The adult Japanese Beetles feed on our prized plants for about 6 to 8 weeks beginning in early July. They have already skeletonized the leaves of my 3-year-old ‘Firebird’ crabapple!
‘Firebird’ crabapple with JB damage
As I am “vertically challenged” I didn’t notice the damage as soon as I could have. They were all over the top of the tree. Younger trees are more vulnerable to the damage. For that reason, I’m being especially attentive to watering this tree right now during our hot/dry weather. Keeping this tree as healthy as possible right now will help it recover.
Where I DID see them was on my native Leadplant that is 6 ft away from the above crabapple. It’s a reminder to me to look up!
How many do YOU count? Hint: 5 – look closely
I’m a big proponent of capturing them and drowning them in water with a little soap. What I didn’t realize is that I shouldn’t just toss the carcasses out in the street or in the lawn! Jenny, the Gertens Expert, explained they must be placed in a plastic bag and thrown in the garbage! Watch her full video
There are several products that are great for killing the adults that do NOT harm you or your pets. Captain Jack’s Deadbug Brew is just one of them. Jenny is a proponent of the active ingredient used, Spinosad.
The adults live for about 60 days. During that time, the females can lay up to 60 eggs in your lawn. That’s where Grub Control comes into play! You can apply grub control from mid-July until early September. The earlier the better as that’s when the grubs are at their most vulnerable and closest to the surface of your turf.
As you can see, the grubs grow and work their way deep into the soil over winter to emerge again in July. As you can also see, grub control can also be effective when used in Spring from April through May.
The Garden Scoop applied Bonide Grub Beater in August 2021. I recommend this granular product and urge you to follow directions using a spreader to apply! The active ingredient is Imidacloprid. It offers minimal risk to mammals and fish.
NOTE: While I still had some JB issues this year, they really aren’t NEARLY as bad as years past. In fact, I only found 2 of the adults on my roses! A shrub they find particularly attractive in 2021, as you can see in the photo below.
The ‘Scoop’s Music Box rose in 2021
Japanese Beetle adults also love vining plants including grape vines and Virginia Creeper. I ripped out a beautiful one I had growing on my fence because the leaves were covered in mating JBs, UGH. Their pheromones just draw more beetles in. Another reason NOT to use those traps/baggers if you live in a neighborhood.
So, garden warriors, you still have time to start the process of battling this beast and ridding your landscape of these invasive insects. We have one other insect that offers us hope in our battle against Japanese Beetles. That is the Winsome Fly. I talked about this guy last year!
While there are other chemical options, I urge my readers to use more pet and human friendly methods.
Take THAT, JB
