I was just curious what weeds have been a problem for your cps, either in pots or in the ground. I grow my Sarracenia in large, undrained pots. I am not sure of the species, but I have a type of fine rush growing in some of them. It grows a large root system and spreads quickly by rhizomes. I don't know if it effects the growth of the plants, but it sure takes over the pot and is difficult to remove.
I also have crabgrass growing in some of my pots, although I have been removing it. Odd that this fast-growing, warm season annual can survive in my lawn when the drought has caused all other grass to brown, and yet also survive in the acidic, water-logged soil of my Sarracenia pots.