Knockout roses are popular perennial shrubs valued for their drought tolerance, abundant flowering and relatively low maintenance requirements. The plants bloom from spring until the first frost of winter, producing a new batch of flowers once every five to six weeks. The pink flowers are self-cleaning, which means deadheading is not required. Knockout roses typically reach 3 to 4 feet in height with an equal spread and perform well in perennial borders. Purchase container-grown Knockout roses from your local garden center and plant as soon as possible for the best results.
Choose a planting site for Knockout roses that receives five to six hours of full sunlight throughout the day and consists of well-drained, moist, fertile soil. Perform planting during mid-spring, after all danger of frost has passed in your area.
Spread a 2-inch layer of peat moss over the planting site and use a garden tiller to amend the soil, increasing both fertility and drainage. Dig a hole in the soil twice as wide and twice as deep as the plant's current container.
Water the plant thoroughly, remove from the container and gently loosen the roots with your hands. Insert the root system into the hole and backfill with soil. Soak the soil thoroughly to bring moisture into contact with the roots. Space Knockout roses 3 to 4 feet apart.
Spread a 2- to 3-inch layer of mulch over the soil surrounding Knockout roses to provide insulation, deter weeds and increase moisture retention. Allow at least 4 inches between the mulch layer and the crown of the plant to provide air circulation.
Check the plant every one to two days for the next two to three weeks to ensure it is adjusting to its new location. Water once every five to seven days to prevent the soil from drying out completely. Fertilize lightly with a 10-10-10 NPK fertilizer if the foliage begins to yellow or drop. Apply at the rate recommended by the manufacturer for the best results.