- 3 cups blackberries
- 1 cup raspberries
- 1/2 cup simple syrup
- 1/2 cup white grape juice
- 1/3 cup freshly squeezed lemon juice
- Ice, for serving (optional)
- Seltzer or sparkling wine, chilled
- Patriotic fruit skewers, for garnish (optional)
Place blackberries, raspberries, simple syrup, grape juice, and lemon juice in the jar of a blender; puree until smooth. Strain mixture through a fine mesh sieve, discarding solids.
Fill 8 Collins glasses with ice, if using. Divide mixture evenly between glasses; top with seltzer or wine and serve immediately garnished with fruit skewers, if desired.