Working in the produce business, the most common question I get it (besides where is the bathroom) is when is this piece of fruit going to be ripe. Some fruit that is easier to do. Plums and their pluot or plumcot offspring can be difficult for people to figure out when they are best. Unlike peaches, plums don't get to the gentle pressure that a peach does when ripe. Instead you are looking for a plum's skin to wrinkle when ripe. But when you know you have a truly ripe and delicious plum is when it fills heavy for it's weight. It should feel like holding a water balloon in your hands. If you can be patient and wait until the plum is that ripe, you will be rewarded with the most juicy-sweet plum experience you can get.
Want to learn more about plums? Check out my post on when plums are in season.
Also check out my recipe for Spicy Plum Glazed Pork Tenderloin. It's another way to use plums that you may not have thought of it before and it's delicious!