Porkpal said: "I am never sure why some cuttings take and others don't."
I am new to all this so I can only guess. I wonder if it has something to do with the time of the year (Spring vs. Fall) the cutting is taken. OR from the type of climate it was originally hybridized??? Perhaps some of these roses are difficult to root because they are genetically weak and should never be own root roses. Maybe after they made their crosses years ago, they automatically grafted them all rather than risk poor performance.