Grass is beautiful – clean lines, delicate flowers, subtle colours, fluid movement… In conventional gardens, it has played an important but supporting role – mowed and contained to provide a setting for buildings, specimen trees and other plantings.
These days, however, grass is a star and garden centres are offering extensive selections from around the world.
Many of the more stunning species are North American. Andropogon (Bluestem), Sorghastrum (Indian Grass), and Panicum (Switch Grass) were the dominant grasses of the Tall-grass Prairie, which, along with the Mixed-grass Prairie and the Short-grass Prairie, once stretched across the continent’s central plains.
Only one per cent of the Tall-grass Prairie remains – the most significant unbroken area being four million acres of the Flint Hills region in Eastern Kansas, which was too rocky to plough. Although much of Ontario was covered by wetland or forest, there were extensive grasslands in the southwest of the province. Remnants survive on Walpole Island (Bkejwanong First Nation) near Wallaceburg and in the four parks that make up Windsor's Ojibway Prairie Complex.
What an amazing sight the prairie must have been, an endless vista made up of hundreds of species of grasses and wildflowers, bending to the wind. The native grasses, some growing seven feet or more, are high in protein and make excellent forage; they supported great herds of bison that were the foundation of the economy of the Great Plains tribes.
Introducing these grasses into the home garden seems rather like installing a tiger as a housepet. Tall grasses make a dramatic statement, and they are tenacious. The saying goes: In the first year grasses sleep, in the second they creep, and in the third they leap. So location requires careful consideration - moving a deep-rooted grass like Andropogon is going to be tough after it is established.
The question is whether to incorporate grasses into existing plantings or give them their own area. I have seen grasses used to great effect in a minimalist formal setting – well-spaced specimens planted in sand or gravel, allowing a full appreciation of their form. It’s a design that makes a virtue of the gardener’s instinct to collect one of everything and allows for easy access to control growth within the available space. A suggested guide for how much space to leave between the plants is to take the mature height and divide it by half.
Drifts of grasses, for those who have the space, capture something of the feel of the prairie. But it’s worth remembering that grasslands were the sum of many plant communities, as reflected in this description, on the Ojibway Nature Centre
website.“A visit to a prairie site on Walpole Island in mid May is breathtaking. By then, the black landscape of an April burn has been replaced by a carpet of Small White Lady's-slipper orchids, Golden Alexanders*, Blue-eyed Grass*, Yellow Stargrass, Arrow-leaved Violet, Wood-betony and Hoary Puccoon. Unlike hardwood forests where the wildflower display is most extensive in the spring, Ojibway prairies undergo a slow buildup of colourful blooms which reach their peak in late July. Mid-summer brilliance is displayed by the tall culms of Culver's-root*, Butterfly Milkweed*, Flowering Spurge, Ironweed, Dense Blazing Star, Tall Sunflower, Prairie Dock and Tall Coreopsis. these waist-high wildflowers flow with the ever-present breeze. By August the flowering heads of Prairie Cord Grass, Big Bluestem* and Indian Grass* reach three and four metres high!”
These tall grasses are warm-season grasses. Before planting, it’s important to understand how they differ from cool-season grasses (including those used for lawns), which have their main growth in the spring and early summer and tend to go dormant in the heat. Warm-season grasses are somewhat dull early in the year; they reach their peak display in late summer and fall. That’s why they’re crowding the shelves in garden centres at this time of year. The late-season interest is a factor to consider when deciding where to plant.
*On sale at Return of the Native.