If I get something in those cocoa pots, I always remove the pot before planting. Don't even put it in MY compost, but rather the city yard waste.
Talking places NOT to buy hostas, in Canada, Loblaws has a large garden centre and a friend recently bought a plant there with HVX. She tested it to be sure. Canadian Tire regularly has plants with obvious HVX. I would avoid buy hostas at both places.
