Grass growing in ground cover

I have a problem with my nearly 2 year old Blue Star Creeper. Blue Star is a very pretty low growing ground cover that blooms late spring and early summer. I have a fairly large area of it in my front yard. My problem is that I have wild grasses growing in it that are actually squeezing the Blue Star out. It is impossible to pull the grass out without pulling the Blue Star out with it. It won't be long, and I will have to mow it!
I live in the Seattle Washington area.
Does anyone know of a product that will just kill the grass and not the ground cover?
Tom

The only thing I know that you can do is to take a small paint brush and paint the grass with roundup. Is the problem way to big for that?

Smokey

I think there might be some herbicides that will kill grass but not broadleaf plants. I always hand pull weeds so I don't know any brands or anything, but if you go to your local home center and look at the labels on the herbicides if it only kills grass it ought to be pretty clear from reading the label. Or if you hand pull, some of the BSC will come up with it, but it should grow back and fill in again, so that might be an option.

Thanks for the replies.
I've tried painting the roundup method, too much grass.
Generally I like to pull the weeds too. However I would have to pull just about all of the BSC in order to get to the grass (very dense).

Has anyone heard of a product called Poast Grass Killer? I found it online, I think from a company in Canada. It's kinda expensive and mail order only, so I'm skeptical.
Tom

Here are a couple US based sources http://www.greenwoodnursery.com/page.cfm/12369 and http://www.bugspray.com/catalog/products/page2004.html There are probably others as well--I had put it into Google because I was going to see if I could find any info on it, and these were some of the first things that popped up. The first link says Poast is an old name and now it's called Grass Getter so you might try googling that too.

I have had a similar problem and ended up having to dig out the ground cover in chunks to make it easier to get the grass out and the put the ground cover back in place. It is slow going, but it works. If you do that remember to give the replanted ground cover lots of water for awhile.

Some of the big box stores carry a product called 'Grass Out' by Ortho, but, I haven't noticed it lately. If you do try a selective chemical, test a small area first to make sure it won't damage the Creeper. Always read and follow the directions, more is not always better and sometimes there are products that shouldn't be used during periods of high temps. And for the future you might want to consider a Pre-emergent, but, with all the rain you get in the NW that may not be practical.

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