For many centuries, grasses have been a key component in European gardens, although until relatively recently these were limited to lawns or meadows. Since the latter part of the 20th century, ornamental grasses have been used more and more in our gardens. Even though they do not have the pretty, colorful flowers of most garden plants, they bring structure, height, texture, fall color, winter silhouettes, and—most important of all—movement. Some, such as Stipa gigantea and molinias, stand well into fall with their stems glowing golden orange, and grasses like miscanthus and calamagrostis remain attractive throughout the winter months and into the spring. The winter garden will look much more interesting if it has some grasses, because they don’t die down in fall like other herbaceous plants. The birds can also feast on the seedheads.
Grasses usually fall into one of two groups: clumpers or spreaders. Some
naturally form perfectly behaved clumps, whereas others can take over
your garden with their creeping rootstocks. So choose carefully. There
is now a large selection of grasses available that do not self-seed or
spread wildly. If in doubt, check with your supplier, or take a close
look at how the plant is growing. If it makes a neat, dense clump or
tussock, it should not run; if you see shoots coming up all over the pot
without forming a tight clump, beware. In light sandy soils in
particular, grasses, such as variegated gardener’s garters (Phalaris
arundinacea), can become invasive and need to be regularly weeded out.
Where to Plant Grasses
You can use grasses as solitary feature plants, or scattered through
other plants, or in larger drifts or swaths. How you do it depends on
the type of grass you choose and the effect you wish to achieve. Try
large drifts of Miscanthus sinensis ‘Kleine Silberspinne’—although not
the tallest grass, it is still impressive. Calamagrostis x acutiflora
‘Karl Foerster’ also looks good in a mass. You could use it to create a
hedgelike screen, or add depth to a bed or border by scattering it
through a planting of smaller flowering perennials.
Since many grasses stand through fall, you can create a beautiful effect by siting them carefully. The flower spikes and orange stems of Molinia caerulea ‘Windspiel’ or ‘Transparent’ glow if they catch the late afternoon sun in fall. As its name suggests, ‘Transparent’, like other molinias, is almost translucent. If you position it at the front of a planting, it creates a see-through screen, and the feathery plumes brush your face as you walk past. Sound and movement add an extra dimension to a bed or border when grasses rustle in the wind. Intersperse them among traditional flowering plants for contrasts of color and shape.