the plants will keep your plants healthy too. Don’t put too much mulch around your plants, especially the main stem. Plant your garden densely and let the plants be the mulch.

If you do mulch your garden, only put enough to just cover the soil. Usually one to two inches is enough. Allow the plants to develop roots that tap into the moisture and nutrients. We need the spring rains, but sometimes we can get too much for our newer perennials.

The first year: Getting native plants established

Posted on April 26, 2022 by Scott Vogt

Originally published on May 27, 2020

The prairie communities we see are diverse and complex. Plants, intricately woven together, crowd out weeds and harmoniously coexist. When you look at a prairie, you only see about 1/3 of the plant. The root systems that sustain these native plants make up the remainder, because they reach deep into the soil. The first year is so critical to the whole process of getting native plants established. Developing these root systems properly is vitally important and the establishment period takes time. Here are a few steps I take to get my new native plants started.

Planting

I like to lay out the entire area by placing the plants where they are supposed to be planted. This does a couple things: first, it helps with proper spacing of the plants and second, it helps to visualize the final outcome. Think about mature size, rather than what the plants looks like in its infant state.

Now that we have the plants laid out, we can start putting them in the soil. It is critical to not plant them too deep. In our heavy clay soils, it is best to plant them level or slightly higher (1/8 to ¼ inch) than the soil line, especially in heavier clay soil. This keeps the crown drier, which is important for disease control. Over time, these natives will develop at the depth they prefer to grow in.

Watering

Now that the plants are in the ground, they need frequent watering until they get established. Even drought-tolerant plants need to be watered daily until they begin to root and connect with the soil around them. Keep in mind that improper watering is the most common reason for plant loss during the establishment period.

For me, I water each new area by hand rather than with a sprinkler. It helps me control the amount of water each plant receives and directs it to the intended plant. I water every day for the first two weeks depending on the weather. After that first two weeks, you should start to see new growth.

For the next few weeks, I water every other day or every third day as needed, monitoring the planting each day for signs of stress/wilting.

Even after this month long process of establishment, each plant must be monitored and watered through the following summer, fall, winter and spring. Native plants are not established until the second summer.

Remember, it takes a few years for those roots to fully develop. If your plants are properly sited, you will not need to water much after the first full year. However, if you must water your area during a dry period, natives will appreciate deep and infrequent watering.

*Using a watering wand to direct water on to new plants*

Don’t Fertilize

People ask me all the time about fertilizing native plants. As a general rule, I don’t fertilize our native plants especially during that first year. Think about those small plants in the ground and what will happen to them if they are fertilized. They will have tremendous top growth that is not sustainable by the small root system. This will put the plant under stress and slow its progress.

Natives are resilient and adaptive. The deep roots most often will find the nutrients and moisture each plant needs.

Mulch

In the book Planting in a Post-Wild World: Designing Plant Communities for Resilient Landscapes, Thomas Rainer and Claudia West develop the ideas of layering plants. There are usually at least three distinct layers of plants: the upper layer filled with taller structural plants used to frame and punctuate the landscape, the middle layer filled with ornamental flowering plants and the ground level that weaves the other layers together and shades the soil, which controls weeds.

These layers mimic natural plant communities and each layer is important for the health of the plants. A collection of plants living in community can be extremely drought tolerant and water-thrifty.

If you decide to mulch your display beds initially, only place one to two inches of mulch down and keep it away from the stems. This is fine as the beds are first established. As they mature, less mulch is needed because, with the right care, the plants become the mulch. Something to think about is whether you have seen mulch in the prairie? No, the plants eventually co-mingle and intertwine to push out weeds.

Creating a native landscape takes time. With each new plant established comes an expectation of a brighter future. Often, we garden and landscape our yards with the anticipation of what we will get rather than what we are giving back. By adding native plants to our gardens, we will help make our gardens not only beautiful, but also productive and full of life.

Pine Diseases Changing Landscapes Forever

Posted on March 30, 2022 by Scott Vogt

The Arboretum continues to change. If you visited the Arboretum in the early years, you would have seen many different types of pine trees and other evergreens planted in groves. These pine trees initially flourished, even though they are not native to Kansas. However, over the past 20 years, the Arboretum has lost many of those original pine trees.

This is not an isolated problem. Whole shelterbelts, specimen trees and screens have been decimated by diseases exclusive to pines. What are the most common pine diseases and what can be done to control their spread? That is a question I’m often asked and there are no easy answers. I do suggest Kansas State Extension and online resources for more information.

Pine Wilt

Pine Wilt threatens to remove several pines permanently from the landscape. Discovered in Missouri in 1979, pine wilt is most serious on Scotch Pines but can infect Austrian and White Pines. Since that initial report, it has continued to move westward and has completely decimated all of the Scotch pines in the Arboretum.

Symptoms for Pine Wilt usually appear from August through December and cause the trees to wilt and die rapidly in a month or two. Trees may survive for more than one year but the result is always fatal. The needles turn from bluish-gray to yellow/brown and remain attached to the tree.

Several organisms play a role in the death of a tree. The pinewood nematode is transmitted from pine to pine by a bark beetle, the pine sawyer. Once inside the trunk, the microscopic worms feed on the blue stained fungi that live in the wood but also on the living plant cells surrounding the resin canals and water-conducting passages, essentially choking the tree. There are no highly effective management tactics. Dead pines should be promptly cut and destroyed before warm weather of spring. If this is not done, beetles can continue to emerge from the logs and infect more trees.

*Austrian Pine dead from disease that will be removed this spring in the Arboretum*

Other Pine Diseases

Foliar diseases such as Sphaeropsis Tip Blight (STB), Dothistroma Neddle Blight (DNB), and Brown Spot of Pines (BSoP) are caused by types of fungi that can infect both the new and old growth. Some of the species affected by these diseases include Austrian, Mugo, Scots, and Ponderosa Pines. The symptoms of STB appear on the current year’s shoots. As the new shoots emerge in the spring, they are susceptible to infection by the fungus. Any damaged area provides the spores a way into the tree. The spores are dispersed by water and require high humidity for germination and penetration of the host tissue. Both DNB and BSoP cause spotting of the needles and eventually premature defoliation. Transmission is again by water and moisture. In a year with many spring rains, the moisture can spread the spores like wildfire and many treatments are needed to keep them in check.

Treatment Options

These three foliar diseases can be treated with multiple applications of copper fungicides and Bordeaux mixtures in the spring and early summer. Treatments are costly and high pressure equipment is needed to project the spray to the top of the trees. It has been my experience that control of these diseases is difficult. Spray timing is critical, densely planted trees are highly susceptible, and infection occurs during excessive rainfall. Thinning trees and removing dead or diseased branches will prolong the life of the tree, but the best defense is to keep the trees healthy by providing adequate moisture and fertility.

Diversity is the Key

One of the key lessons we have learned from this experience is that diversity is vital to a successful landscape. Whether pine trees, deciduous tree, perennials or shrubs, don’t put all your eggs in one basket. Establish a variety of plants adapted to your landscape rather than just one or two species. The truth is that you can do everything right and still lose an evergreen tree. Replant with a diverse variety of species so your whole landscape will not be open to widespread devastation again. There will be other diseases that come, but diversity will give you the edge.

Other Evergreens

New evergreen species are being trialed for adaptability in Kansas, but at this time there are not many viable alternatives other than our eastern red cedar with cultivars such as ‘Taylor’ and ‘Canaertii’. Southwestern White Pine (Pinus strobiformis), Arizona Cypress (Cupresses arizonica), Black Hills Spruce (Picea glauca var. densata) and Pinyon Pine (Pinus edulis) are also viable options. Full descriptions of these trees can be researched on the internet or you can come to the Arboretum and view them in person.

Pines like Ponderosa (Pinus ponderosa), Austrian (Pinus nigra) and Scotch (Pinus sylvestris) have been taken off the recommended tree list because they are so prone to disease. I would highly encourage you to visit the Kansas Forestry Service website at www.kansasforests.org . Once there, choose your region to view a full list of recommended trees for your area along with other informative publications.