If your goal is to transfer all files from
* wildcard does the trick
$ scp ~/local_dir/* email@example.com:/var/www/html/target_dir
-r option means recursively so you must write it when you're trying to transfer an entire dir or dirs.
-r Recursively copy entire directories. Note that scp follows symbolic links encountered in the tree traversal.
So if you have dirs inside
local_dir the last example will only transfer files, but if you set the
-r option, it will transfer files and directories.
Give a try