Before adding anything to a new rose bed, I suggest getting a professional soil sample (I just sent mine in to the Univ. Ext.---$15 for basic + $6 for Ca, Mg & S)The most important thing you want to do first is adjust pH (6.0-6.5 for roses)because this is what makes your fertilizer available to the roses. The second thing I would add to a new rose bed is organic matter---as much as you can. This should take care of all your micronutrients plus build good tilth in your soil. Then take a look at the P & K recommendations from your soil test---if you need P, add some bone meal, or super phosphate in the bed & if you need K, add some green sand or wood ashes. For a more complete view of soils, ph,& fertilizer I would suggest a book "Secrets to Great Soil" by Elizabeth Stell.
ECWIRoseman