A folding spray implement for usage in conjunction with an agricultural work vehicle, the folding spray implement comprising: a centerframe assembly; boom assemblies mounted to opposing sides of the centerframe assembly, the boom assemblies comprising: inner wings pivotally joined to the centerframe assembly for rotation about frame-to-wing fold joints; and outer wings pivotally joined to the inner wings for rotation about wing-to-wing fold joints; and an actuation system coupled to the centerframe assembly and to the boom assemblies, characterized in that the actuation system is configured to selectively transition the folding spray implement: (i) from a stowed position in which fold axes of the wing-to-wing fold joints extend principally in horizontal directions; (ii) through an intermediate unfolded position in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and (iii) to a deployed position in which the fold axes of the wing-to-wing fold joints extend principally in horizontal directions, wherein, when transitioning the folding spray implement from the stowed position to the intermediate unfolded position, the actuation system moves the folding spray implement such that: the boom assemblies swing outwardly from the chassis of the agricultural work vehicle by rotation about fold axes of the wing-to-frame fold joints; after the inner wings swing outwardly from the chassis, a lower edge of the centerframe assembly is rotated upwardly in a manner placing the wing-to-wing fold joints in an orientation in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and the boom assemblies unfold by rotation of the outer wings relative to the inner wings about the fold axes of the wing-to-wing fold joints. a centerframe assembly; boom assemblies mounted to opposing sides of the centerframe assembly, the boom assemblies comprising: inner wings pivotally joined to the centerframe assembly for rotation about frame-to-wing fold joints; and outer wings pivotally joined to the inner wings for rotation about wing-to-wing fold joints; and an actuation system coupled to the centerframe assembly and to the boom assemblies, characterized in that the actuation system is configured to selectively transition the folding spray implement: (i) from a stowed position in which fold axes of the wing-to-wing fold joints extend principally in horizontal directions; (ii) through an intermediate unfolded position in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and (iii) to a deployed position in which the fold axes of the wing-to-wing fold joints extend principally in horizontal directions, wherein, when transitioning the folding spray implement from the stowed position to the intermediate unfolded position, the actuation system moves the folding spray implement such that: the boom assemblies swing outwardly from the chassis of the agricultural work vehicle by rotation about fold axes of the wing-to-frame fold joints; after the inner wings swing outwardly from the chassis, a lower edge of the centerframe assembly is rotated upwardly in a manner placing the wing-to-wing fold joints in an orientation in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and the boom assemblies unfold by rotation of the outer wings relative to the inner wings about the fold axes of the wing-to-wing fold joints. inner wings pivotally joined to the centerframe assembly for rotation about frame-to-wing fold joints; and outer wings pivotally joined to the inner wings for rotation about wing-to-wing fold joints; and an actuation system coupled to the centerframe assembly and to the boom assemblies, characterized in that the actuation system is configured to selectively transition the folding spray implement: (i) from a stowed position in which fold axes of the wing-to-wing fold joints extend principally in horizontal directions; (ii) through an intermediate unfolded position in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and (iii) to a deployed position in which the fold axes of the wing-to-wing fold joints extend principally in horizontal directions, wherein, when transitioning the folding spray implement from the stowed position to the intermediate unfolded position, the actuation system moves the folding spray implement such that: the boom assemblies swing outwardly from the chassis of the agricultural work vehicle by rotation about fold axes of the wing-to-frame fold joints; after the inner wings swing outwardly from the chassis, a lower edge of the centerframe assembly is rotated upwardly in a manner placing the wing-to-wing fold joints in an orientation in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and the boom assemblies unfold by rotation of the outer wings relative to the inner wings about the fold axes of the wing-to-wing fold joints. the boom assemblies swing outwardly from the chassis of the agricultural work vehicle by rotation about fold axes of the wing-to-frame fold joints; after the inner wings swing outwardly from the chassis, a lower edge of the centerframe assembly is rotated upwardly in a manner placing the wing-to-wing fold joints in an orientation in which the fold axes of the wing-to-wing fold joints extend principally in vertical directions; and the boom assemblies unfold by rotation of the outer wings relative to the inner wings about the fold axes of the wing-to-wing fold joints.