Home gardening has changed in recent years with the increased use of ornamental grasses in design. Grasses provoke very interesting responses from my clients. They either love ornamental grasses, or they don’t.
Why plant ornamental grasses?
It’s hard to get around the fact that ornamental grasses once established, are relatively low-maintenance. A quick clean up in May, a bit of fertilizer, and you’re good-to-go for the season. Most grasses are drought tolerant once established, and most do well in a wide variety of growing conditions. With the slightest breeze, ornamental grasses offer movement and sound to any garden space. They provide year-around interest, even in winter with their attractive seed heads and unique foliage.
I personally like the architectural shapes ornamental grasses offer a landscape. The narrow, upright habit of lean grasses is ideal for creating privacy screening, whereas, the wispy shape of shorter grasses creates spectacular borders or hedges. For a bit of drama in the garden, select the sturdy, arching blades of a large specimen grass, or tuck delightful dwarf grasses in with flowering perennials for added texture. There is truly a place for at least one or two ornamental grasses in every garden, no matter whether your style is formal or informal.
Ornamental grasses, I use over and over in design
Karl Foerster Feather Reed Grass (Calamagrostis)
Karl is a very reliable grass that can handle a wide range of conditions and still look good. Don’t we all wish we could be like that. Tall but not too tall, Karl reaches just over 48 inches in height and about 24 inches across in full sun. A cool-season grass – this means Karl will start growing in May before temperatures get too hot and continue to grow in the fall when temperatures cool – Karl regularly flowers in July. Use as specimen, planted in groups for impact, or as a low privacy screen. Green summer foliage turns golden-yellow in the fall. Zone 4.
Blue Oat Grass (Helictotrichon)
Blue oat grass is one of my favorites. Mix the blue foliage of oat grass with white flower perennials and shrubs for a stunning garden combination. Low growing, cool-season grass to a height of about 30 inches tall and wide, blue oat grass makes a wonderful hedge along a walkway or tucked in along an accent wall. Blue oat is not fabulous for the first growing season – it looks really spindly and I’m sure clients have wondered why I’ve given them this grass – however, the second season is when blue oat grass hits its stride. Big domes of blue foliage with tall panicles of beige seed heads grace this grass in summer. It does need full sun for the best results, and the soil can’t be too wet as it doesn’t like wet feet. Blue summer foliage stays blue into September. Zone 4.
Switchgrass (Panicum)
Switchgrass is a native grass found in Ontario meadows. There have been new introductions of switchgrass in the last couple of years which are very exciting to work with. You can’t go wrong with switchgrass, it’s a tough grass and can withstand harsh growing conditions. With the slightest breeze, switchgrass makes a swishing sound in the garden. An upright warm-season grass, meaning it likes warm temperatures to start growing, this grass can be late emerging if we have a cool spring. I would say ‘Heavy Metal’ is my favourite switchgrass though I’ve really like, ‘Northwind’, ‘Purple Tears’ and ‘Cheyenne Sky’ and have been placing them in many garden designs. Switchgrass ranges in height from ‘Cheyenne Sky’ about 3 feet tall to ‘Purple Tears about 4 feet tall to ‘Heavy Metal’ and ‘Northwind’ about 5 feet tall. The taller varieties make great privacy screens, whereas the shorter varieties mix well in a naturalized garden. The foliage of most switchgrasses is grey-green to green in the summer but it’s their fall foliage that is really spectacular. ‘Cheyenne Sky’ and ‘Purple Tears’ fall foliage is bright maroon-red whereas, ‘Heavy Metal’ and ‘Northwind’ turn golden-buttery yellow as temperatures cool. All switchgrass has airy, panicle seed heads and when left standing in winter are an excellent food source for birds. Switchgrass is deer and rabbit resistant. Most switchgrass have an upright habit, grow best in full sun, and require little summer care, once established. Zone 4.
Sedge (Carex)
I really like sedges. These dwarf beauties are perfect for any garden with a bit of shade. A cool-season grass, sedges tend to look great in all seasons, even in the spring after a cold winter. Try ‘Ice Dance’ sedge with its variegated creamy-white margins and deep green centres. It will grow to about 12 inches tall and 18 inches wide. It’s perfect planted in a white flowering garden for a bit of added texture; place ‘Ice Dance’ in with taller hostas and ferns for interest; or tuck sedge in along the edge of an armour stone wall so it can peek out. Mass plant (more than 5 plants together) for the best results. Great as a ground-cover under tall trees. Semi-evergreen. Prune sedges in the spring once the chance of frost has passed and only remove the tips that have winter damage. Don’t trim back too far or you will damage the plant. ‘Ice Dance’ needs a bit of shade from the hot afternoon sun to hold its colour. Provide regular water especially in hot summers. Deer tolerant. Zone 5.
Japanese Forest Grass or Hakone Grass (Hakonechloa)
A handsome grass with arching stems, perfect for a location with morning sun and afternoon shade. If you are looking for a striking grass for your gardens, look no further than Hakone grass. It is not a tall grass, only about 18” tall and wide, however the arching foliage create a feeling of movement in the garden. Perfect for softening the edges of a shaded border, it can be placed in a damp location by the edge of a pond, or a great accent plant in a woodland setting. This grass is slow-growing, so be patient. I have my favourites. ‘Albostrista’ is a dense mound of variegated soft green and white foliage turning to shades of red and purple in the fall. ‘All Gold’ is a dense arching mound of bright yellow foliage with hues of red and purple in fall. ‘Aureola’ has variegated yellow and green foliage, turning red and purple in the fall. Zone 5.
Little Bunny Fountain Grass (Pennisetum ‘Little Bunny’)
Little Bunny is the younger sister of Hameln. A miniature version of the popular fountain grass, Little Bunny grows up to be about 18 inches tall and wide, whereas Hameln will be about 3 feet tall and wide. Both are perfect for a sunny garden as they like full sun and do best there. Pennisetum is a warm season grass so it needs a bit of heat to get started in the spring. Bright green foliage in summer, turns golden yellow in fall. Soft creamy-white bottlebrush flowers bloomin August and persist into the winter. They remind me of soft bunny tails that you just want to touch. This is a great choice for a children’s garden. Place in a border as a hedge with taller plants behind, ideal for placing in a naturalized garden, or plant in mass under taller shrubs or trees. Zone 5.
As you see, there is an ornamental grass for every garden situation. Love them or not, ornamental grasses have become a staple in today’s garden designs.
Enjoy!
Lexi Dearborn
The Gabby Gardener
May 2022