Hartley Magazine

All the latest news, hints, tips and advice from our experts

How a prairie works, and how to capture a little bit of prairie in the garden

As late summer falls on the Midwest, prairies turn golden as grasses dry, their seed heads ripen and flowers are in their glory.

There’s little virgin prairie left today. But some prairie plants have found a haven in our gardens. Coneflower (Echinacea), black-eyed Susan (Rudbeckia), blazing star (Liatris), blanket flower (Gaillardia), prairie dropseed (Sporobolus), switchgrass (Panicum) and other Midwestern natives have become common in catalogs and garden centers (often in bizarre hybrid forms bred to feed some gardeners’ insatiable appetite for anything new).

black-eyed Susan (Rudbeckia)

Most people simply work these plants into borders with perennials from around the world. They work great in temperate-zone climates — Zones 3 to 7. They also provide the seeds and nectar that our native¬† ¬†wildlife is evolved to depend on.

But if you understand the prairie ecosystem in which these plant evolved, you also can find ways to use their special properties to reduce your garden’s need for maintenance, water and fertilizer.

The Midwest has a wildly variable climate: from below-zero to sweltering, from heavy rain to drought, from 4 feet of snow in one winter to bare and mild the next. In spring and fall, 50-degree temperature swings in 24 hours are pretty standard. So prairie plants needed to be resilient and unflappable.

To survive, they evolved to grow long, deep root systems — as much as 10 feet deep and wide. These roots stretch out to find whatever water is in the soil, even in drought. They survive any winter. ¬†As the buried roots die and decay, the resulting humus enriches the soil, along with the dead top growth when the plants die back every fall. Over 10,000 years, this created some of the richest soil in the world.

So, in the garden, prairie plants need soil that is rich in organic matter. They need full sun (there’s no shade out on the prairie). Once established, they rarely need watering or fertilizing. They thrive on neglect from people, but they like the company of other prairie plants.

Above all, to succeed as garden plants, prairie natives need to be chosen well. ¬†There are different kinds of prairie — wet, dry, seasonally wet; tallgrass, shortgrass, mixed with trees — and as with any plants, it’s important to choose species that are genetically adapted to do well in the particular conditions of the¬† site where you are planting.

When I was a newbie gardener, I had one sunny bed 50 feet long and only 18 inches wide, right next to a crucial sidewalk. Naively, I planted a variety of tallgrass prairie plants, including tall coreopsis (Coreopsis tripteris). They did what comes naturally: They grew happily 5 to 7 feet tall and, since they weren’t part of a supporting prairie of equally tall plants, they flopped all over the sidewalk, driving people nuts. I found new homes for the tallgrass prairie plants. My current rule for that bed is: no more than knee-high.

The seeds of prairie perennials and grasses need a cold winter to germinate. ¬†Plant them in small containers in the fall and leave them outside until early spring. Then you can bring them into a cool greenhouse to sprout and spend their first few weeks as seedlings. But plant them outdoors right after your area’s average first frost date and keep them watered through their first year. They are unlikely to bloom the first year, but they will have had a chance to start on that long, deep root system.

You’ll get the most benefit from the toughness of prairie species if you group them, either with other prairie species or with equally self-sufficient perennials. The neediest plant in a bed, border or container — the most tender, the most thirsty, the most disease-prone, the most in need of fertilizer — determines how much attention you have to give the whole thing. So plant your most self-reliant plants together and, once they have time to establish themselves, you will have little work to do there.