Rose Feeding: Roses are heavy feeders and thrive on frequent but light applications of fertilizer. For a basic fertilizing program, during the regular growing season, from March through October, feed every two weeks with a complete rose fertilizer giving each bush 1/4 to 1/2 cup spread evenly around the bush from the shank to out past the drip line. (I do not recommend one that contains a systemic insecticide). An alternate, more organic method of fertilizing is given below.
MY BASIC FEEDING PLAN — First and foremost make sure your pH is in the desired range (5.7 – 6.5) and adjust if necessary. If the pH is not in the proper range, fertilizers will not be absorbed correctly by the rose bushes. Some elements may be too available, others not available in adequate quanti- ties. My current fertilizer program is based on 10 years of soil reports. The basic program is outlined below. This calls for feeding the roses two times each month – March thru October – and one time each month the rest of the year.    The start date is based on the spring pruning date – (below is based on pruning around the end of February/beginning of March).

Orlando Knockout Roses

Orlando Red Roses