Purple plums, yellow plums, Italian plums. All types of plums are good for canning! Some are a little sweeter, and some have a little more tart flavor, but they are all very similar. Wild plums and damsons are really easy to pit while whole with a cherry pitter, while others you have to cut in half to remove it. The least expensive plums are at the peak of the season when there are more available, although I'm always waiting impatiently for harvest season to start.