The ornamental design for a floral merchandiser display stand, as shown and described.
FIG. 1 is a perspective view of a floral merchandiser display stand showing my new design, with floral containers and hanger units being shown in broken lines and not forming a part of the claimed design.
FIG. 2 is a top plan view thereof.
FIG. 3 is a front elevational view thereof.
FIG. 4 is a left side elevational view thereof; and,