You may find that repotting now will help more than not. Totally replace the potting soil, washing the plants roots well before repotting.

kimmq is kimmsr

Are you speaking of Juncus?

If so, the plant should be cut all the way back to the ground as an annual practice and divided (cut in half through the root mass) before repotting into two containers.

That's just part of the routine maintenance when growing this type of grass/rush in a container.

It's a "Curly Pencil Grass", but I'm not sure if that's the proper name for it. I attach below a photo I've just taken. Notice that even the soil seems to be growing white mould.

Should I control the soil mite / root aphid (?) or should I go ahead and repot? Given the poor state of the plant, is it still a good idea to cut the root mass in half?

Thanks a lot

Will soil mites hurt a plant? I had one plant with them. I think their eggs were in a bag of orchard mix that I used. I did change the soil but I thought they were more of a inconvenience rather than a parasite.

see this http://web.extension.illinois.edu/askextension/thisQuestion.cfm?ThreadID=1543&catID=31&AskSiteID=34 your plant; a rush