Question
Zone 5 - Chicago IL.  Planting KOR in an area with a rather shallow clay base.  Not much topsoil.  I am going to dig rather large holes to remove clay and fill in with new soil/compost, etc.  What compost or poting soil and fertilizer mixture will work to help them growth the best?  Any planting tips appreciated as this is the first time.

Thanks

Answer
For clay so if you dig the hole 2 feet wide and if possible 2 feet deep or at lest 18 inches deep that will be large enough for a mature rose. Mix i/3 of your clay soil with 1/3 compost, bark mulch (fine ground) or a bag of steer manure and 1/3 potting soil, the roses will do really well. Roses don't use all of the hole. They use the top 12 inches most as many of the feeder roots are up there and the other roots are anchors. So sprinkle some rose fertilizer all around the base of the rose bush and if possible use some mulch around the base too as roses love cool, damp roots and the mulch will give them that. Knock Out roses are easy to grow so you should have no problems as they will love your clay soil.