What is the ruling on hanging flowers around the neck as a greeting to newcomers?

If kissing the hand is a common custom in some Muslim countries, then there is no harm in it, God willing, provided that it is not a substitute for saying salam. However, if it is done in imitation of disbelievers, then it is not permissible, because imitating them is prohibited. The same applies if it is done as an act of worship or as a replacement for saying salam.