Holes, rips, or tears in rosebush leaves can be caused in different ways. In some cases, the wind whips the foliage so hard that the leaves will get puncture wounds in them from their own thorns. Small pea-sized hail will also cause holes, rips, or tears in the foliage.
If you notice that the holes in your Knockout Rose leaves are perfect ovals or circles, you probably have active Leafcutter Bees. Though the damage is relatively minor, the cuts in the leaves are unsightly and can be avoided. These bees are solitary and do not live in colonies, so infestations are not likely.
When we were researching we ran into the question “What causes holes in flower leaves?”.
Holes in flower leaves usually indicate insect pests rather than disease, which tends to cause spots on the leaves or dropping leaves. Holes are caused by insects with chewing mouthparts, such as caterpillars and beetles. Before you rush for a can of insecticide, though,.
Why are the leaves on my knock out Rose dying?
It might be a combination of high winds and a neighboring thorny plant, or perhaps cats are chewing on the lower leaves — they often like to rub and taste leaves as they pass. Search first for the other three problems because insect, disease and chemical damage are potentially life threatening for knock out roses.
Leaf cutter bees also plague knock out rose leaves when they’re cutting away holes in the leaves to use in building their nests. They rarely take much from the plants, however, and their season is short.
What are the white spots on my Rose leaves?
These are similar in appearance to the common rose slug; sawfly larvae are distinguished by the white spots encircling their body, while bristly rose slug larvae are covered in hair-like bristles. Round holes about 3/8-inch appearing either singly or in groups on your rose leaves are usually caused by female leafcutter bees (Megachile spp.).