KnockOut roses are engineered to be low-maintenance, disease-resistant and vigorously blooming. The KnockOut rose bush blooms from spring until the first frost in fall, requiring little pruning or care. This rose variety reblooms every five or six weeks throughout the growing season. KnockOut roses are also rather heat- and cold-tolerant, growing in regions where winter temperatures dip down as low as -15 degrees Fahrenheit. The KnockOut rose bush can grow to 3 or 4 feet tall and wide, with a wide range of available flower colors.
Water your KnockOut roses deeply two or three times a week during the summer and once or twice a week during the spring and early autumn. Don't allow the KnockOut rose bushes to dry out between waterings.
Feed your KnockOut rose bushes once each month during the growing season with an all-purpose rose fertilizer. Follow the fertilizer dosage instructions on the label.
Cut your KnockOut rose shrub back to about 1 to 1 1/2 feet above the ground in early spring, after the last hard frost. If the rose bush is larger, simply cut it back to about one-third or half its height.
Trim your KnockOut roses in the springtime to shape the bushes and remove any diseased, damaged or dead growth. Unlike other rose bush varieties, the KnockOut rose requires very minimal pruning.