How to Treat Knock Out Roses with Black Spot

Knock Out Roses are genetically modified rose plants made to withstand cold winters, sunlight and other elements with little human interference. Even these specially designed Knock Out Roses are not immune to plant diseases, including black spot. Black spot is a fungus that begins growing on the rose's leaves and turns into black patches all over the plant.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Pruning clippers
• Fungicide
• Funginex

1. Prune away all the leaves on which you see black spot. Discard the leaves in a compost pile or trash, away from the Knock Out Roses.

2. Spray a fungicide onto the Knock Out Rose bush. Three days later spray the bushes again. Wait three more days and spray the Knock Out Roses for a third and final time.

3. Use a funginex fungicide (such as Ortho's Funginex Rose Disease Control or Rose Pride) on the Knock Out Roses once you have complete the fungicide treatments. The funginex prevents the return of black spot.

4. Repeat the funginex spray once every seven to 10 days, and continue the treatment throughout the summer. Once the colder months hit, stop applying the funginex. Resume the treatment in the spring.

References

• Treat Roses