The knock out rose is the most popular rose in North America. This rose was bred by William Radler and 250,000 were sold in 2000, the very first year it was introduced. It was also an All American Award winner that year. Since then, the rose has done nothing but grow in popularity, so much so that some gardeners complain the older types of roses are being totally ignored in favor of knockouts.
There are now seven different knockouts which come in several colors and double as well as single blossoms. Each one has several characteristics which were specifically bred into the rose by Radler, whose goal was to make a rose that needed very little maintenance.
Many people think Radler bred this shrub rose so that beginners would have an easier time successfully getting into rose gardening. But that was not his first goal. He bred the knockout roses so that he could grow more and more roses. Normally, roses do require a lot of care. When you have several hundred of them, it takes a huge amount of time to keep up with their needs. The less one-on-one care a rose needs, the more of them you can plant each year.
Knockouts need very little care compared to other species of roses. Let's take a look at some of their advantages:
No demanding soil requirements Knock out roses like well-drained soil the best but that does not mean they will not grow in other types of soils. Make an effort to prepare the soil well when you plant them, and you should have no trouble in getting these roses to thrive.
Choose a good location with at least 4-5 hours of sun per day and a place that is not overly wet. Add 2 inches of compost and some dried manure to the soil when you prepare it for planting.
Pest and disease resistance William Radler bred his knockout species to be exceptionally resistant to diseases and pests. This does not mean your roses will never ever encounter a disease or pest. It means that they are more resistant than any other rose on the market. Knockouts deter pests, even Japanese beetles, who can make a mess of a rose plant in no time.
This landscape rose was also bred to deter blackspot, a problem which faces roses in areas where it is humid, particularly along the Southern and Eastern coast of the United States. With blackspot, the leaves of the rose plant really do develop spots that are round and black.
As this disease spreads from one plant to another, the affected leaves turn yellow and die off. With roses other than knockouts, it takes weekly spraying to keep them free of this and other diseases. And if you do spray with pesticides, you release dangerous chemicals into the environment.
Hardy in cold and heat Perhaps the biggest advantage of the knockout roses is their ability to successfully bloom in areas of severe cold and high heat. Those gardeners who live in the coldest regions, such as USDA zones 4 and 5, or in super hot southern locations, can grow these roses without any kind of bad outcome. They will come back year after year.
Just remember to mulch your knockouts in the summer to keep the ground cool and moist, and in the winter to keep the roots from dying. Knockouts are bred to grow in just about every locale and it does not take a lot of care and maintenance to keep them looking like winners. The best part is they will bloom every 5 to 6 weeks, putting on quite a colorful show from spring to fall.