Be prepared to spray regularly to combat rose pests. Spray both sides of the leaves and the stems, using a sprayer that delivers a fine, mist-like spray.
  For aphids, use a systemic rose insecticide. This kills initially by contact and is then absorbed through the leaves and stems into the sap stream of the rose, killing any aphids that suck the sap during the next three to four weeks.
Pests and diseases
Spray with a combined insecticides and fungicides, such as Roseplus, which should be sprayed on to the roses every seven to ten days.
Under glass
Water the path between the greenhouse staging on sunny day, and maintain good ventilation.
  Discontinue feeding when the flower buds start to colour.
  When flowering has finished, move pot roses outdoors and stand them on concrete or stones. Continue watering during dry weather.