Where to Find and Catch Dedenne
From Pokemon Go Wiki
Dedenne are found and captured in Nest and Habitat locations.
Nests
Dedenne Nests are locations that consistently spawn Dedenne.
Habitats
Dedenne Habitats are spawn locations where Dedenne is likely to be encountered, but not guaranteed the way a Nest is.
Additional Tips and Information
Best Nests
If you know a really good nest or any of the nests above is really good, list them here: