Katie’s Weeding Guide Part II

In a previous blog post I discussed tips for common weed identification, but hinted at a second installment covering plants that don’t quite qualify as weeds. After all, a weed is just a plant out of place! Some lovely native flowers have ‘weedy’ tendencies but don’t deserve total eradication from the garden. Here is an introduction to a few of those characters, and what you can do to control them when weeding your gardens.

Spiderwort – Tradescantia ohiensis or T. tharpii

A lovely member of the dayflower family, spiderwort puts on a wonderful show throughout spring.

Ranging from true blue to purple, spiderwort germinates readily from seed and can quickly take over a garden. I find it in every garden we have here at the Arboretum. Hairy leaves with purple veins and a pronounced fold along the mid vein are easy ways to identify spiderwort. The short stemmed species (T. tharpii) is a nice filler around other perennials and will grow as a ground cover. T. ohiensis is taller and more unwieldy, crowding out desirable plants. When Arboretum volunteers are weeding, I ask them to remove all but a few intentional clumps. I cut the flowers frequently to prevent those clumps from seeding.

Prairie Petunia – Ruella humilis

So petite but not so polite, Ruella spreads rapidly and travels all over the garden, thanks to its exploding seeds pods. White, pink, or lilac flowers are borne on purple stems with deep green foliage. With a mainly prostrate habit, this creeper makes a nice border plant, especially spilling over rock edging. Deep rooted, it is hard to pull once mature. If these fellas get started in your garden, regular weeding won’t do it – you will need to dig them out. But maybe they are the free, fast growing ground cover you have been looking for!

Curly Cup Gumweed – Grindelia squarosa

Gumweed can be found growing north of our Prairie Pavilion, but not for long! I am overdue in weeding them out. This western US native is cheery and adorable, but too wild to be running amuck in our formal gardens. I’d be much happier to see it growing in our prairie or around the pond edge. If you have the space, don’t pull them all out – it is attractive to pollinators and can be controlled by cutting the flowers before they seed. 

Public domain image, USA

These are just a few of the weedy native flowers that your soil’s seed bank may be harboring. Perhaps they can find a happy home in your garden, as long as you are willing to tame their bad habits. 

Growing future gardeners through Earth Partnership for Schools

This week, is National Public Gardens Week.  All week we are celebrating, with other public gardens around the country, the unique role botanical gardens and arboreta have in our communities and neighborhoods. 

In the last month we have been preparing for and hosting many different events and celebrations, including our spring FloraKansas Native Plant Festival, during which we sold over 15,000 plants.  During graduation weekend, there were several graduation receptions and parties, and in the next two weeks we will host four weddings, a college alumni luncheon and the Kansas Native Plant Society board meeting. 

We are happy to be part of this community.  Your support helps us fulfill our mission to cultivate transformative relationships between people and the land.  We are truly grateful. 

FloraKansas Native Plant Festival

Over the past several weeks, I have been reflecting on how/why I got into this crazy world of horticulture.  I think it started by working in the vegetable garden and then planting trees around our family farm.  Like most teenagers, I grumbled, but at some level I enjoyed it.  I had the opportunity to get my hands dirty and establish plants that I watched grow and mature.  It started simply, with a little curiosity and enjoyment of being in nature. 

The Dyck Arboretum of the Plains Earth Partnership for Schools (EPS) program takes the same approach.  Through the training of teachers, we are able to introduce generations of students to the wonders of prairie plants and the pollinators and wildlife they attract.  Children are naturally curious and these school prairie gardens are an oasis and teaching tool in science, math, music, art, biology and so much more. 

For many of these students, these prairie gardens may provide the first opportunity for them to plant a plant or watch a monarch butterfly on their milkweeds.  These students are the next generation of land stewards.  The more they understand and appreciate the land, the more they will be able to care for and protect it for future generations. 

Fourth graders at Sunset Elementary in Newton, Kansas, investigate a common milkweed plant for monarch caterpillars.

We believe the EPS program, which is celebrating its thirteenth year in 2019, is vitally important in shaping future leaders who are aware of and connected to the natural world around them. 

As part of our membership in the American Public Gardens Association, we have the unique opportunity to participate in a one-week-long, flash fundraising campaign, called the MYGARDEN campaign.  We are seeking funding support for the upcoming EPS summer institute.  This year we are hosting over 30 teachers from 12 schools. Help fund their participation in this inspiring week of training.  To date, over 40,000 Kansas students have been impacted by the EPS program.  Your gift will have an impact now and into the future as more children become stewards of the land.     

Kansas Native Ferns

At FloraKansas Native Plant Festival our customers were surprised to see we offer Kansas native ferns. Perhaps they were surprised to hear Kansas even had native ferns! With our hot, dry summers and deep-freeze winters, Kansas does not seem like hospitable environment for delicate, shade loving plants. However, we have several naturally occurring fern species in the state that are hardier than you might think. They are fascinating to observe growing in the wild, but also make excellent additions to your shade garden.

Royal Fern

Osmunda regalis var spectabilis


According to fossil records, the royal fern family (Osmundaceae) dates back about 365 million years. 3 to 4 feet tall (shorter in poor, drier soil), this fern becomes a large and impressive specimen in the shade garden. O. regalis var spectabilis grows happily in the far eastern part of Kansas and throughout the eastern third of North America. Royal fern has attractive bright green foliage and rust colored spore plumes. It prefers moist, somewhat acidic soil and shade though it can handle sun if the soil is kept wet. This fern can live up to 100 years if planted in the right location!

Royal fern is an easterly species, occurring from the Ozarks through the southeastern US and north into eastern Canada.

Christmas Fern

Polystichum acrostichoides

This festive native fern grows in far southeastern Kansas. According to Missouri Botanical Garden, it “…typically grows in a fountain-like clump to 2′ tall and features leathery, lance-shaped, with evergreen (green at Christmas time as the common name suggests) fronds.” If you love boston ferns but want something perennial, this is a great option. When planted in an average moisture, shaded area it will spread slowly to form a colony.

If you are up for some botanizing, head to these southeastern counties in moist, partially wooded areas to catch a glimpse of these ferns.

Sensitive Fern

Onoclea sensibilis

Onoclea is unique native fern, with arching fronds and oblong, creeping rhizomes. Getting its name from sensitivity to frost, O. sensibilis is surprisingly hardy. It can easily survive the cold dry winters in Kansas, Nebraska and even the Dakotas. This species is native to the eastern half of North America as well as far eastern Russia and China. According to Wikipedia, you can help your ferns survive the winter by leaving dried fronds on the plant instead of clearing them away.

There are many more native ferns I could include here, from the marginal woodfern found in Wilson, Elk, and Greenwood counties to the tiny rock ferns growing among the monoliths at Rock City in Minneapolis, KS. Get out and do some fern hunting, or buy a few at our fall sale to enjoy for years to come.

Callery Pear: Cut Them Down

Several years ago, I noticed something disturbing was happening to our prairie reconstruction.  Small little trees were popping up throughout the original prairie planting.  I could not figure out where they were coming from, but they looked like pear tree saplings.  It wasn’t until I saw a large white blooming tree in the spring that it all came together. 

Callery Pear

Although the flower clusters are beginning to fade, Callery pear’s white blooms are most obvious in the spring.  We planted them for their explosion of spring blooms and nice fall color, but this ornamental tree has become highly invasive.  It threatens native wildlife habitat and has become a nuisance for private and public landowners.

This once favorite tree was planted extensively throughout the U.S.  The Callery pear – also referred to as Bradford pear – formed a nice pyramid to rounded shape.  The vertical limbs made it a nice median and street tree as well, ultimately reaching 30 to 40 feet tall and 20 -30 feet in spread.  This Chinese native was a harbinger of spring for decades with its prolific white blooms.  An added bonus was its reddish-purple fall color.

Despite all those positives, these trees have become problematic. This non-native, flowering tree was assumed to be sterile, but it is not.  It now cross-pollinates with other cultivars of Callery pear to produce hybrid offspring.  The fruit is ingested by wildlife and birds that spread the seeds across the countryside and into your yards.  It is aggressively displacing native vegetation, causing economic and environmental damage. 

Escaped Callery Pears*

The message to property owners is to remove the trees now while you can easily identify them in bloom.  We need to keep them from spreading to native areas.  It doesn’t hurt my feelings to see them go, because they are a weak-wooded, thorny mess. 

Native alternatives to Callery Pear:

  • Eastern Rudbud (Cercis canadensis)
  • Serviceberry (Amelanchier arborea or Amelanchier ‘Robin Hill’)
  • American Plum (Prunus americana)
  • Chokecherry (Prunus virginiana)
  • Blackhaw Viburnum (Viburnum prunifolium)
  • Rusty Blackhaw Viburnum (Viburnum rufidulum)
Blackhaw Viburnum in spring
Blackhaw Viburnum fruit and fall color

We have cut down the culprit, but still have a bunch more saplings to remove this summer. There is one more larger tree to cut down near the Visitor Center. We will continue to eradicate these unwanted invaders in our prairies.  It will take time but I believe we can get the upper hand.  I would encourage you to remove them in your landscape as well and replace them with native trees.  Callery pear has no place in the landscape anymore. 

*Image Source