What Type of Fertilizer Is Best for Knockout Roses?

Knock Out roses are a disease resistant variety of the rose family, hearty in most climates throughout the U.S. and normally blooms every 5 to 6 weeks. A slow release fertilizer is often recommended.

History

Rose breeder William Radler is credited with the development of the Knock Out rose variety. It was a 2000 winner of the All American Rose Selections (AARS) committee.

Types

There are several types of Knock Out roses including the Knock Out, Double Knock Out, Blushing Knock Out, Pink Knock Out and the Rainbow Knock Out.

Fertilizers

According to the Office of Agricultural Communications at Mississippi State University, Horticulturist Norman Winter recommends a feeding every four to six weeks with a slow release fertilizer of 12 to 6 to 6 ratio. The ratio 12 to 6 to 6 refers to the amounts of nitrogen, phosphorus, and phosphate present in the fertilizer.

Care

Knock Out roses fit well into most landscapes and deadheading the old growth of blooms is not required. The roses are considered self-cleaning.

Growth

If left unpruned, the roses may reach approximately 3 to 4 feet wide and 3 to 4 feet tall.

References

• Walter Reeves: History of Knock Out Rose
• Mississippi State University: Office of Agricultural Communications
• University of Missouri: Extension