Grass or sedge in CP container

I started a small (oh 3 foot by 1 foot or so) container of sarracenia, drosera, and VFTs about 15 months ago, everything doing pretty good with full time outside...however...
Oh my, the little green grassy things are pretty much all over. I assume the best thing I can do it try to pull them out as soon as possible? I don't think the competition would be favorable on esp on the tiny drosera and the flat growing VFTs. Since I mow around it...I didn't even know that seed had fallen into it..but geez, so many.
Any advise?
The seeds probably came from the medium used, and either grasses or sedges will fill the soil with roots and can strangle the other plants in some cases, or just be a pain to remove when they establish.