4 Modern Landscape Ideas for Ann Arbor, MI | Prairie Grasses and Clean Lines for Zone 6a

Ann Arbor has more real modern architecture than most cities its size, and the gardens around it are usually the part that never got finished. Mid-century houses on the wooded slopes of Ann Arbor Hills, low 1960s ranches in Georgetown and Lansdowne, and the flat-roofed and black-framed infill now going up on Water Hill and around Kerrytown all want the same thing: a level terrace, one strong path, and planting in bold blocks rather than a ring of foundation shrubs. Many of the mid-century lots are sloped and shaded by big oaks, so a modern design here is often about terracing and shade texture, not a sunny gravel court.

The palette has to be built for Zone 6a: winter lows of -10°F to -5°F, roughly 38 inches of precipitation a year at the University of Michigan station, and about 121 days a year below freezing. That rules out the agave and Mexican feather grass in most modern garden photos. Nassella tenuissima is not reliably hardy here, so use Sporobolus heterolepis 'Tara' for the same fine, moving texture; for the spiky accent, Yucca filamentosa 'Color Guard' replaces agave. The backbone that works is grasses native to the Southern Great Lakes forests ecoregion, Schizachyrium scoparium 'Standing Ovation' and Panicum virgatum 'Northwind', plus Calamagrostis × acutiflora 'Karl Foerster', which stands upright through snow and gives the garden structure in February. Clipped Taxus × media 'Hicksii' and Thuja occidentalis 'Smaragd' supply the evergreen green walls.

The ground is the engineering problem. Most of the city sits on glacial till, clay loams that stay wet in spring and shrink in a dry August, with lighter ground on the Huron River terraces. Frost in Michigan is designed for at 42 inches, so walls, pergola posts and fire feature bases need footings to that depth, and paver terraces need a deep, well-drained base or they will heave out of line, which is very visible in a design that depends on straight joints. Lodi Farms and Turner's on South Wagner both sell crushed stone and gravel by the yard, which makes a proper base cheaper than people expect. pH on the till is usually near neutral; check it with an MSU Extension soil test before amending.

The city's own rules suit the style. Chapter 40 of the City Code, amended by ORD-25-34 in December 2025, lets cultivated plants such as native grasses and perennials grow in the lawn extension up to 36 inches of foliage, with flower tops to 42 inches, while keeping plants under 30 inches within 40 feet of residential corners. A curb strip of Sporobolus 'Tara' and Allium 'Millenium' stays within that and looks deliberate, and street trees or shrubs in the right-of-way need written city permission first.