Things You'll Need
Rose gloves or heavy-duty leather work gloves
Knockout roses are "self-cleaning," meaning the petals fall off faded blooms while the plant continues to produce flowers. If you don't mind several periods of your rose bush having a slightly scruffy appearance, you can skip deadheading.
Do not compost rose clippings. Fungus, bacteria and insect pests can all hide in healthy-looking clippings. Once composted, these diseases and pests can be spread to the rest of your garden.
Deadheading is a type of pruning where faded blooms are removed from a plant. Plants, particularly roses, are deadheaded to extend the amount of time the plant produces flowers, keep the plant compact and tidy, and stop the plant from producing seeds. Knockout roses are deadheaded to keep the plant looking tidy as this rose produces blooms from mid to late spring through fall even without deadheading. Knockout roses produce flushes of blooms every five to six weeks. Removing faded blooms can decrease the time between bloom production and increase the size and quality of the flowers.
Make a disinfecting/sanitizing solution using bleach and water. Use a 1:10 dilution (1 part bleach to 10 parts water). Mixing the solution in a graded (has units of measurement on the side) bucket makes the solution portable as well as easier to mix. Sterilize your pruning shears in the 1:10 bleach solution between plants. Sterilize your pruning shears between cuts if you have a rose with a fungal or bacterial disease. Dip the cutting blades in the 1:10 solution. Open and close the blades several times while submerged. The blades do not have to dry before you start pruning.
Prune faded and damaged blooms 1/2 to 1 inch above the nearest strong buds (the place where leaves and branches emerge) or branches.
Avoid scratches and scrapes caused by rose thorns by wearing rose gloves or heavy-duty leather work gloves.
Make pruning cuts on a 45-degree angle. The cut should angle away (meaning the short end should be closest to the bud or branch) from the bud or branch.
Either burn deadheaded blooms or place in a trash bag and set out for trash pickup.