They are spreading naturally but nowhere near the height yours are. Yours are massive! Mine are more like just 1 plant here and there.
The past 2 Winters have our flowers acting like they are in a sub tropical zone. Very few blooms and my Irisis's have been destroyed aka@ eatin" :mad".....by squirrels and chipmunks.
I have what i nicked named a "frankenwood" dogwood. IT is a graphed American white dogwood with a Japanese Kusa dogwood. It is about 20 years old. After about 10 years the center root began blooming white in May...then the outer graph blooms a "light green" flower then it turns white in late May-June.
Go figure!
Dan
