hb = boxplot(1:10,[zeros(1,5) ones(1,5)], 'colorgroup', [0 1], 'colors', 'rb', 'orientation', 'horizontal');
Get each graphics object's handle (second column is second box) and set its 'YData' to be the former ydata I the index
for ii = 1:size(hb,1)-1
set(hb(ii,2),'YData',get(hb(ii,2),'YData')-1)
end
This would extend as the number of boxes grows too.
