I recently moved to a Plant Hardiness Zone 6 and unlike my previous Zone 5, Japanese Beetles are
everywhere. My neighbour regularly plucks them off her rosebushes and, wanting to avoid
pesticides, asked me what else she can do. This little green and coppery-red beetle is all over
warmer parts of Canada and the US. CFIA has protocols in place in Vancouver for handling
Japanese Beetle infestations without spreading them. In light of this, I thought I would share some
findings on how to control, or at least limit the spread of, the Japanese Beetle.
Japanese Beetles feast on the flowers and leaves of over 300 plants and trees. Not only that, a
female will lay approximately 50 eggs at a time, making it easy for numbers to get out of control.
Like all beetles they go through the egg, larvae (grub), pupae, adult life cycle. Fortunately, they are
susceptible to cultural, biological, and chemical defenses at different stages.
In the grub stage:
Milky Spore attacks the white grubs of the Japanese Beetle before it can develop into an adult, this
takes a couple of years to work, but will last for 10 years.
Nematodes are beneficial against the Japanese Beetle with the most effective species being
Heterorhabditis bacteriophora (commercially available as Heteromask, NemaSeek or Terranem).
Starlings are the biggest aerial predator of Japanese beetle and will enjoy them as grubs or adults
Chemical: Mix 2 tbsp dishwashing soap diluted in 1 ga of water and spread of 1000 sq ft. This will
force the grubs to the surface of the soil where predators will pick them up (choose soaps
made from animal or vegetable oils in accordance with the SOUL Standard).
In the adult stage:
Cultural: Knock the beetles into a bucket of soapy water, the soap will prevent them from flying
away and they will eventually drown.
Chemical: Neem oil (the SOUL Standard allows neem oil when registered for use in Canada)
Remember, pesky insects like the Japanese Beetle can be a sign that something isn’t right the
garden. Be sure to address overall soil and plant health and keep soil microbes happy.
Japanese Beetles also love turf grass, opting for real grass over turf may go a long way.
For more information on Japanese Beetle and how to combat it, check out the sources below.
Master Gardeners of Hamilton County, TN
Planet Natural Research Centre
Gardeners Supply Company
Compost tea is a hot topic during the gardening season. Pumping air through a mixture of compost and water will draw the aerobic microbes on the compost into the mixture for ease of spreading on your garden and lawn. With the right ingredients, and a good brewer, compost tea is easy to make to promote soil and plant health.
Making it: Using non-chlorinated water, good quality compost and microbe food, pump air through the mixture for 24-48 hours. Once the brewing is complete, it should be used within six hours to ensure the undesirable anaerobic microbes don’t take over. The tea can be used as is, or diluted to cover as much area as possible.
The science: Pushing the air mixes the microbes from the compost into the water, where they flourish on oxygen and microbe food. Steeped tea (no air bubbles) may not sufficiently activate aerobic microbes, and anaerobic microbes could proliferate, creating an ineffective compost tea.
Benefits of using compost tea:
· Spray it directly on plant leaves to protect them from disease;
· A little goes a long way, tea can cover a larger area than the same amount of compost on it’s own;
· Your soil will love the extra microbes
For more information about compost tea or to purchase a brewer visit
The Organic Gardener’s Pantry (www.gardenerspantry.ca) or Smiling Gardener (www.smilinggardener.com)
SOUL is seeking a part-time Executive Director. Reporting to the board of directors, the successful candidate will be an innovative, driven individual with strong leadership skills and experience with not-for-profit governance that will help take SOUL to the next level. Other qualifications should include securing funding, project management, and knowledge of the Organic Land Care Standards.
This is a work from home position with a flexible schedule, some evening and weekend work may be required.
Roles and responsibilities include:
Please submit your cover letter and resume by September 30 to firstname.lastname@example.org.
Society for Organic Urban Land Care (SOUL)