Answer: Nature Gard for Gardens (page 141 of our catalog) will take care of your corn maggots (as well as many other nasties beneath the soil). So-called bio-degradable pots do, indeed, decompose in the ground. Unfortunately it takes them a lot longer to do so than many people have suggested and often prevents roots from growing out into the surrounding soil. I recommend pulling it up, removing the pot (as you would any nursery container, and replanting the rose.
Q&A Library Searching Tips