Landscaping with ornamental grasses

Ornamental grasses make excellent screen plants to hide unsightly propane tanks and air conditioners, or for privacy around patios and decks. They develop faster than shrubs. Professional designers mix a variety of grasses with perennial flowers and woody plants, sometimes massing them for showy effects. Grasses range in size from tiny pillows less than a foot tall to huge clumps over ten feet tall. They come in a range of colors from dusty blue to pink and purple.

Maintaining grasses is easy. Most grasses grow in nice neat clumps, and need only a once-a-year haircut. They live for years, are tolerant of drought and don’t attract pests or diseases. Fertilizing each year will help them look their best; a pound or two of Plant Tone scattered around the root zone is all they need.

Established grasses tend to die out in the middle of the clump, which then becomes a ring or donut shape. This is because they exhaust the soil in the middle. To revive them, simply cut out the middle of the clump and add some topsoil and plant food.

You should cut grasses down to the ground once a year, when they are dormant (between late fall and early spring). Some grasses make a mess in the winter, but most will stay nice and neat to provide winter interest. Birds like the seed heads, so leaving them until spring provides forage for our feathered friends.

A good way to compare grasses is by looking at the size they will be when they are fully grown. This way you’ll be sure to space them properly and allow enough space for them to develop to their fullest. Most grasses do best in full sun with plenty of moisture, but the most popular grasses are quite adaptable and will do well almost anywhere. Hardy grasses are perennials and will return each year larger.

Here are some of our favorites:

Miscanthus, commonly called “maiden grass”, has a very graceful habit, softly drooping and waving gently with the slightest breeze. Some have “zebra stripes’, others have stripes along the leaves. Miscanthus are great for privacy or screen plantings, and come in many sizes. The biggest and most spectacular is “Gracillimus”, which can expand as much as eight feet wide. “Adagio” has the same graceful habit but is smaller; a better fit for most landscapes.

Pennisetum, or “fountain grass” is another popular grass family. They have showy seed heads in various colors. Pennisetums work well in perennial borders or foundation plantings, mixed with flowering plants and shrubs. Our favorites are “Hameln”, which spreads to three feet, and “Little Bunny”, a cute one-foot accent plant for perennial beds.

Some grasses have an upright form that works well in tight spaces. The popular “Karl Foerster” feather reed grass has attractive wheat-like seed stalks that stand straight up, great hiding unsightly utility meters and air conditioning units. Panicum “Shenandoah” gradually turns purple during the season, and it grows in a tidy upright clump that looks great in foundation plantings.

Pay attention to the hardiness zone when buying ornamental grasses, or you could buy varieties that aren’t hardy perennials in this area. Southwest Ohio is in Zone six, so you should look for zone six, five or four. “Pink pampas grass”, shown often in color-enhanced mail order catalog photos, is not hardy in Ohio winters. Red fountain grass (Pennisetum purporeum) is popular for planters. We think of both of these as annuals and pay less for them than perennial grasses.

Steve Boehme is a landscape designer/installer specializing in landscape “makeovers”. “Let’s Grow” is published weekly; column archives are on the “Garden Advice” page at www.goodseedfarm.com. For more information is available at www.goodseedfarm.com or call GoodSeed Farm Landscapes at (937) 587-7021.