I don’t always use every last bit of fresh produce that I have, so I freeze things!
The best way to freeze things so they don’t glom together is to add your blueberries, green onions, peas, etc. in a single layer to a baking sheet. Try to keep them as separated, but some can touch. Just keep them in one layer.
Put them level in the freezer. Wait.
Once they’re frozen, remove them from the baking sheet and put them in a freezer bag or other container. Now, when you go to use a little here or a little there you’ll have single pieces instead of a chunk of raspberries or a icy ball of peas.