Roses and Yews
Will knockout roses planted in front of a hedge of yews flourish? The roses would be on the east side of the yews.
I would think that if you leave two to three feet between them, they should do fine. I say to leave 2 to 3 feet to allow both room to fill in half the area between them with foliage. That distance will hopefully allow for the nice filling out growth and allow good air movement through both of them so that no funguses get any ideas of attacking them.