In a small bowl, submerge the raisins in boiling water. Let them sit for 15 minutes to rehydrate and plump up. Drain and place in a medium bowl
Add the yogurt, cucumber, herbs, garlic, walnuts, olive oil, and salt. Stir to combine, taste, and adjust salt as needed.
Chill until serving. If desired, garnish with crumbled rose petals before serving.
Cover and refrigerate leftovers for up to 3 days