Jennifer Schultz Nelson
Extension Educator, Horticulture
Every gardener I know, at one time or another, has inadvertently planted a thug in the garden. By thug I mean a plant that takes over the garden, bullying its way over every other plant that's already there.
Some ornamental grasses are incredible bullies in the garden. Grasses will tend to grow in two ways-- as clumps that get thicker and wider, or as a spreading mass which sends out rhizomes or stolons to colonize any available ground.
Clumping type grasses are welcome occupants of a perennial border, because they are polite and stay in the place you put them. But spreading type grasses are usually rude guests in the perennial garden. They spread quickly via rhizomes. Left unchecked, in a season or two they would crowd out everything around them. This trait can be used to your advantage if you are trying to reduce erosion on a hillside for instance. Rhizomes in a spreading grass will interlace and physically hold the soil in place.
I've avoided planting grasses that spread, for fear they will be a nightmare to control. This past spring I was at a seminar where the speaker declared her disdain for just about every ornamental grass in existence because she felt they were way too aggressive in the garden. There was one exception to her rule: Golden Hakone grass.
Golden Hakone grass, Hakonechloa macra 'Aureola' is also called Golden Japanese Forest Grass. It is native to Honshu Island, Japan. It is a spreading grass, but slow growing. As an added bonus, it is also one of the few ornamental grasses that likes partial shade. It was named 2009 Perennial of the Year by the Perennial Plant Association.
Standing at only 12 to 18 inches tall and 18 to 24 inches wide at mature size, Golden Hakone grass is a small but mighty member of the garden. Each blade of this grass is about half an inch wide, bright yellow in color, and edged in a green stripe. As the weather cools down during Autumn, the grass takes on a pinkish red color.
Golden Hakone grass tends to grow arched over to one side. In a large planting the overall effect resembles waves or a waterfall. Some have described it as looking like a cascading miniature bamboo.
Hardy in Zones 5 through 9, Golden Hakone grass is hardy in most of Illinois. A couple of inches of mulch applied after the ground freezes in winter will reportedly enhance overwintering success.
Soils that are well-drained, rich and loamy are best for Golden Hakone grass. Unfortunately, excessively sandy or clay-filled soils are not the best choice for this plant.
One of the more unusual attributes that makes this grass very versatile in the garden is it not only tolerates, but it actually prefers partial shade (4-6 hours direct sun). Most grasses need full sun (6+ hours direct sun). In full sun, Golden Hakone grass will scorch and burn. In deep shade (<4 hours direct sun), this grass will appear more lime green in color rather than golden. Partial shade will bring out the best in Golden Hakone grass.
Just when I thought this plant couldn't get any better, I noted that most descriptions of Golden Hakone grass list it as deer resistant. Living in an area where deer are a nuisance, this added feature is a real bonus.
Other cultivars of Hakonechloa macra available include:
· 'Beni-kaze' (translated as 'Red Wind' in Japanese)—solid green blades turn bright red in fall
· 'Naomi'—solid green blades turn reddish-purple in fall
· 'Nicholas'—solid green blades turn orange-red in fall
· 'Sunny Delight'—green blades streaked with yellow
· 'Albo-striata', 'Fubuki'—green blades striped with white
· 'All Gold'—golden yellow blades