What causes the round bore holes in the canes of hybrid tea roses? What can I use to treat it? The cane looks black this spring and no new signs of growth as of yet. |
It sounds like holes made from the rose cane borer, an insect that tunnels into the cane soon after roses are pruned. Seal all newly cut canes with wood glue or one of the commercial preparations available. For existing holes, cut the cane back an inch or two at a time until the hole is no longer visible. Then seal the cane with wood glue. |