Rinse & drain the wheatberries
Put water in a large saucepan and bring to a boil.
Add the wheat berries to the boiling water, then reduce heat and simmer for ~ 1 hour. The wheat berries are done when they have a chewy texture. Once cooked, drain and cool.
While the wheat berries are boiling, chop the celery, parsley, scallions (or green onion) and the walnuts. Combine those in a large bowl and set aside.
In a separate bowl, combine the oil, lemon juice and salt. Set aside.
Once the wheat berries are cooked and chilled, add the celery, scallions, parsley and walnuts, then add the oil and lemon juice mixture. Stir until all of the ingredients are well combined.
Gently stir in the blueberries, then cover and refrigerate to chill.