Are you unable to put your elm outside? Outside is always better than inside.
Search the forum for "grow light" and "growing light" to see what information you can find that has already been discussed. There have been some very good threads in the past about growing indoors. Humidity is also an issue indoors, so you need to look into that as well.
Search in particular for post by Carl Rosner and Jerry Meislik, both of whom have had a lot of success with indoor growing.
Joanie