Most likely a dry method.Brush Pro Dry Powder is a good option. Encapuclean with a CRB or on a bonnet is another choice. Consider soil level, soil type and how moisture would affect the edge binding. Also on location or in plant as Mikey asked.
If it is smaller and you can get it evenly damp and evenly dry with no boundary or interface between a dry area and a wet area (where water stains can form), then you can HWE with a low moisture tool.