It ’s that time of year where every trip-up to the garden involves an inspection for Nipponese beetles . Are they here yet ?
So far , in my garden in St. Paul , the solvent is no , not yet . Nipponese beetles typically seem in Minnesota in late June or former July . They live for 6 to 8 weeks , creating havoc the entire time , eating roses , green beans , birch rod trees and about 300 other plants . They pair ; the grub hide in the soil for the winter , and it ’s all over before the Minnesota State Fair .
While beetles have been in the United States more than 100 years , they have only been in Minnesota about 50 . In 2018 , we first spotted them on June 26 . In 2017 , the first sighting ( for me ) of Japanese beetle was not until July 3 . In 2015 , they werehere by June 24.I’ve determine none so far .
Roses are a favorite target of Japanese beetles.
We ’ve had a nerveless , wet springiness , so perhaps they are delay . Many gardeners are hoping that the cruel winter we had with early sub - zero temperatures and a lengthy cold-blooded flow may have knocked them back , but conversations with University of Minnesota entomologists indicate that is unbelievable . We did have a toughened winter , but beetle grubs stay below ground — sometimes as humble as 6 to 8 in below undercoat .
In improver , going into the winter of 2018/2019 , Japanese beetle chuck numbers were high . The U has a enquiry area in Rosemount where researchers counted 26 Japanese beetle grubs per foot . That ’s a batch . Grub numbers are most affected by drouth during the mating season .
handle with Japanese mallet
Once they get here , beetles area existent challenge . Keep an centre out for the Nipponese beetle because early interventions tend to be more successful .
Traps do entrance a luck of beetles , but they also bring more into your curtilage . They are not recommended unless you have a very large G and can set the trap away from your garden . The best non - insecticidal control is to knock the beetle into a pail of soapy weewee . Going out in the morning is in effect as they tend to be out and they move more slowly then . you could also add cover to plant you desire to protect . Fruit plants , however , should not be covered until blooming is finish and no pollenation is required . Insecticides can work , but the effective ones lean to harm bees as well . This articlefrom the University of Minnesota Extension covers your options and the pros and cons of each .
A long terminal figure option may be tonot plant the plant JBs lovethe most , such as roses and grape . It also helps to remember that this , too , shall expire , and most plants are not killed by Nipponese beetles .
