With the popularity of ornamental grasses, gardeners are trying to think of ways to integrate these lovely plants into their gardens. What are the best companion plants for ornamental grasses? Will maiden grass mix with petunias?

First, consider the concept of scale. Grasses come in many sizes, from small mounds of blue fescue to towering plumes of Indian grass. Companion plants should be scaled appropriately. But that doesn't mean you should only plant 6-foot-tall flowers with your 6-foot-tall miscanthus. On the contrary, different heights give the garden a pleasing, layered look.

Another concept to consider is balance: Several small plants may be needed to balance one large plant. Don't give in to the temptation to simply plant one of everything. If you are gardening on a tight budget, choose self-sowing annuals to fill in quickly.

Also consider the season of bloom. Most ornamental grasses bloom in late summer to fall. Naturally, they look best paired with late-blooming flowers. But we want our gardens to look great all season. Try some early-blooming flowers and bulbs. Ornamental grasses can be used to hide dying bulb foliage.

Plan for a winter landscape. Most grasses look nice throughout winter, until they get buried by a heavy snowfall. Consider adding needled evergreens, weather-resistant garden ornaments, and flowers with attractive seed heads. Think of the winter garden as a gigantic, dried flower arrangement. Small trees and shrubs provide year-round structure. They are often referred to as the bones of the garden.

Finally, ornamental grasses look good with each other! Even a small garden has room for several well-placed grasses. You could combine one large Miscanthus with two or three medium-size grasses. Add some colorful flowers, and you'll have a garden that looks like it was designed by a famous landscaper. Aim for different heights, textures and colors.

Native Companion Plants for Ornamental Grasses

Ornamental grasses are essential in a prairie-style garden to achieve a natural look. These types of gardens are very inviting to wildlife, and it makes sense to use native plants, which provide shelter and food for wildlife. For more details, see my articles on hummingbirds, butterflies and beneficial insects.

Of course, many non-native plants also support wildlife and have great ornamental value. I personally enjoy a mix of native and non-native plants in my own garden.

So here's my list of companion plants for ornamental grasses. I've separated them into groups of tall, medium and short flowers to go with different sizes of ornamental grasses, but feel free to mix them up. For example, you can use tall grasses as a backdrop for medium-height grasses and flowers. Then place the short ones at the front of the border.

Remember to give ornamental grasses and perennials room to grow. You can fill in the gaps with annuals to make the garden look lush until the perennials reach their mature sizes.

Companion Plants for Tall Ornamental Grasses

These flowers look good with grasses that grow 5-7 feet tall like Miscanthus and Feather Reed Grass.

Agastache rupestris - Bushy perennial with orange flowers for hummingbirds.

Antirrhinum braun-blanquetii - Perennial snapdragon. Light yellow flowers.

Cleome - Tall stems of pink, purple or white flowers. Annual companion plant.

Cosmos - Late summer annual in a variety of colors, heights and styles.

Digitalis ferruginea 'Gelber Herold' - Like a tall exclamation point in the garden. Perennial.

Echinacea (Purple Coneflower) - A classic companion plant for grasses. Native.

Gaura lindheimeri - Graceful, native perennial with pink-tinged white flowers.

Liatris (Blazing Star) - A vertical accent with purple flowers. Native perennial.

Lychnis chalcedonica - Bright, scarlet-red or salmon-pink flowers on tall stems. Perennial.

Oenothera 'Lemon Sunset' - Light yellow evening primrose on tall stems.

Perovskia (Russian Sage) - Bushy perennial with lavender-blue flowers.

Rudbeckia hirta - Annual or short-lived perennial with warm colored flowers.

Salvia azurea - Tall perennial with azure blue flowers in fall. Native wildflower.

Verbena bonariensis - Tall clusters of purple flowers. Self sows prolifically.

Companion Plants for Medium-Size Grasses

Try these with grasses that grow 2-4 feet tall like Big Bluestem, Little Bluestem, Pennisetum, Mexican Feather Grass, Northern Sea Oats and Switch Grass.

Calendula - Annual with orange, yellow or apricot flowers. Easy to grow.

Coreopsis 'Sunray' - Bright golden-yellow flowers. First-year blooming perennial.

California Poppy - Drought-tolerant annual in a wide range of colors.

Gaillardia - Native perennial. Gives the garden an instant southwestern look.

Geum - Scarlet-red flowers or golden-yellow flowers. Long-blooming perennial.

Lavatera - Annual with large, cup-shaped flowers in pink or white.

Lavender - Shrubby evergreen perennial with fragrant flowers.

Oenothera missouriensis - Large lemon-yellow flowers. Native wildflower.

Penstemon - Drought-tolerant, native perennials with tubular flowers.

Petunia - Wild species look best with ornamental grasses. Annual.

Platycodon grandiflorus (Balloon Flower) - Blue, white or pink flowers.

Salvia - Perennials and annuals with blue, pink, purple, red or white flowers.

Snapdragon - Annual or short-lived perennial in a wide range of colors.

Zinnia - Late summer-blooming annual in a wide range of colors.

Companion Plants for Short Ornamental Grasses

These flowers are useful for edging, or for planting in the rock garden, along with grasses that grow 1-2' tall like Blue Fescue, Prairie Dropseed and Sedge.

Alyssum saxatile (Basket of Gold) - Masses of bright yellow flowers on a compact plant.

Aster alpinus - Spring-blooming perennial with lavender-blue flowers.

Dianthus - Compact perennials and biennials with pink, red or white flowers.

Ipomopsis rubra - Scarlet-red flowers for attracting hummingbirds. Biennial.

Viola - Annual or short-lived perennial. Good with shade-tolerant grasses.

Recommended Books

Gardening with Grasses by Michael King and Piet Oudolf