geraniums – asian beetle


I think the blooms on my geraniums are being attacked by asian beetles. I have seen them on the plant lately. Is it coincidental that the flower petals look mushy? what can i do? move the plant entirely? not sure if these beetles like a certain area of my garden.


Thank you for contacting the Toronto Master Gardeners.

It sounds like the insect that you have seen on your geraniums (Pelargonium spp.) could be Japanese Beetle. Japanese Beetles love hot dry weather which we have certainly had recently, and the adults typically emerge in late June through mid-July from the soil under lawns where they lay their eggs. However adult Japanese Beetles skeletonize leaves but you mention that your geranium flowers are mushy. Here is a link to the website for the Ontario Ministry of Agriculture, Food and Rural Affairs that might help you to identify whether or not it is actually Japanese Beetle that you have seen on your geraniums. This website lists many plants that are susceptible to Japanese Beetle. They are very active heavy feeders, so I think it is unlikely that they will confine themselves to just one part of your garden.

We get lots of questions about Japanese Beetles, so there is lots of information on our website about these annoying pests and how to control them. Simply type in ‘Japanese Beetle’ in the box under Find it Here on our Home page.

Here is some information from a previous post on our website :

It appears that you have an infestation of Japanese beetles. Japanese beetles love hot dry weather, so this summer has provided optimal conditions.

Japanese beetles lay their eggs in the soil under lawns.  The larvae will overwinter in the soil and continue feeding as the weather warms in the spring. Once the larvae are full grown, they will pupate and emerge as adults in late June and early July.  The adult beetle will continue to feed on foliage through July and August.

Your control strategy should be multi-pronged.  Adult beetles emit a pheromone that helps them find each other.  Getting rid of the adults can slow your infestation. Experts say that the best method for control is to hand pick them in the early morning or late evening when they are less likely to be flying, and simply knock them into a pail of soapy water, where they will drown.

You can also try to prevent an infestation next year by treating your lawn for larvae.  You can apply beneficial nematodes to your lawn in late summer.  Nematodes are a type of roundworm that feeds on grubs. Be sure to select a type of nematode specific to the larvae of Japanese beetles, and to apply as per manufacturer’s instructions.

There are also pheromone traps that will attract adult beetles.  However, there is always a risk that these traps will attract more beetles from surrounding areas to your yard.  They are most effective in large yards where you can direct the beetles far away from your plants.


Good luck with your geraniums !