By Rick Sall
Many people are noticing that roses, the white ones in particular, are being damaged by beetles feeding on the blossoms. I have actually not seen this form of beetle in the desert in these numbers prior to this year. The Hoplia Beetle emerges from the soil in the Spring and feeds on flowers for several weeks before returning to the ground to lay eggs, thus completing a life cycle. They are particularly attracted to white flowers and will basically ignore the cherry-red blossoms of the Knockout Roses growing nearby- this is a classy bug with good taste! Before you panic and start throwing the P word around (pesticides), you might want to consider some “IPM” techniques. IPM, or Integrated Pest Management, uses various cultural and biological pest control techniques before resorting to chemical control. The Hoplia Beetle, as shown in the first photo, only feeds for a few weeks, and many roses can still bloom quite nicely. I have a climbing Iceberg Rose that the Hoplia Beetles are no match for; the blossoms may actually outnumber the beetles. The two photos show the same plant with no chemical control required. Click here for the University of California IPM guidelines for Hoplia Beetle – these guidelines contain all you need to know, as well as some ideas on cultural control. A white bucket filled with water and some dish detergent is my chosen method – and my Climbing Iceberg Roses are showing their appreciation of the effort.