Image by Tony Alter
By Stan V. Griep
American Rose Society Certified Consulting Rosarian – Rocky Mountain District
Rose Breeder, Bill Radler, created the knockout rose bush. It was a big hit, too, as it was a 2,000 AARS and smashed the record for sales of a new rose. The Knock Out® rose bush is one of the most popular roses in North America, as it continues to sell very well. Let’s look at how to care for knockout roses.
Care of Knockout Roses
The Knock Out® roses are easy to grow, not requiring much care. They are also very disease resistant, too, which adds to their appeal. Their bloom cycle is about every 5 to 6 weeks. The knockout roses are known as “self-cleaning” roses, so there is no real need to deadhead them. Several knockout rose bushes blooming along a fence line or at the edge of an island landscaping is a beautiful sight to behold.
Although knockout roses are hardy to USDA Zone 5, but they will need some winter protection. They are extremely heat tolerant, thus they will do well in the most sunny and hot of locations.
When it comes to growing knockout roses, they can pretty much be listed as plant them and forget them roses. If they do get a little out of the shape you like for them along your fence line or garden edge, a quick trimming here and there and they are right back to the form you like blooming all the while.
If no rose bush forming pruning is done to adjust their height and/or width, the knockout roses can reach 3 to 4 feet wide and 3 to 4 feet tall. In some areas, an early spring pruning 12 to 18 inches above the ground works well, while in areas with harder winters they may be pruned down to around 3 inches above the ground to remove the dieback of the canes. A good early spring pruning is highly recommended to help get the top performance out of these fine shrub rose bushes.
When caring for knockout roses, feeding them a good organic or chemical granular rose food for their first spring feeding is recommended to get them off to a good start. Foliar feedings from then on until the last feeding of the season works just fine to keep them well fed, happy and blooming. Without a doubt there will be more and more rose bushes added to the knockout family of rose bushes as research and development continues. Some of the current family members are:
- Knock Out® Rose
- Double Knock Out® Rose
- Pink Knock Out® Rose
- Pink Double Knock Out® Rose
- Rainbow Knock Out® Rose
- Blushing Knock Out® Rose
- Sunny Knock Out® Rose
Again, the knockout line of rose bushes is bred to be a low maintenance and low need for care rose bush.