Written by Peter Grimaldi, Vice President of Gardens & Facilities at Cheekwood
Ornamental grasses are commonly emphasized in garden design for winter interest, and the summer months present an important opportunity to appreciate and manage our perennial grasses as spring blooms fade and our gardens settle into various shades of green.
Imagine your garden in black and white for a moment or, better yet, take a series of black and white photographs over the course of the growing season. The thoughtful use of plants with variation in size and texture creates a visual framework for your garden that helps organize the experience as the space is meant to be enjoyed, whether you are establishing a formal geometry or a loose rhythm through a more fluid design. Evaluate your space for contrast that either breaks up the planting areas into organized frames or moves the eye through the space. Textural contrast creates these visual cues and distinctions and understanding the differences in plants’ textures is essential to designing garden displays.
Plants with large leaves are said to have coarse texture and begonias, hostas and magnolias are good examples. Coarse-textured plants are classically featured toward the back of a mixed border where larger, foundational elements help to create a background for more intricate garden expressions.
Plants with small or thin leaves are said to have fine texture and ornamental grasses are the most effective way to achieve fine texture in the garden – lantana, aster, and elms are also good examples. Fine-textured plants are traditionally featured toward the front of a mixed border and function well in sweeps and masses. There is a full spectrum of texture, just as there is color, and designing with size and texture is critical to creating garden spaces that are legible and visually pleasing.
Ornamental grasses are useful in the full range of design applications between formal garden layouts to fully naturalized meadows. Plant selection is critical to design success, as always, and three genera dominate the ornamental horticulture market: Pennisetum, Miscanthus, and Panicum. Pennisetum, or fountain grass is notable for is range in size and color, as well as the distinctive bottlebrush flowers. Miscanthus, or silver grass, features more dramatic, feather-like flowers and a good selection of variegated cultivars. Panicum, or switchgrass, trends toward a more natural aesthetic and can stun with bright red and burgundy fall color.
Quick tips for successfully growing grasses include planting in the fall alongside your other perennials, six to eight weeks before first frost; dividing larger clumps in the spring for propagation and to manage plant health; and cutting-back larger growing varieties by up to fifty percent in the early summer to keep the grasses in-scale and prevent flopping.
For more information, The Color Encyclopedia of Ornamental Grasses by Rick Darke is generally regarded as the authoritative reference book and Hoffman Nursery (www.hoffmannursery.com) leads the production industry and produces excellent educational content, despite not selling direct to consumers.