Q.How Long After a White Dogwood Tree Is Planted Does It Start Blooming?
We planted a White Dogwood about 2 years ago in our front yard. . . . . . a starter about 3″ tall and it is doing well but it has not bloomed yet. It gets plenty of water and is in full sun.
Certified GKH Gardening Expert
Younger dogwoods will take longer to bloom. normally they need a year or 2 to be mature enough. But you mentioned that it is planted in the yard. If you fertilize the lawn, it is possible the lawn fertilizer is keeping it from blooming. Lawn fertilizer is high in nitrogen, which inhibits flowering.
This article will help as well:
https://www.gardeningknowhow.com/ornamental/trees/dogwood/dogwood-tree-not-flowering.htm