Worth a repeat visit

     Last year I posted about my favorite shrub, Spiraea fritschiana, or Korean Spirea.  This year I got some better photos, so I thought it deserved a repeat appearance.
     Michael Dirr, the best authority, says it is "virtually unknown in the United States.  Indeed, I have only seen it twice outside my gardens.  I used to grow it when I was in the nursery business many years ago.  Neither of us can figure out why it is not more common.