The simple answer is yes. However, make sure not to begin painting until 4-6 weeks has passed, otherwise, you may damage the work done on your house.  A couple of things to bear in mind:  Ensure that the surface of your roughcast is clean and free of dirt, dust, algae and mould. For older roughcast surfaces, you may need to order an inspection to be done to see if any repairs need to be made.  Use a primer designed for masonry surfaces, as this will help the paint adhere better to the roughcast and give a more even finish to the wall. Drying time differs, so ensure you consult the manufacturer’s instructions.  Apply paint using a brush, roller or spray. You may need multiple coats to get the desired results.