Care and feeding
Newly planted bare-root roses should not be fertilized until they have leaves along all their canes, four to six weeks after planting. Pot-grown roses with some leaves, however, can be given a light feeding or half-ration of fertilizer at planting.
Established roses are heavy feeders. Provide a granular or liquid rose food (follow package directions) soon after buds break and leaves appear on the canes. Apply fertilizer a second time just as the first flush of flowers is finishing in early summer. A third application of fertilizer should be made no later than July 30.
To prevent blackspot and mildew on leaves, spray them every seven days with a solution of 1 tbsp. (15 mL) baking soda and 2 tbsp. (30 mL) commercial horticultural oil (available at garden centres), mixed into 1 gallon (4 litres) of water.
Photo: 'Francine Austin'