Sporobolus heterolepis 'Tara'

Sporobolus heterolepis ‘Tara’, a dwarf form of the species, is one of the showier plants of the matrix layer.

Plants are the very essence of a garden’s style, the ingredients with which we plant indelible memories and emotional experiences. I’m unabashedly obsessed with these components, the materials for making beautiful and functional landscapes, so much so that my process for making gardens begins with a consideration of the details. Many professional designers might scoff at that approach, favoring something more conceptual layered with successive amounts of detail (of which plants are often last). But the design process, or dare I say the process of expressing and fusing nature and humanity in a common landscape, isn’t linear. It’s spasmodic and at times perambulating, a journey through understanding place.

The concept for Meadow Nord evolved early and fast, something I felt sure about given the context of the land. The savanna archetype–the interstitial ecological zone between forest and grassland–felt especially right given the species composition of nearby parkland (which effectively envelopes my neighborhood to the west, south and east). Oak trees hold forth in canopy and sedges reign below; the sunnier edges give rise to Elymus spp. (wild rye) and Schizachyrium scoparium (little bluestem). For the last few weeks, Gentiana alba (cream gentian) and Symphyotrichum cordifolium (blue wood aster) have flowered in succession, following on the heels of a monthlong profusion of Rudbeckia triloba (brown-eyed susan), which seems to grow in all the neighborhood gardens. Though the product of disturbance in an urban-influenced environment, the local diversity is seasonally rhythmic and inspiring.

(I even found small outcroppings of Diarrhena obovata, our local beakgrass much beloved by wild turkeys. My friend and fellow plantsman Allen Bush just wrote about the more eastern species of Diarrhena on Garden Rant. These aren’t the showiest of grasses (nor do they have the best name), but they are remarkably functional and serviceable.)

This isn’t to say that ecology drove the decision entirely. I wanted something to connect my house, a two-story 1941 Colonial Revival, to the extensional parkland landscape. I was already blessed with the noble canopy of oaks to frame the view from the street, so this planting could afford looseness so long as it abided by the boundaries. The planting scheme in most places won’t grow over 3-feet tall and with more than 125 linear feet of curb, even if a few plants tower to greater heights, they won’t disrupt the composition as it sweeps over the front yard. I’ve planted the beginnings of a minimal and informal hedge at the foundation of the house featuring, among other things, Hydrangea arborescens ‘Haas’ Halo’ and Aronia melanocarpa ‘Iroquois Beauty’. Additionally, most of the structural plant groupings in the meadow contribute to the effect while not overwhelming the house.

Understanding Soil

On a hill above the river set in a neighborhood called Oak Park, I wasn’t surprised to find “loamy upland forest” soil, as described by the USDA’s Web Soil Survey. Those soil surveys build on historical data recalibrated every so often by contemporary usage, climate, etc. In cities, soils often fall into “complexes” variously described by their parent historical soil type (in my case the Hayden series) appended with the reminder that in urban environments, the soil underfoot might be as far removed from its natural history as you could imagine. The Hayden series is a calcareous, glacial loam with moderate to high alkalinity; the standard stuff of central and northern Iowa and southern Minnesota.

Durable Assumptions

My goal with planting Meadow Nord wasn’t to create perfection within a frame, but instead operate within a realm of durable assumptions. Every gardener makes assumptions about plants. Occasionally, we plant something with a hope and a prayer, but more often than not, we intend for a plant to do something on account of its size, ornamental traits or the position we’ve given it in the garden. Plants aren’t always so compliant. In a 3,200 square foot meadow, you can measure assumptions by the yard.  My spreadsheet notes about the matrix layer reveal a combination of insights, intentions and hopes that this novel assortment of players works together in concert.

Antennaria neglecta Matrix Full sun; driveway edge
Antennaria plantaginifolia Matrix Part sun, dry shade; path edges
Carex albicans Matrix Clumper, sun + part shade
Carex blanda Matrix Rhizomatous, savanna edge; groundcover for taller grasses
Carex pensylvanica Matrix Rhizomatous, shade
Carex sprengelii Matrix Rhizomatous, shade; likes moisture
Carex woodii Matrix Rhizomatous, dry shade; under oak
Deschampsia caespitosa Pixie Fountains Matrix Clumper, sun + part shade
Diarrhena americana Matrix Full shade; oak tree
Eragrostis spectabilis Matrix Full sun; driveway edge
Eragrostis spectabilis Matrix Full sun; driveway edge
Galium odoratum Matrix Full shade
Geum triflorum Matrix Full sun; open areas
Molinia caerulea Moorflamme Matrix Full sun; open areas
Ruellia humilis Matrix Full sun; open areas
Sporobolus heterolepis Tara Matrix Full sun; open areas
Tiarella New Moon Motley Matrix Full shade; oak tree

My personal challenge was to experiment with plants beyond the realm of my hands-on experience. I gambled lightly on the matrix (as critical of a layer as this, I felt more comfortable planting known quantities); only six taxa above are new to my gardening experience:

  • I have admired Antennaria plantaginifolia since I encountered it in the Ozarks in 2009. It’s a remarkable, durable plant of the savanna understory with dashing silver foliage.
  • Carex albicans, C. blanda and C. woodii are new sedges to me, though in the case of C. blanda, I’m sure I’ve weeded it out of my woodland garden at the farm over the years, unknowing and indignant of its value.
  • I mentioned Diarrhena americana and the more Midwestern native D. obovata already in this post. I have my own seed collections of the latter, which I would have rather experimented with, but not in the quantity I ultimately needed. D. americana was available from Midwest Groundcovers and suffices ornamentally and functionally for the same purpose (and from what I can tell already, the turkeys that trek through my garden happily consume its seeds).
  • For as many heuchera and tiarella as I’ve killed over the years (and for as many as I love and adore), Tiarella ‘New Moon Motley’ was a strain from New Moon Nursery with red-marked leaves and a robust running habit that I hadn’t encountered before. It features prominently in a groundcovering role underneath the canopy of Big Bur.

Post-planting, I have confidence in my approach and palette, but could use additional Carex albicans, which as a sun-tolerant and clump-forming sedge has a lot of value for my site given its exposure and the floral complexity of the above-ground layers (which I’ll break down and detail in future posts). It’s good for intermingling, a polite and unfussy socializer. I could say the same of Eragrostis spectabilis, but I know it will eventually move its way into the handful of spots where I wish there was more. While the matrix layer of plants doesn’t attract as much attention in horticulture as it should, it’s critical to success in these complex-by-design plantings.