Thursday, May 16, 2013
Patio Update: Controlling crabgrass with corn gluten and establishing creeping and other thymes
This post is an update on the patio and my continued attempts to fight a losing battle with crabgrass. The original post in early April, outlining the problem and last summer's attempts, can be found here.
This year, one new thing I'm trying, after research online, is the application of corn gluten, a naturally occurring pre-emergent. The directions online and on the bag are for application on a lawn, and specify 20 lbs per 1,000 square feet. I don't have 1,000 square feet of patio, and I probably over-applied, putting down about a quarter or a third of a 25 lb. bag and then sweeping it into the cracks. The result, on April 10, was:
The yellow substance is the corn gluten.
Now, corn gluten is also heavy in nitrogen, so one of the immediate effects was to green up the existing weeds. Great!
I also went out to the local nursery, as we got closer to last frost date, and bought a little group of groundcovers that are designed for pathways. Most of these are creeping thymes. There are a dozen species, and I will try as many as I can. There are also a couple of other species that will live with shade, that are not thyme. Putting these in will create my second line of defense, over time. Or that's the theory anyway.
This past weekend, the crabgrass germinated, right on time, just as the lilacs across the street began blooming. The tiniest blades popped up on May 10. And on Saturday, I spent about a half hour picking eensy-weensy crabgrass seedlings out of the patio. There are definitely many, many fewer crabgrass seedlings, so far, than there were last year. Last year the patio was covered with 100's and 1,000's of seedlings and it would have literally been impossible to pull them all. This seems more doable, so I pulled every seedling I saw. Let me tell you, it is definitely easier to pull a seedling in May than an established plant in July or August.
And, this is what the patio looks like presently. I've been gentle on the existing weeds, which have flourished because of the nitrogen in the corn gluten. But most other weeds, in the end, are much easier to pull than crabgrass, so for this summer and until my creeping thymes get established, I have also decided to view other weeds as my allies, as they will crowd out any crabgrass seedlings.
Except mugwort, which is totally invasive, and I pull every tiniest bit of it I see every time I cross the patio.
It's not really where I want it to be yet, so, a definitely a work in progress.
In any case, the bits of creeping thyme and elfin thyme I planted last year have survived. Some have grown only modestly, and others have thrived. Elfin thyme is a much slower, lower grower, but in areas of high traffic, I think it will do better.
Here is a bit of elfin thyme that has grown by about 300 percent, I'd say:
Here, a elfin thyme bit that only barely managed to survive the winter and has not grown at all:
Here is a bit of creeping thyme that has flourished and has grown nearly around the perimeter of an entire brick:
And here, along the line of bricks at the top, more creeping thyme that has grown horizontally across four bricks and down between them in three little advancing forays, like a 3-legged F turned over, crouching on its little legs.
Creeping thyme is definitely a much more aggressive grower, quicker to establish itself across a larger area. It also grows across bricks, seen here below, which I haven't yet seen any of the mint thyme do.
And, in one of the places where the spring rains collect, irish moss. That will dry up as we get into summer.
Here, in the wet shady end of the patio, a naturally occurring shade ground cover:
And, another, that I planted last year, pale green leaves coming up from last's years dead leaves. I don't know if this will be evergreen or not on the patio. I also planted it near the downspout in the well garden, and there it stayed green throughout the winter.
And, a weed that I ordinarily would completely rip out -- clover -- but it's naturalized so well, I am going to try leaving it as part of my defense against the crabgrass, for this year anyway. I may rue that decision, because clover can be very hard to get out entirely ...
And, last but not least, song sparrow, at the bird feeder ... one of the reasons I don't use herbicides. There seem to be two males in my yard this year, singing away every morning. So beautiful.