Knock Out® Rose
A 2000 AARS Winner that needs only half a day of sun!
Plant Patent #11,836. Cultivar name: 'Radrazz'. Perhaps the best-ever landscape Rose for four-season interest, this stunning hybrid is the culmination of breeder William Radler's lifework. Not only is it the most blackspot-resistant Rose we've ever grown, but it also stands up to Japanese beetles and other pests, needs only half a day of sunshine, blooms over an exceptionally long period, and offers foliage and fruit interest as well as lovely blossoms.
Exceptionally hardy and disease resistant, Knock Out® is also breathtakingly beautiful, with great clusters of 3 1/2-inch blooms of fire-engine red (or lighter cherry-scarlet in hot climes). These flowers begin early in Rose season and continue for many weeks. The shrub then rests for a bit and repeats for the remainder of summer and well into fall! It's one of the longest bloom cycles in the Rose family and will fill your garden with bright color and subtle tea scent. And when the blooms finally end, the color continues with burgundy-violet fall foliage and orange-red hips.
Crown hardy to -20°F, this 3- by 3-foot shrub sneers at drought, humidity, and pests such as blackspot, Japanese beetles, leafhoppers, and rose midge. It is essentially maintenance free, although like any new addition to your garden, it appreciates pampering the first season or two. Knock Out® was bred from a seedling of R. 'Carefree Beauty' x a seedling of R. 'Razzle Dazzle'. It has become so immensely popular since its introduction that new Knock Outs® are arising each season. We recommend Pink Knock Out® and Double Knock Out®.
Knock Out® never needs deadheading and is one of the very few Roses that earns the title "maintenance free." Zones 4-9.
| Genus | Rosa |
| Variety | Knock Out® PP#11,836 |
| PPAF | PP#11,836 |
| Bloom Season | Early Summer - Mid Fall |
| Habit | Compact |
| Zone | 4 - 9 |
| Plant Height | 3 ft |
| Plant Width | 3 ft |
| Bloom Size | 3 in - 3.5 in |
| Item Form | Bareroot |
Additional pruning tips for healthy, beautiful, productive roses:- Whether you’re deadheading, removing dead wood, or performing an annual pruning, make sure your cuts are no more than ¼ inch (5 mm) above a bud, and slope the cut away from the bud, to prevent water from collecting on it.
- Your cuts should always be clean, so keep your pruning shears sharp, and use pruning tools that are appropriately sized to whatever size stems you are cutting.
- To encourage an open-centered form, cut to an outward-facing bud. To encourage upright growth on roses with a spreading habit, prune a few of the stems to inward-facing buds.
- Prune any dieback to the healthy, white pith.
- Remove dead or diseased stems, as well as any that cross or are spindly.
- Your goal should be to have well-spaced stems that allow for a free flow of air.
- If pruning an established plant, remove any old wood that is flowering poorly, and use a saw to get rid of old stubs that are no longer producing new shoots.
- Other than climbing roses, you should prune newly planted roses hard, which encourages vigorous shoot production.
- When removing suckers, trace them back to the roots from which they are growing, and simply take them off.
- Butterflies like a lot of sunlight, so locate your garden in a sunny area.
- If you live in a windy location, plant your butterfly-attracting plants near a building, fence, or hedge to protect them.
- Plant a variety of nectar-rich plants, as well as shrubs and evergreens for shelter.
- Since many butterflies and native flowering plants have co-evolved, try to put in some that are native to your area. The Lady Bird Johnson Wildlife Center provides lists of plants native to states and regions.
- Certain colors are particularly attracting to butterflies – red, yellow, pink, purple, or orange blooms that are clustered or flat-topped, with a short flower tubes are especially attractive to adult butterflies.
- Avoid using pesticides, especially around nectar-producing plants.
- Provide a shallow source of water – try a birdbath with pebbles lining the bowl.
- Place a rock in a sunny spot for butterfly basking and resting.
- Create a "puddling area" by digging a shallow hole filled with compost or manure where rainwater will collect and release essential salts and minerals.
- If you want butterflies to breed in your garden, put in some caterpillar food plants, such as parsley, milkweeds, asters, thistles, violets, clover, grasses, and Queen Anne’s Lace.
- Since butterflies need nectar throughout the entire adult phase of their lives, try to create a design that will allow for a continuous bloom – when one stops blooming, another starts.









