January 22, 2010

Tough Plants with Great Texture: Tour of the Scott Arboretum with Bill Costello

Filed under: Garden Lectures — admin @ 10:41 am

Perennial Plant Conference
Friday, October 16, 2009, Swarthmore College

By Susan Haake

It was a cold, rainy day, but the conference was packed with gardeners anxious to learn about the latest and greatest perennials. Not many wanted to venture outside to take the short tour of the courtyard, but I was glad I did. After looking at a thousand photos of perennials, it was nice to get out and actually see them. The focus of the tour was on tough plants with great texture which mostly included grasses, and not the kind you have to mow every weekend. The Scott Arboretum is making an effort to be more sustainable, taking out more lawn and putting in grasses to facilitate drainage. They have several infiltration beds where the water drains into a sistern which collects the water for re-use.

We saw several grasses that were used as groundcovers. The long strands of Japanese Sedge, carex morrowii made for a nice groundcover which had the appearance of waves. It is “evergreen” and has a thin white edges and needs virtually no care; they don’t even mow it. It would be stunning under a stand of birches or a paperbark maple, and likes moist soil and light shade. Prairie Dropseed sporobolus heterolepis, was used in the infiltration beds along the sidewalks and has nice winter interest. Once prairie dropseed is established, it is very low maintenance and even drought tolerant, only needing the dried grass removed once in late winter or early spring. That sure is a lot easier than mowing every weekend. It is a native to Missouri and likes full sun and has a fragrance like cilantro. Blue sedge carex flacca, ‘Blue Zinger’ is a beautiful blue green grass used as a groundcover in the shadier areas around the trees and shrubs. It is about 6-12” high and can grow in diverse habitats and in diverse conditions, but prefers moist soil and light shade. It can take the sun but it bleaches out. Creeping Liriope, liriope spicata created a nice thick mat in areas that needed heavy coverage, but was described as a thug, because of it’s spreading habit. They would mow it down in the spring. liriope muscari was recommended as a better option, having good coverage but being somewhat less aggressive. Japanese Forest Grass hakonechloa macra is all the rage here in NJ, and I always liked the look of it, until my husband, Bob commented that it reminded him of Japanese Stilt Grass. Hakonechloa can be grown in dry soil and part shade and was voted best Perennial by the Perennial Plant Association for 2009.

We saw some ornamental grasses that stood out for there unique texture. Purple Love grass rragrostis spectabilis, is a low growing grass that is nice for the front of borders and has nice fuzzy reddish seedheads, which looked especially nice in the rain. Calamagrostis Stricta was a taller Reed grass (2-3’ high) that provided a nice tall structure behind the Love grass. the Sedge, carex ‘red rooster’, is a native to New Zealand, has a copper color, a fountain-like appearance, and looked nice in a grouping along the boarder, but also does well in containers.

Although I enjoyed the lectures, I think I remembered more from the tour since I could actually see the grasses in the environment, For more information on the grasses at Scott Arboretum, go to www.scottarboretum.org/publications/ornamentalgrasses.pdf YES8254BGJ9V