Preheat oven to 325°. Remove Mayfield lemon ice cream from freezer to allow it to soften slightly.
In a medium-size bowl, combine graham cracker and sugar. Add the butter and combine. Press the mixture evenly into the bottom and sides of the pie plate. Bake at 325F for 8-12 minutes or until golden brown.
Remove and allow to cool on a wire rack until cool enough to handle the pie plate, about 10 to 15 minutes.
Place the pie plate in the freezer and allow to chill until cold to the touch, another 15-30 minutes.
When the graham cracker crust is cold, make the filling.
In a metal bowl, fold together the softened ice cream with 1 cup raspberries and 1 cup of the blackberries (halved) using a rubber spatula.
Allow the berries to evenly distribute into the ice cream.
Spoon the pie filling into the pie crust and spread it out in an even layer. Place in the freezer.
When you are ready to serve, Spread an even layer of whipped cream over the pie filling and top with as many berries as will fit.
If the pie is still very cold and stiff, place in the refrigerator for about 10 minutes for easier serving.