We have no convents here.  Lack of vocations.  Our parish does respond to the needs of the outcasts and homeless by means of the St Vincent de Paul where I am an active member.   We visit those in need on a daily basis.  Our parish school has a mini Vinnies where they help the less fortunate.  

Maybe, if the sisters and convents were seen to be helping the needy in the wider community in a relevant way, they might get more vocations from younger women.  Being tied to a charism which is no longer relevant in today's world is why convents seem to be filled with elderly women.