This WaPo article by Adrian Higgins about sedges has been going around among my garden-oriented acquaintances, so I thought I’d share my own sedge experiences.
I’ve got two types of sedge in abundance: Carex pensylvanica and Carex flaccosperma. Here is a spot where I’ve got quite a bit of C. pensylvanica:
This started as 3 quart-sized plants about 4-5 years ago and it has spread (and as you’ll see I’ve lifted many chunks of it to other areas of my yard.) It’s planted behind a retaining wall in extremely dry soil in part sun. As you can see in the photo, it does go a bit tawny by the middle of summer, but I don’t mind that. I really like its fine texture and the way it splays. I’ve always had the urge to comb and braid it.
Here’s some more that I transplanted about 2 years ago in attempt to make my ceramic fish look like they’re swimming through a river. It sort of works:
The thrust of Higgins’ article is that sedges make a good alternative mulch, and my experience does bear this out. Before I planted the sedge above, this was an area that I had to weed and mulch to keep looking decent.
Below is a shot taken a bit further up the slope where the sedge has not filled in yet. It doesn’t happen overnight. And you do have to keep weeding and/or mulching during the years that you are waiting for it to fill in.
Here is another spot way in the back of my yard where I transplanted some C. pensylvanica a few years ago. It has spread very nicely. Again, this is dry clay soil, part sun:
I’ve got tons of these garden phlox seedlings all over my yard (the taller pink flowered plant), so I experimented with mixing some of them into the sedge. It’s not bad, but I think a shorter plant might make a better complement.
A word of warning about the idea of sedge as a mulch. It’s definitely not foolproof. I’ve had places where weed seeds had no problem sprouting up through the sedge, and then it’s kind of a nightmare to get them out. For example, this big patch of sedge (above) was pretty infested by some weedy grass last year (maybe stiltgrass?) and I went nuts trying to pull it out. I finally resorted to buying a spray-on grass killer from the nursery; it killed the grass but not the sedge and now this area is pretty weed free.
Here’s another place where I moved some C. pensylvanica:
Again, it’s a place where I use mulch to fill in the gaps around the plants, but you can see that the sedge is starting to fill in those spaces. I was even thinking of planting it in between some of those irises on the right. Irises are a headache for me because weeds appear right down among the plants all tangled up in the rhizomes. I was thinking of trying either the sedge or perhaps Japanese painted fern interplanted with the irises.
Now for the Carex flaccosperma. This is a much coarser sedge with an agreeable blue color that seeds all over the place. Unlike the C. pensylvanica, which spreads via stolons, C. flaccosperma spreads via seeds that pop off in the spring. I have a lot of it an area of my backyard where I am trying to use lots of natives and make a sort of mixed woodland floor type thing:
In the pic above, the C. flaccosperma is the strappy looking plant in the foreground. It’s planted among wood poppies, bluebells, lady ferns, eastern wood ferns, and heucheras. This is my attempt at a “matrix planting” that we hear so much about lately. It has been an interesting experiment.
Here’s another shot of this matrix with the C. flaccosperma visible throughout:
I took this shot today (mid July) but this planting looks best in spring and fall. In spring it has blue bells and wood poppies blooming, and in fall there are many flowers of Heuchera “Autumn Bride” that emerge. The sedge is definitely the background plant that stays more or less constant while the other plants ebb and flow.
But again, the weeds can invade here, too. In the pic above, you can see some dastardly bishop’s weed has snuck in, which is really hard to get rid of. Also, oxalis, crabgrass, and other weeds pop up in there fairly regularly and need to be dealt with.
So it’s not like you can just have this great sedge matrix and then sit in your lawn chair for the rest of your summer. There will always be some maintenance. But yes, it is less work and less money than a sea of mulch, and it is infinitely more interesting to watch it change over the seasons.
It hardly needs mentioning, but of course sedges aren’t the only plant that can act as a living mulch. Behold my Sweetbay magnolia amid a sea of plain green, absolutely indestructible hostas:
Unlike the sedges, once the hostas are filled in there is rarely an issue with weeds. Those wide green leaves pretty much shade out any weed that has the audacity to emerge from the soil. I can move these hostas, hack them in pieces, plop the pieces in a hastily dug holes in some barren part of the yard, and they are sure to survive and cover ground despite my subsequent neglect. They are tough! (I should mention that, sadly, most of the fancy hosta cultivars aren’t this accommodating).
The hosta-scape is functional, but is definitely somewhat static and boring; the sedge matrices I’ve played with are definitely more dynamic and more fun.
I leave you with a non-sedge-related picture of a plant I grow more in love with each year — my bottlebrush buckeye bush, in bloom right now: