Garden Spotlight: Matrix Planting in Austria

Posted on August 23, 2023 by Janelle Flory Schrock

I can’t seem to go on vacation nowadays without being stopped in my tracks when I see examples of habitat gardening. I don’t know if it’s just a result of working at the Dyck Arboretum for over ten years, or a function of having been bit by the native plant bug (pun intended). Either way, I want to share with you an excellent example of drought-tolerant, wildlife-friendly plants being utilized in an urban setting.

This summer I visited Vienna, Austria and the surrounding areas, and was struck by several really well-designed perennial gardens. For example, while waiting for a bus, a matrix planting along a hospital accessibility entrance ramp caught my attention.

*I was delighted to see a matrix planting utilizing familiar (to me) perennials outside a clinic in Donaustadt, Austria.*

In the 10 minutes we were at the bus stop, my mind (and my camera) took in as much as they could. I immediately set out to identify how the landscape architect had successfully employed the design principles I’ve heard repeated time and again by my co-workers in their Native Plant School classes.

If you’re not familiar with matrix planting, it’s a landscape design style, popularized by Dutch landscape architect Piet Oudolf. Famous North American gardens using matrix planting include public garden spaces such as “The High Line” in New York City and Lurie Garden in Chicago.

In this particular landscape, I could easily identify the three layers of the matrix: the structural layer, the seasonal interest layer and the ground cover layer. In the structural layer, several small shade trees and a few larger perennials anchored the corners of the planting and in some cases softened particularly sharp edges of the hardscaping.

*Black-eyed susan and aster blooms provided a nice complementary color scheme.*

The seasonal interest layer included repeated blocks of switchgrass, feather reed grass, black-eyed susan, yarrow, asters, ornamental onion, tickseed, and others. Groundcover plants were interspersed throughout for weed management, particularly along the edges of the walkway.

*Repeated patterns along the walkway provided both visual and sensory stability.*

In addition to its visual impact, I also couldn’t ignore the sensory and emotional function that this garden was fulfilling. As my friends and I waited for the bus, we couldn’t help but walk over to feel the softness of the grasses. This planting certainly engaged multiple senses of passersby – providing a welcome contrast to the hardness of the concrete structures that surround it.

*The layers of plants soften the edges of this walkway, but also give patrons of the clinic something interesting to look at and feel as they enter and exit the building.*

There was also a rooftop garden that I imagine is a spacious area for visitors and patients to relax and connect with nature. I didn’t have enough time to run up to it, but I was able to identify switchgrass and Mexican feathergrass from below.

*A rooftop garden was also visible from the street.*

I was so very encouraged by my habitat garden sighting in Vienna. It’s a wonderful feeling to travel and see examples where someone, at some point, must have had the courage to speak up and say “Why don’t we plant a habitat garden here?” It will have a positive impact on our public and our neighborhood, but also on the environment.

We continue to receive more inquiries here at the Arboretum from all sorts of places: not only homeowners and homeowners associations, but also from for profit and not for profit business entities, and from churches, libraries and schools. The collective impact you are making in your communities is awe-inspiring. Keep it up and continue to share with us your habitat gardening challenges and successes!

Landscaping with Plant Communities in Mind

Posted on September 17, 2021 by arboretum-admin

This blog post is updated and republished. Previously published as “The Social Network for Plants” in September 2017.

One of the landscaping concepts I touched upon in my recent Matrix Planting class is the idea that plants are members of a complex social network. No, they are not on Facebook, Instagram or tweeting about the conditions on their side of the prairie, but they do grow best in a company of friends. I enjoy the idea that even though each plant is unique, they are part of interrelated communities. They complement each other and live in harmony, which makes them so much more resilient together than if they grow isolated and alone.

Plant communities in the wild

Nature is a great teacher. Look at wild plant communities. Whether a forest or a prairie, you will find plants growing harmoniously together. There aren’t any mulched areas between plants, but rather intertwining, interlocking and dense groups of plants growing side by side. A compass plant reaches up through tall grasses like big bluestem and indiangrass. The deep tap root punches through the fibrous roots of the grasses, and the tall grasses help prop up the compass plant’s long stems and keep them from flopping over. If you plant compass plant in your landscape, plant it with these tall grasses. Plants grow in environments that suit their growth habit.

Butterfly weed is another great example. In the wild, it would get smothered and lost in five to six foot grasses, but you see it flourishing with shorter grasses like little bluestem, prairie dropseed and blue gramma. Grasses of similar height is what they prefer. The beautiful orange blooms are at the same height as the grasses. These plants also have similar sun, soil and moisture requirements, too.

Know more about the plants you grow

An understanding of plant communities and the preferences of individual plants will help direct your landscape design. This approach to landscaping forces you to become familiar with each plant, but rewards you with a successful landscape that mimics the communities on the prairie. By adapting your gardens to include groups of plants that naturally occur together and that match your own landscape, you will have a functional, low maintenance landscape that is ecologically responsible and beautiful at the same time.

*Urban prairie photo courtesy Craig Freeman*

This style of landscaping has caused me to reevaluate how I design new plantings. For instance, switchgrass, which is one of my favorite grasses, is a solitary grass in the wild. It forms large colonies with other wildflowers growing on the edges of these colonies. Richard Hansen and Friedrich Stahl, in their book “Perennials and their Garden Habitat”, arrange plants according to their sociability level. Plants like switchgrass or coneflowers at lower levels (1 and 2) are set individually or in small clusters. Plants like prairie dropseed or blue grama at higher levels (3 to 5) are set in groups of 10 to 20-plus, arranged loosely around the others.

By observing the different levels of plant sociability, it guides how you incorporate plants into your landscape. It is an ecological way to garden that focuses less on aesthetics and more on relationships of plants. Of course height, bloom time, texture and flower color are important, but they are not the most important consideration when planting. The main emphasis now is grouping plants together that thrive in the wild together.

So what does this look like practically in your landscape?

It looks like 10-20 coneflowers (level 2 plants) propped up with little bluestem, prairie dropseed and blue grama (level 4 plants). In the wild, you never see just coneflowers growing in large solitary groups together, but mixed with other wildflowers and grasses. Blue sage (level 2 plant) has a tendency to flop, but when combined with other taller grasses and wildflowers, its blue flowers are held at eye level. The taller, more upright plants or solitary plants in levels 1 and 2 need the level 3 to 5 plants to grow and spread around them. This interlocking matrix of plants covers every square foot of your garden. Weeds are crowded out and maintenance is reduced over time as these plants squeeze out unwanted species. You can now manage your plant communities as a whole rather than taking care of each individual plant.

*Native prairie photo courtesy of Craig Freeman*

I believe this approach to designing a landscape has many benefits. Using this approach, we will become intimately acquainted with the plants we grow and the social communities in which they thrive. This connection to our plants forces us to learn about them. More importantly we begin to see them as individual pieces of a much larger collection of associated plants. It is a radical shift in how we design a garden. Plants are pieces that nature weaves together in ecological combinations. Nature is a great teacher.

Succession of Bloom

Posted on March 3, 2021 by Scott Vogt

Every gardener strives to have a continuous symphony of flowers in their gardens from spring through fall. However, most gardens, including some of mine, seem patchy in appearance with sporadic blooms from time to time. Although a continuous floral bloom is the goal, it is often not achieved unless a method called succession planting has been implemented.

Succession of bloom is used to describe a diverse set of plants in a flower border that will always have interest. At any given time during the growing season there are plants coming into bloom and fading out of bloom. This consistent bloom is important in a design, especially when using native plants.

*Tallgrass Prairie National Preserve in the Flint Hills.* *Photo by Brad Guhr*

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.

In my opinion, succession of bloom is one of the most important concepts in native plant design, right after site considerations and matching plants up to your site. Take time to acquaint yourself with the life cycles of wildflowers and grasses. The more you know, the easier it will be to seamlessly incorporate them into your design. Succession of bloom always provides something of interest in the garden, but it also provides season-long food for pollinators and other wildlife.

Starting a List

Put together a list of plants that bloom at different seasons and will grow well in your area. Include early season bloomers, midseason bloomers, and late season bloomers. Select a set of grasses that combine well with those wildflowers or provide backdrop for other perennials in front of them.

Native Plant Guide

*Working on a landscape design for one of our members.*

Begin the Design

As you layout your plants in your design, think about heights and layer of plants. Typically, there are only three or four layers of plants. Plants 4-18 inches tall in the front, middle layers of 18-24 inches and 24-48 and then taller perennials at 48+ inches tall. These tiers guide how I combine the plants and layout the design.

*Initial planting next to the Prairie Pavilion.*
*Needs more grasses and wildflowers to fill the gaps and cover the mulch.*

Layout

Always think about foliage and flowers. In matrix planting, made popular by Dutch landscape designer Piet Oudolf, every square inches is covered with plant material. From the groundcover layer through the seasonal interest layer and on up through the structural layer, plants crowd out weeds and mimic the prairie community. Keep in mind, blooms will fade, so foliage is important too. Seed heads can be supported and highlighted with grasses. A striking example is the dark seed heads of coneflowers later in the season with little bluestem.

*Little Bluestem and Pale Coneflower seedheads*

Plant in smaller groups

I prefer to plant is smaller groups such as five, seven or nine individual plants. Often, I will mix in some native grasses with the wildflowers. A larger swath of something out of bloom leaves a large void in the design, especially if it blooms in the spring. Plant closely enough so that foliage intermingles. If plants are spaced too far apart that there is more mulch or soil than plants, this void will draw your eye to the plant that is out of condition. By planting densely, you will hardly notice a plant out of bloom.

The example below is simplistic, but the concept is the same. Succession planting combines specific plants for your garden that all look good together and bloom at different seasons. Try to avoid planting two different groups of plants next to each other that bloom at the same time. Those groups will leave a larger hole in the landscape.

Example: nine coneflowers (pink) with five little bluestem ‘Twilight Zone’ (blue) planted next to seven Rudbeckia ‘American Gold Rush’ (yellow) which is planted next to three Aster ‘Raydon’s Favorite (purple).

Your pattern can be continued or another set of seasonal plants can be incorporated into the design. This is also a tier in the overall design. They are all about the same heights. Plant something taller behind and shorter in front of these perennials.

Succession planting is very rewarding, and these simple techniques should guide the process. Again, take time to acquaint yourself with the life cycles of wildflowers and grasses. The more you know the easier it will be to combine them according to bloom time. Succession planting is something that we all respond to, and brings the garden together visually.