All the leaves are gone on all my knockout roses! What should I spray?

S. H
by S. H
The leaves on my knockout rose are lacey or completely gone! Help!
  10 answers
  • Luis Luis on Jun 09, 2014
    Sounds like it could be black spot. It is a really common fungus that turns the leaves yellow with round black spots on them. they fall off really quickly. Black spot will not kill your rose, but it will defoliate it and if severe enough, damage any blooms. try a product by Bayer - 2 in 1 systematic rose care. Also, when wattering the plant, try not to splash any water on the leaves, as this can accelerate formation of black spot.

  • Donna Shipley Donna Shipley on Jun 09, 2014
    When the leaves are gone, spray the stems.

  • Vicki K Vicki K on Jun 09, 2014
    It was found that Knockouts got a virus or fungus just like other roses do, so their popularity tanked this year. Spray w/ fungal spray and hope it comes back.

  • Doris Hare Doris Hare on Jun 09, 2014
    NEEM Oil

  • Doris Hare Doris Hare on Jun 09, 2014
    NEEM not only treats black spot but insects also.

  • Doris Hare Doris Hare on Jun 09, 2014
    It is both a fungicide and insectide.

  • Out of curiosity-how long has it been planted? and did you buy it distressed (on the markdown rack)?

  • Douglas Hunt Douglas Hunt on Jun 10, 2014
    It sounds like rose sawfly damage. Neem may work, or an insectide containing pyrethrin.

  • Leslie Long Leslie Long on Jun 10, 2014
    I agree with Doris Hare! NEEM is a 3-in-1 organic. It is a fungicide, miticide and insecticide so will work on any of the three culprits, since she isn't sure what it is. It would be my first choice and it will not hurt any beneficial insects. Good luck :)

  • Vicki K Vicki K on Jun 10, 2014
    I need to get some NEEM oil! I have mealy bugs and ants on my crepe myrtle. I was going to use alcohol and water in a spray.