Old Wood, New Buds: A Pruning Guide

Posted on November 29, 2017 by Katie Schmidt

Though true winter approaches, there are still a few warm, sunny days ahead to be filled with raking leaves and garden clean-up. Here at the Arboretum we leave our perennial gardens uncut through the winter to create winter habitat and protect the soil, but just like you, we are plenty busy piling up leaves and preparing our Christmas decorations. If the weather is truly obliging, you may even be tempted to bust out your pruning shears and neaten up your trees and shrubs. Less work waiting for you in spring, right? But be warned, overzealous and untimely snipping could cost you! Below is a seasonal summary of pruning information compiled from the four corners of the web, along with a botany primer on buds and the old wood/new wood conundrum.

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

When to Prune What

The truth is, most plants don’t need much pruning. Pruning should never aim to distort the shrubs natural figure, only enhance its shape and thin branches to ward off disease and breakage. Gardeners often ask me when to prune their (insert flowing shrub here) for the best bloom – the truth is, I don’t have all that knowledge locked in my brain! I often whip out my phone to research the specific plant and find out if it blooms on new growth or last years wood. If a plant flowers on last years wood, pruning in winter or spring means you will cut off all the already produced dormant flower buds and greatly reduce or eliminate the coming year’s bloom. Here is a run-down of when to give some common landscape plants a haircut.

Crypemyrtle (Lagerstroemia) – blooms on new growth, prune in late winter before it leafs out to get a good view of the form

Lilac (Syringa) – blooms on last years wood, prune immediately after flowers have faded, before next years buds form.

Butterfly bush (Buddleia) – blooms on new wood, so prune/shape in early spring

Buttonbush (Cephalanthus) – blooms appear on new wood, prune in late winter/early spring

Hydrangeas – very tricky, as not all grow the same! Cut back H. paniculata and H. arborescens in late winter; they bloom on new wood. H. macrophylla and H. quercifolia bloom on last years wood and can only be trimmed immediately after their blooms fade.

**A great in-depth guide to evergreen pruning can be found HERE from Morton Arboretum. But if you just want the quick dirt…

Pines – early spring just as new growth begins, but not before.

Spruces, Firs – early spring before new growth begins

Juniper, Arborvitae, Yew – late winter or early spring before new growth begins

Yews (Taxus) can generate growth on new or old wood, so they can tolerate heavy pruning and shaping in the early spring, then again in June if needed. Photo By Philipp Guttmann (Own work) [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons

Know Before You Cut

Surgeons go through years of rigorous schooling before they make a single cut, so why don’t we spend a few minutes learning about buds and shoots before the amputations begin, eh?
A bud is an embryonic shoot just above where the leaf will form, or at the tip of a stem. There are lots of different types of buds: Terminal buds (primary growth point at top of stem), lateral buds (on sides of stem that produce leaves or flowers), dormant buds (asleep and waiting for spring, shhh!), and many more.

Buds can be classified by looks or location.
By Mariana Ruiz Villarreal LadyofHats [Public domain], via Wikimedia Commons

In light pruning, such as pinching or heading, cut just above the bud at a 45 degree angle. Lowes has a great guide on the 4 types of pruning, and a very helpful graphic seen below. A cut too far above or below the bud may result in die-back and withered stems.

This angle is optimal for encouraging grown and also hiding your cuts. Graphic from Lowes.com, https://www.lowes.com/projects/gardening-and-outdoor/prune-trees-and-shrubs/project

Cutting directly above the bud tells the plant to release hormones signalling the bud to break dormancy and sprout! Learning about the process of plant dormancy can ensure we aren’t wounding plants at vulnerable times, The Spruce has a great article on this here.

Research first, then cut carefully, friends!

HAPPY THANKSGIVING!

Posted on November 22, 2017 by Scott Vogt

We hope you have a great Thanksgiving as you celebrate the holiday with family and friends. We are most thankful for you and the opportunity to serve you. Your support in many different ways continue to help us grow. THANK YOU.

Janelle, Brad, Katie and Scott-The Dyck Arboretum of the Plains team.

Thank You to all the volunteers who helped us this past year. There are over 150 of you who have given of us your time and talents.

EPS Students-The next “Citizen Scientists” that will impact the world.

Baptisia ‘Purple Smoke’

Vernonia ‘Iron Butterfly’ with hawkmoth

A few Thanksgiving thoughts:

“I come from a family where gravy is considered a beverage.” Erma Bombeck

“Feeling gratitude and not expressing it is like wrapping a present and not giving it.” William Arthur Ward

“Vegetables are a must on a diet. I suggest carrot cake, zucchini bread and pumpkin pie.” Jim Davis

“I am grateful for what I am and have. My thanksgiving is perpetual.” Henry David Thoreau

LUMINARY WALK-Join us on Friday or Saturday, November 24, 25 or December 1 and 2 from 5:30-8 pm.

An Annual Dilemma

Posted on November 15, 2017 by Brad Guhr

A recent September Dyck Arboretum trip to Kansas City and the home of Lenora Larson spurred for me a dilemma regarding landscaping with non-native annual plants. I have typically spurned the use of annuals for reasons I’ll elaborate on more later. But Lenora makes a very compelling case for using more annuals in the home landscape.

“Best Butterfly Godmother Possible”

Lenora Larson is indeed a master gardener with a mastery of providing host and nectar plants for a great variety of insects. Her father was a botanist and her mother was a landscape designer, so she certainly has a lineage for creating interesting and beautiful gardens. She was a microbiologist before retiring; with a scientist’s curiosity, she keeps alive a keen interest in learning more about the natural world (especially plants and insects) around her. This passion was evident during her “Gardening for Butterflies” winter lecture talk at the Arboretum in March this year, and it was especially apparent as we toured the gardens around her home.

*Lenora Larson giving a tour of her garden*

Lenora hates planting and, therefore, smartly touts the use of long-lived perennials as well as self-sowing annuals. She is a hard-working gardener, and loves spending 6-8 hours per day weeding and mulching during the growing season. She breaks down by hand all the vegetation on site to keep around the seeds and insect eggs that will keep the cycles going next year. Lenora is an artist who has a genius eye for aesthetics, composition, texture and color. Not only are her gardens graced with “plant art”, but many permanent art installations of sculptures, trellises, paths, and walls are carefully and purposefully included as well. Her gardens are visually stunning.

To an ecologist’s eye, Lenora’s gardens are fascinating. The numbers of butterflies, moths, bees, flies, beetles, and insects in general were incredible and so interesting. She could recognize and identify practically every insect we saw and her stories extended to amphibians, reptiles, birds, mammals and more. Lenora’s planting formula is generally to plant about 50% native perennial host plants for hungry insect larvae, and then as many flowering nectar plants as possible (annuals included) for the adult insects. Thanks to the annuals, Lenora’s gardens feature flowers from April through November. Lenora is willing to use glyphosate (e.g., Roundup) herbicide carefully to keep her paths looking clean when needed, but as you might imagine, she is staunchly against the use of insecticides.

My Historical Context for the “Dilemma”

Allow me to give a bit of background on why landscaping with annuals even poses a dilemma for me.

I have been a bit of a snob in the past about planting only native perennial plants. With a fresh background in plant ecology and ecological restoration when I came to the Dyck Arboretum nearly 14 years ago, my focus was all about trying to mimic native plant communities while conducting prairie restorations, improving the ecology of my own back yard, and providing others with landscaping recommendations. This included not only the exclusive use of species with historic presence in south central Kansas, but trying to stick to local ecotype plants of those species as well whenever possible. Native annuals such as annual sunflower, and a couple of different ragweed species are important ecologically in their functions of holding soil and providing lots of seed food for wildlife. However, they generally aren’t appreciated in landscaping applications, because they are aggressive and/or aggravate allergies.

These “native only” ideas were fairly compatible with the mission and focus at Dyck Arboretum, which are firmly rooted in landscaping with native plants. In Central Kansas, that means using plants of the prairie. This approach is what sets us apart from other plant nurseries. It feeds our mission of education and stewardship, and it connects us to a sense of place by embracing historical plant communities important to our Kansas cultural and natural history.

But while this restrictive approach of “natives only” had its merits in designing, collecting seed, and planting our Prairie Window Project prairie restoration at the Arboretum, I quickly learned that this ivory tower mentality was not held by most other people. It also wasn’t a very sustainable approach for an organization engaging the general public on environmentally-responsible landscaping.

So, in addition to promoting use of native plants, our mission also embraces the use of adaptable perennials that may have originally grown elsewhere, but are still adapted to grow well in our soils and climate. Today, in a cosmopolitan world where information and biological organisms are shared easily around the globe, it seems impossible to take a natives only approach.

Using Annuals

One of the main reasons I’ve been biased against annuals for landscaping is their regular need for water. Annuals have shallow root systems compared to perennials. Dry, hot Kansas summers are not always conducive for growing annuals from places in the world with cooler and wetter climates.

Lenora Larson’s house sits next to a well-fed pond that she uses for her irrigation needs. Cosmos and zinnias have done well as part of our community garden vegetable plot, because we water them regularly. And we do enjoy the abundance of butterflies they attract throughout the summer. I’m just not sure if I want to commit the time and environmental/monetary costs to keeping annuals alive around my home too.

But in 2018, I have decided that I’m going to give this annuals approach a try to supplement my native perennial gardens. I plan to follow Lenora’s succinct 3-page guide, in which she summarizes her gardening approach and offers her favorite self-sowing annual plant species choices with descriptions of each. For many of these species she recommends, I’ve searched online and provided photos of the flowers below. Maybe you are already implementing many of Lenora’s annual species suggestions and seeing the rewards. If not, consider joining me!

*Zinnia angustifolia – Profusion Orange*

Lenora’s Self Sowing Annuals Guide

Photo Credits

What Are The Benefits of Hedges?

Posted on November 8, 2017 by Scott Vogt

As you design your landscape, one of the first questions to consider is the need for screens and hedges. Do you need to block an undesirable vista or define an area? Do you need to line a path or camouflage a utility? Hedges help outline boundaries. Instead of a rigid wall or fence built with wood or brick, why not create a living wall or screen using a variety of plants? A living fence will provide much needed wildlife habitat while slowing the wind, improving air and water quality and beautifying the landscape.

Here is a mixed planting with taller shrubs/trees in the background.

When I think of hedges, my mind automatically pictures shrubs neatly trimmed and closely spaced, but it can be so much more diverse. A non-traditional hedge can be created with many different types of plants. This approach creates layers of varying heights that naturally block the view or envelope the space. The key is matching the plants to your site and grouping plants in informal clusters rather than in predictable rows. Hedges can be an essential element in a sustainable landscape design.

Blackhaw viburnum and Dallas Blues Switchgrass

Diversity is the key to the longevity and success of any hedge. If you drive through the country, you see screens and windbreaks that were planted with only three to four species in rows, and have, over time, been devastated by decay and disease. Who knew that pine wilt or tip blight would kill so many pine trees 50 years ago? A diverse selection of evergreens, deciduous trees, understory trees, and shrubs, grouped together in irregular patterns, would allow the removal of a dead or dying plant without compromising the whole planting. This large scale example can be incorporated into a smaller back yard planting. By using a wide variety of plants, you will avoid this lack of diversity pitfall.

Buffer planting along a driveway.

Typically, hedges are made up of evergreens or shrubs, but even wildflowers and grasses can be mixed together to produce an attractive screen. Tall grasses such as switchgrass and big bluestem, along with wildflowers like New England aster and culvers root, become intertwined and dense, creating an informal hedge that provides valuable habitat and season-long interest. Intermingling shrubs with blooms and interesting foliage contributes additional food, nectar and shelter. The varying heights and undulating forms boosts the wildlife attraction and overall beauty of the planting. In instances where space is an issue, again, avoid planting in rows. Instead, plant in groups of three or five and add as many different plants as possible.

Prairie Dropseed, Giant Black-eyed Susan and yellow coneflower

Here are some examples of plants we recommend for hedges:

Evergreen choices

Eastern red cedar (Juniperis virginiana), ‘Caneartii’ or “Taylor’, Arizona Cypress, Southwestern White Pine, and Leatherleaf Viburnum

Native grass recommendations

Switchgrass-Panicum ‘Dallas Blues’, Panicum ‘Northwind’, Indiangrass-Sorghastrum nutans, Big Bluestem -Andropogon gerardii

Wildflower recommendations

New England aster, culvers root, penstemon, bluestar, bee balm, black-eyed susan, blazing star, beardtongue, coneflowers, goldenrod, and blue sage

In my own yard, I have a cedar fence to keep my dogs from escaping. However, I have softened the fence with an assortment of flowering shrubs and mixed prairie plantings in the front of it. These buffer areas are much more appealing than the stark vertical fence. The benefits of a living screen or hedge in the landscape are many. These natural plantings provide privacy, protection against wind, reduce noise, enhance energy conservation, create wildlife habitat, increase species diversity in your neighborhood, beautify the landscape and screen unsightly elements.

Hedges can do so much to improve your landscape. Why not take a second look at some of these areas in your own yard? A few additions could make a tremendous difference.

Additional resources

Native Shrub List

Native Plant Guide

Are Bulbs Good for Pollinators?

Posted on November 1, 2017 by Katie Schmidt

My volunteers and I have been spending many hours this fall planting daffodils and tulips around the Arboretum grounds. All told, we will have nearly 800 new blooming bulbs coming up next spring, down a bit from the 1000 we planted last year.

One afternoon my colleague Brad Guhr posed an important question:
“Are bulbs useful to spring pollinators?”

We all love the aesthetics of fat yellow daffodils and spritely crocus, but I had never considered whether they served an ecological purpose. Supposing (incorrectly) that most bulbs I order are native to the Netherlands, what good would they be to our local pollinator population?
I have now been down the rabbit hole of research and will summarize here how bulbs affect pollinators, which bulbs attract them and proper bulb planting technique.

Tulip humilis (aucheriana) is a wild-type tulip that does well in gardens and meadows alike.
By Bernd Haynold – selbst fotografiert – own picture, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4767022

Bulbs and Bugs

Long before people started admiring their blooms, most of our favorite bulb flowers were being visited by pollinators. Such is not the case for today: modern hybrids selected for the biggest bloom and brightest color sometimes become less useful to pollinators. Flowers that have been distorted too far from their original form may have less nectar or be entirely sterile, rendering them useless as a food source. Hybridization can also sacrifice the flower’s strong scent, leaving aroma-sensing pollinators (like nocturnal moths) lost without lunch. As humans try to improve flowers for our own eye, we inadvertently disrupt their role in nature. Insects and flowers have an important relationship directly related to the flower’s form. If it changes drastically, certain insects may no longer be able to reach the nectar. Because of this, avoid buying highly modified ‘double’ and ‘triple’ bloomers or extra-petaled flowers that will likely inhibit a pollinator’s ability to feed.

Narcissus poeticus, Public Domain, https://commons.wikimedia.org/w/index.php?curid=907

Best Bulbs

Though we may associate the bulb trade with Holland, the native range of daffodils is the Iberian Peninsula and tulips grow wild in Turkey and Central Asia. Crocus were originally native to southern Europe, the Middle East and western China. There are some bulbs native to North America, such as Claytonia virginica and Mertensia virginica as well as the trout lily, but they are too often upstaged by fancy exotics. This link offers great options for North American native bulbs that will benefit you and the ecosystem. If you aren’t ready to give up your tulips and daffodils, never fear! By choosing unhybridized species, the flower retains its pollen and nectar, supplying much needed early spring feeding for hungry pollinators. Crocus, species-variety Tulips and Muscari all are well-loved by hungry bees waking up from their long hibernation as well as wild type daffodils such as Narcissus poeticus or N. jonquilla.

A bee visiting a purple crocus flower.
CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=660234

Claytonia is a lovely North American native. By Dcrjsr (Own work) [CC BY 3.0 (http://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons

Planting Tips

The first step to proper planting is identification – is what you are holding truly a bulb? Corms, tubers, rhizomes and true bulbs all fall under the category “geophyte” (a perennial that stores its food underground). Many rhizomes would not like to be buried as deep as a bulb but corms can be treated much the same. Sorting out the technicalities will ensure correct planting and big blooms!
When planting true bulbs, depth is essential. In general, plant bulbs 2 or 3 times as deep as its height. Example: a 2 inch tall daffodil bulb should be planted 6 inches deep. Digging too shallow is better than planting too deep since many bulbs have contractile roots. Over time, these specialized roots will pull it down to optimal depth. Planting root side down/pointed side up is always best, but if the bulbs are too odd-shaped to tell, plant them sideways to be safe. Thanks to geotropism, a plant’s ability to sense gravity and grow accordingly, they will eventually right themselves.

Bees love Fritillaria meleagris, a dainty and unique bulb native to Europe. By Пономарьова Алевтина (Own work) [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons

So, after much scouring of the internet it seems there is no straightforward answer to Brad’s question. Many highly hybridized bulbs do not benefit pollinators, but other heirloom or species varieties certainly do. To benefit early spring pollinators in your bulb garden, install a few North American species or try to find unhybridized varieties that retain their full species name and their ecological importance. Get out your sweaters and garden gloves, now is the time to get digging!