Don’t worry I’m not cussing any real person, JB as in Japanese Beetle. This year we have been raging a war (literally) on these annoying beetles that have been feasting on our knockout roses. You know, knockout roses are generally disease resistant and are very easy to maintain. That was the case last year but this spring after a round of very showy flowers the beetle menace started.
If you haven’t been graced by the presence of these unwanted guests, this is what I’m talking about.
There are swarms of them on every bud and most of the leaves. The adults feed on the buds first then attack the leaf eating up most of it leaving it looking like a skeleton.
We sprayed the pesticide Ortho Rose & Flower Insect Killer (the right one in the below pic) for the first time 6 weeks ago and the problem seemed to go. The new growth (pic on the left above) was trouble free.
Just as the buds on the new growth were starting to bloom, two days ago, they stuck again! This time B bought the Bayer Natria but we didn’t realize that it does not work on Japanese Beetles. Naturally it didn’t work even after a thorough spraying (the first two pics).
Some research online revealed that we should be on the watch out not just this season with repeated sprays (their average life span is 30-45 days) but also the next few years. It seems the females burrow 2-3 inches into the soil and lay eggs, which spend the next 10 months in the soil as white grubs while they grow feeding on grass roots. In spring they move up the root zone followed by a feeding period of 4-6 weeks after which they pupate and emerge as adults.
Armed with this info we decided to step up our game and went with another spraying of Ortho Rose & Flower Insect Killer followed by an application of Bayer 12 month Tree and Shrub Protect & Feed.
This seems to be a very strong fertilizer and comes with strict warnings not to use it on any plants that will bear edible fruit/veggies. It is a fertilizer cum insecticide that is supposed to work for 12 months. Comes as a green liquid which you dilute and pour near the root.
Keeping our fingers crossed. Hopefully we can get rid of this menace before they do severe damage to our lawn (the grubs thrive in a well watered good lawn eating away the roots).
Do you have a JB problem too (I think it is mainly an East Coast issue)? What do you do to keep them at bay?
Update: The Ortho Rose & Flower Insect Killer in combination with the Bayer 12 month Tree and Shrub Protect & Feed seems to have done the trick! Yay!