Clean Saskatoon berries by washing them under running water in a strainer. Remove any dried berries, stems, leaves, debris, and pests.
Add berries to a medium-sized pot and sprinkle with sugar. Add water and bring to a simmer, while crushing the berries with a masher.
When the sugar is completely dissolved, add lemon juice, zest, and vanilla extract. Bring to a boil, then simmer for 20 minutes, or until thickened.
Ladle thickened jam into sterilized jam jars, leaving ¼" headspace. Wipe the rim with a clean kitchen towel or paper towel.
Add lids and collars to the hot water for a minute or two, then add lids to filled jars and hand tighten the collars. Process in boiling water for 15 minutes.
Notes
To test if the jam is thick enough, place a few tablespoons of jam on a small saucer and refrigerate for 10 minutes. This will tell you if it's jelled, or if it needs to cook a little longer.
When serviceberries are in season, freeze them in ziplock bags to enjoy throughout the year.
Saskatoon berries are loaded with vitamins and antioxidants and can be added to shakes and smoothies.
If your berries are nice and big but still not ripe, you can let them ripen on the counter. This is especially helpful when you're worried about birds, bears, deer, and other wildlife eating them before you do.
This recipe can be scaled up or down based on how many berries you have.