Question
My front and side yard are all asian jasmine.  I would like to put St. Augustine grass in most parts of the yard and leave a small area of jasmine.  I have not had much luck killing it.  What do you recommend?  What time of year should this be done?  Please give me your suggested plan of action.  Thanks.

Answer
Alan,

If I have large areas to kill of anything, and if I have the time, I'll cover it with black plastic in the late spring or summer.  The sun heats up the black surface, and the trapped heat cooks things pretty well.  

If the timing for that isn't right, I spray a broad spectrum (kills everything) herbicide. I use Finale, but there are other brands out there, like Round up.  These work best however, if the plant is actively growing , which again means Spring or Summer.  If a thorough kill is necessary, I would spray the area, wait for the area to die out, then water to encourage growth of anything remaining, including weed seeds, and spray again.  This could take a month.

For what it's worth.
Mark in Portland