Cutting Knockout Roses Too Soon

Yearly Pruning

• Knockout roses are pruned when they are three years old, or older. After the initial pruning the bushes do well when pruned at three year intervals.Normally, roses can take up to two years to bloom. Pruning a young shrub rose too early in its life will result in an additional season without blooms. Allow the plant to mature and develop before cutting back its branches. Some rose gardeners find it necessary to prune back knockout rose bushes each year, rather than every three years. The bush is a rapid grower. Cutting back the bush annually controls its vigor but does not reduce it.

Seasonal Pruning

• Knockout rose bushes are pruned in early spring. Early spring pruning encourages new growth. This new growth produces buds. Once the buds flower and ultimately die, knockout roses continue growing and producing new buds and flowers until the first frost. Roses that bloom this way are referred to as repeat bloomers. Cutting back repeat bloomers will result in smaller blooms but will not cause the bush not to blossom. The danger of pruning a knockout rose bush too early is not due to its appearance but rather, to its health. Rose bush canes are sensitive to frost and cold. Cutting canes early, before the frost danger has passed, exposes canes to frost injury before the wounds have a chance to heal over. If you have cut your knockout roses' canes and they have suffered frost damage be certain to inspect the canes and remove those that have turned black or appear severely damaged.

Pruning Techniques

• Even if you have cutback your knockout rose bush too soon damage will be less severe if you've used proper pruning techniques. Prune canes with scissor-like clippers rather than anvil-style clippers. The latter type tend to crush canes rather than cutting them cleanly. Inspect canes prior to clipping, and after. When a cut cane's interior is soft, hollow or a color other than white then the cane is not healthy. Cut it back until you reach healthy wood. Make your cuts 1/4 inch above a bud and angled in the same direction as the bud. This kind of cut encourages new growth.

Considerations

• Protect your knockout rose bush from frost by covering it in loose burlap. Set up a wire partition around the perimeter of the bush, place loose leaves or straw within the partition and cover. This will prevent frost injury whether or not you have pruned your bush too early in the season. If the diameter of a cane is wider than your smallest finger then seal the wound with clear nail polish or wood glue to prevent insect infestations.