Years ago I visited the Scott Arboretum to learn about alternatives to lawn and see the ones they were growing there. (Here’s my 2008 report.) Last month I returned for another event but made time to revisit their lawn-alt plants, too. (Wonder if we can get that term to stick.)
First, the Prairie Dropseed shown above, which my friends at the U.Maryland asked me to inquire about. They want to know if the Scott Arboretum burns it and horticulturist Chuck Hinkle answered, “We burn the sporobolis beds in late winter when the students are on break. The nice thing about it is that it can be done relatively quickly. The grass doesn’t create a huge conflagration (like miscanthus!) and can be controlled easier.” I’ll pass that along, though a non-fire answer was hoped-for (U.Md. isn’t allowed to burn.)
But it’s Carexes I was most interested in checking on. That’s the huge genus, commonly named sedge, that’s so promising as alternatives to lawn in spots that aren’t walked on. At Scott they’ve been growing a wide assortment of them, many of them donated by New Moon Nursery, whose owner James Brown “has been very generous and is trying to promote the use of lawn alternatives,” quoting Chuck.
Above, Carex pensylvanica looking horrible. Here’s Chuck’s explanation: ”The Carex pensylvanica did very well for the first few years. However, as the site became shadier under the maple trees, the plants became thinner. I tried replanting the bare spots but there just wasn’t enough light for them to thrive. So even though they say C. pensylvanica takes shade, I would not recommend it for full shade. You can see areas in the same bed where it gets more light and is more vigorous.”
Below, looking much better.
Above, C. laxiculumus ‘Bunny Blue’ also seems sparse. Chuck wrote that it “also started out pretty well. It started to thin out when I interplanted it with Solidago caesia. Again, I think some of the plants got shaded out. I also heard that some goldenrods are alleopathic so I don’t know if that had anything to do with it.”
Above, C. platyphylla. “The same thing happened with C.platyphylla. It was doing fine until I interplanted it with Allium cernuum.”
Above, C. albicans. ”Carex albicans has been one of the best performers for doing well in a variety of sites – sun/shade,dry/moist,” says Chuck.
Above, the C. texensis looked pretty sparce to me. Chuck says it’s “done well in a drier,sunnier spot. The habit looks a little messy – it flops but has a flat look to it. It self-sows as well.”
Above, C. appalachia.
Overall, Chuck reports that “The growth habits of different species vary greatly. Some of the small clumpers definitely take more time to fill in. C.appalachica,C.eburnea,and C.rosea are slower to fill in. C.sprengellii,C. brevior and C.amphibola filled in very quickly. C. woodii has done well in part shade. It does not like extended dry periods, though.”
And, “Our infiltration beds using carex have generated some interest. We plan on expanding them.”
Two more of my favorites below.
Above, C. leavenworthii.
Above, C. morrowii ‘Silk Tassel.’
UPDATE RE: CAREXES AND SHADE
After reading a comment on an identical post on GardenRant about Carexes and shade, I’ve added two more photos of great Carexes for shade, and will ask Chuck to weigh in on his top recommendations, too. It’s a great group of plants for shade, but some are better than others. (To read that and other helpful comments on this subject, click on that link to GardenRant.)
C. morrowii ‘Ice Dance’ is evergreen, can take sun or shade, is variegated so lights up dark spots, and fills out fast enough to produce plenty of divisions (without spreading thuggishly with runners).
Above, I’ve grown this taller Carex for 25+ years and though I don’t know the name, I recommend looking into it. Evergreen, about 3′ tall, no care required after it’s settled in. Actually, all the Carexes I’ve grown require careful watering after being moved (and preferably not when it’s hot) because their roots aren’t as vigorous as, say, Liriope, which can tolerate any amount of abuse. But at least in their second year in a spot, they’ve required supplemental watering very rarely.
Thanks to Chuck and the Scott Arboretum for their work in trialing and publicizing this important group of plants as lawn alternatives. Posted by Susan Harris.