My solution, working with G+ version "5.3.0.91034052", tested today
final Intent intent = new Intent( Intent.ACTION_VIEW, Uri.parse( "https://plus.google.com/communities/107847486351510098159" ) );
intent.setPackage( "com.google.android.apps.plus" );
if (intent.resolveActivity(getPackageManager()) != null) {
startActivity( intent );
}
It's not bullet proof, you need Google+ app on your device, in case you don't have it some kind of try-catch might be nice (?),