After I posted about starting my own sweet potato starts last week, my fabulous neighber Alexia posted a great link to my fb timeline.http://wakeup-world.com/2012/10/15/16-foods-thatll-re-grow-from-kitchen-scraps/
Thank you, Alexia!
The timing was fortuitous because earlier in the week I had remember reading somewhere that you can grow new leeks by planting the roots that you cut off the ones you get at the store. I thought I'd try it since I haven't been able to grow leeks from seed here yet. So we bought some leeks, made some potato leek soup and stuck the root ends in some water to see what would happen. Green happened. Within just a couple of days, the centers started swelling and turning green.
When they got a bit bigger, I stuck them in soil in a milk jug and put that in the hoop house so they can have as much sun as possible.
Hopefully we'll have some good leeks this year.
Take a look at that list of veggies in the top link for more food that you can easily grow from kitchen scraps.