Q. What is the proper layout of drip line irrigation for rose bushes?
Thank you for your question about drip irrigation. See link below. Roses need watering usually once a week. More on the how to below.
Here's the pros and cons and how tos of drip irrigation: http://extension.colostate.edu/topic-areas/yard-garden/drip-irrigation-home-gardens-4-702/
All about "Watering Roses" is completely discussed below from American Rose Society.http://www.rose.org/rose-care-articles/watering-your-roses/
Hope this helps.