I have a 10 year old flowering Dogwood–a Cornus Kousa— and it is now mid-May. There is no sign of flowers just short pointy pieces at the end of each branch. There are many of them and I broke one off and it’s green underneath. Is it just that these shrubs are quite behind or does the shrub have another problem?
Due to our extremely cold, long winter and cool spring, everything seems to be late this year, so I think you should just be patient. Your Cornus kousa is not usually susceptible to serious insect or disease problems, and is cold hardy so likely did well through our abnormally cold and long winter season. The tree usually blooms in May or June; it sounds as though it’s just taking its time.
Here is an article on the Dogwood from the Clemson Cooperative Extension, which highlights the fact that the Kousa dogwood flowers a few weeks after the flowering dogwood (Cornus florida). As I’ve just started to notice these latter trees flowering in my mid-town Toronto neighbourhood, I have a feeling it will be a few weeks longer before your tree decides to bloom
Missouri Botanical Garden. Cornus kousa. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=j910
Ohio State University. Cornus kousa.https://hvp.osu.edu/pocketgardener/source/description/co_kousa.html “…vegetative buds are thin and conical, while the floral buds are pointed and oval, with the two floral bud scales slightly separated at the edge of the bud”