Rose Slug

What is leaving holes in my roses? Rose Slug

Do you see window pane-type holes or complete holes in your rose leaves and no bugs? The problem is rose slugs. Rose slugs are tiny and the same color as the leaf. They feed on the underside of rose leaves.

What are rose slugs?rose slug leaving holes in rose leaf

Rose slugs are not slugs. They are part of the sawfly family with an early appearance of a minuscule caterpillar. The young larvae create large holes in rose leaves’ underside to total leaf skeletonization as they mature. While their damage may hurt the rose’s appearance, it rarely affects the plant’s overall health.

How do you treat rose slug?

There may be several generations of rose slugs, so be consistent with treatment.

Here are 3 ways to treat the problem:

  1. HAND SMASHING
    Early in the morning, hand smashing the rose slugs as you can find them on the leaves’ undersides is very effective!
  2. REPEATED FOLIAR SPRAYS
    Use Insecticidal Soaps or Horticultural Oils, but make sure to spray the leaves’ undersides where the rose slugs are feeding, not the tops of the leaves.
  3. SYSTEMIC INSECTICIDE
    Apply a systemic insecticide such as a 3 in 1 Rose Care, Optrol, or Bonide, Bayer, or Fertilome Tree and Shrub Insect Control. The insecticide kills the larvae as they feed on the leaves. It is most effective to apply before damage is visible. However, you can use it after.

Note: Hand smashing and foliar sprays are the most effective immediate controls. But a combination of the systemic and foliar sprays will do an excellent job controlling them.

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