I said, "Er ... I don't know." Which was kind of embarrassing because I've known about CornWare for months, since ampulets used it at a potluck party.
So the friend --- who barely spends any time online but is always happy to suggest "projects" for my blog --- suggested that I take a (clean) plate home, hang it by the kitchen window and take a photo of it everyday to document its biodegradability.
I took the plate out of my bag last night, but before I did any stringing up today, I checked out the official website FAQ and wouldn't you know it:
4. What are the conditions necessary for CornWare to biodegrade?Perfect for a landfill in Singapore, not so much for the conditions in my apartment, which completely lacks a thin layer of earth.
It will need to be buried under a thin layer of earth and exposed to water and heat for at least 90 days prior to biodegradation.
So much for that experiment idea. But still --- CornWare! You can find it at lots of local chain supermarkets, shelved and priced much like environmentally-unfriendly varieties (ampulets got theirs at an NTUC Fairprice supermarket, for instance). Stock up for your next party or harangue your caterer to get it.
PS: If you're in the US or Canada, you can check out biodegradable cutlery made from potato starch (via Smart People I Know).