"American Rose" Article on Organic Japanese Beetle Control

Here is an article about organic control of Japanese Beetles, which I wrote for the July/August American Rose magazine, in collaboration with rose gardener extraordinaire and fellow organic gardener, Paul Zimmerman, who writes a regular column in the American Rose.  I think it's very promising that the American Rose Society (ARS), of which I am a long-time member, is taking up the cause of organic rose gardening.  ARS president, Pat Shanley, is also an organic gardener and I am encouraged that ARS is reflecting her leadership and commitment, something that has been a long time coming.

Someone asked me the other day what it means to be an "organic gardener", and that's a good question.  I would say that you must first recognize that most destructive or invasive insects can be controlled by beneficial insects or, as in the case with Japanese Beetles, by methods that kill off or divert the JBs from their target food, such as roses.  In other words, going organic means making a commitment to stop using insecticides, in order to stop killing-off the beneficial insects that then kill-off the destructive insects you are targeting.  A simple example is having an infestation of aphids and believing (correctly) that you can squirt them off the plants with a sharp stream of water a few times, while awaiting the arrival of lady beetles which will take them out permanently.  However, if you succumb to the knee-jerk reaction of spraying insecticidal soap or something stronger like carbaryl (Sevin), you will kill off both the lady beetles and the aphids, which will surely return and have no natural predators to hold them down.  With Sevin you will also have killed off the bees and other pollinators, which begins a downward spiral toward creating a toxic waste site, which, unfortunately, many pretty rose gardens already are.

The only exception I can think of is the use of a miticide to eliminate eriophyid mite infestations. Spider mites can usually be held down with regular water washings, but the hundreds of different eriophyid mites, including phyllocoptes fructiphilus, which carries the rose rosette virus, are far more difficult to control without a miticide like Abamectin (Avid).  Miticides are different than other insecticides, however, in that they do not kill off most beneficial insects (except naturally occurring beneficial mites which can be reintroduced after the miticide is finished). In this regard, please read my most important blog post "The Pesticide-Free Rose Garden":
http://theminnesotarosegardener.blogspot.com/2016/05/the-pesticide-free-rose-garden.html

And now, here is our new American Rose article on organic control of JBs... a good place to begin an organic gardening journey:

Organic Japanese Beetle Control

By Jack Falker “The Minnesota Rose Gardener” and Paul Zimmerman “Paul Zimmerman Roses”

JBs mating on Earth Song

Using insecticides to control Japanese Beetles (JBs) destroys beneficial insects (like lady beetles) and pollinators (like bees and wasps) and accomplishes virtually nothing in controlling JBs, other than killing off the current cloud of invading critters.

To control JBs organically, you must know your enemy.  First, understand that most of the JBs invading your garden come from amazing distances, up to five miles away, where they pupate in the rich turf of golf courses, cemeteries, parks, pretty neighborhood lawns etc.  In other words, the vast majority of JBs you see during the four or five weeks they invade your garden do not originate in your garden or lawn. So, you can spray them with insecticides but you can’t stop them from coming; and you can treat your lawn with a grub control like the milky spore bacteria to control the JB grubs for next year, but unless everyone within a five-mile radius does the same thing, you can’t stop them from coming and coming and coming.

The first step in organic JB control is pretty simple: once in the morning and once in the evening, knock them off the buds and leaves of your roses into a can of soapy water. Skin-tight surgical or milking gloves help, if you’re squeamish about touching the JBs.  You’ll soon realize that JBs have a dropping instinct, which makes them easy to drown.  They’re harder to catch in the hot sun of mid-day, when they quickly fly away. You’ll find that JBs are very docile and don’t sting or bite, leaving only a little stain in your hand of what we’ll call “beetle juice”. Using a few drops of dishwashing detergent in the water creates surface tension and impedes them from making an emergency takeoff.  Here’s how that looks:

Drowning JBs in Soapy Water

This is important: Don’t be tempted to squish JBs!  When you squish a female JB, her sex- pheromone is spewed out and brings in every male in the neighborhood!  This is also why JB traps are not a good idea, at least in your own garden.  Here’s a quote from the University of Minnesota on JB traps:

“Pheromone traps contain the sex pheromone of the JB female. The pheromone is very powerful and will call in beetles from a few thousand feet.  Research demonstrated that more beetles fly toward traps than are caught, resulting in surplus beetles that feed on your plants. Think twice before purchasing and installing a pheromone trap.” 

JBs are amazingly canny critters and it's useful to observe what they do as they approach your garden.  When a JB arrives in the garden, it hovers, like a helicopter, looking for a suitable place to land. Almost always, it will land on a flower or leaf that has one or more JBs already on it, or on a flower or leaf that has been previously chewed by other JBs; obviously attracted to the sexual pheromone of other JBs.  Therefore, it's important to get rid of tainted leaves and flowers, whenever possible. It’s hard to pluck a brand-new bud that has two JBs imbedded in it but it's necessary, in order to stop it from attracting incoming beetles.   Using the old-fashioned, thumb and forefinger method of dead-heading, while drowning JBs, is very effective in encouraging rapid growth on roses, which is indicative of the positive multiplier-effect that organic gardening always has.

Nowhere is this more evident than in the mid-south, where the infestation of JBs is huge. In 2016, an organic rose-gardener in Virginia was ready to succumb to commercial spraying of the pyrethroid Demand CS to remedy a seemingly uncontrollable infestation of JBs.  Here is the classic organic-gardening advice she received from rose-gardener extraordinaire, Paul Zimmerman, who gardens in South Carolina:

“As organic gardeners, we don't use insecticides. We build a host environment for beneficials and let them take care of it. That works for native pests but, of course, JBs are not native so they have no enemy.

“Around here the JBs appear in early June, which is after our spring flush. When the JBs are out in full force, we clean up the gardens from the spring flush and get them ready for fall. We trim the roses back, do a thorough deadheading and clean out dead and weak wood. Essentially, we’re cleaning out a lot of the parts of the roses the JBs like, during normal maintenance. As the beetles start to wind down, the roses wake back up again.

“We’ve also added perennials amongst the roses. This was for aesthetics but more so to help create a host environment for beneficials. The JBs seem to flock to the perennials and, while there is some damage, it's not as noticeable as on the roses. Essentially, we work with the JBs that way, using their arrival as part of normal summer cleanup, and plant other plants they find more attractive.”

An Ultra-Beneficial Lady Beetle on a Companion-planting Echinacea in my rose garden

As in South Carolina, we use companion plantings in and around our Minnesota organic rose gardens, for both insectary and aesthetic purposes. We have beds of zinnias where the JBs gather and we now drown more JBs on the zinnias than on the roses; lots of chewed leaves but they’re very fast-growing and keep ahead of the JBs. We also have big shrub-roses in our tomato/insectary garden, away from the main rose gardens, that attract clusters of JBs, which we drown, eight and ten at a time. The shrub they really like is Dr. David Zlesak's amazing "Above and Beyond" and, since it's done blooming for the year, we cut it back, making it far less attractive.

JBs love Zinnias more than Roses (so plant zinnias)

The key element in organic gardening is PATIENCE! Remember that JBs only last about four weeks and, if you work hard to deter them organically, they ultimately go away, leaving you with lots of beneficials and pollinators, as well as fully fertilized and dead-headed rose gardens for the rest of the growing season.  Remember that every JB you drown is a monster-bug that can't breed more monster-bugs next year.  It’s particularly enjoyable taking them down when they’re atop one another, stopping the breeding cycle.

For more information, see these “Minnesota Rose Gardener” blog posts:

http://theminnesotarosegardener.blogspot.com/2017/07/controlling-japanese-beetles-organically.html

http://theminnesotarosegardener.blogspot.com/2015/07/the-beetles-are-coming-beetles-are.html

Controlling Japanese Beetles Organically

Author's note: One month after posting this, the JBs are the worst I've ever seen; very unlike how they started out.  That obviates what I said in the first paragraph below but doesn't change my conclusion that drowning them and distracting them with other plantings is the only viable solution. But I really hope they'll be gone soon.  I'm currently drowning several hundred daily, including those pictured on David Zlesak's "Gaye Hammond" below:

JBs on "Gaye Hammond" 8/8/17; they drowned immediately after posing.

I saw my first JB on June 19th this year, the same date as 2016 but, unlike last year, I saw very few in the next two weeks, until after the 4th of July, when they started to show up in earnest.  They're still not at the levels of previous years, however, which makes me wonder what might be happening here in east-central Minnesota this year.  My best guess is that the four golf courses (and one cemetery) within a five-mile radius of my garden have started using grub control on their fairways and lawns.  Unfortunately, that probably means they are using neonicotinoids, like imidicloprid, which have been strongly implicated in bee colony collapse disorder.

In the last few days, I also noted that a Master Consulting Rosarian in the Minnesota Rose Society said on Facebook that he is spraying JBs with carbaryl (Sevin), apparently unconcerned (or unaware ) that Sevin kills bees, lady beetles, predatory wasps, syrphid flies, lace wings and virtually every other beneficial insect in the garden. I also noted that the Minnesota Rose Society posted the same advice on their website.

In my mind, spraying JBs with an insecticide like Sevin is the classic "fool's errand" because what you spray today affects the JBs (and pollinators) in your garden for a day or so and has no effect on the thousands of JBs arriving in your garden from somewhere within a five-mile radius of your garden for the next six or eight weeks.  This is also true of the pyrethroids, which linger longer in the garden. The implication is that, ultimately, one would have to spray again and again, creating, for all intents and purposes, a toxic waste site, devoid of all life except roses. (Confession: I know this so well because I sprayed insecticides, especially the pyrethroids, to control JBs, until I became aware of the damage I was doing.  It has taken several years for the beneficial insects to return and, happily, they are back in force.)

The irony in all of this is that organic control of JBs is extremely easy and totally non-disruptive to the eco-system of your garden.



Know Your Enemy

To control JBs organically, you must know your enemy.  First, understand that most of the JBs invading your garden come from amazing distances, up to five miles away, where they pupate in the rich turf of golf courses, cemeteries, parks, pretty neighborhood lawns etc.  In other words, the vast majority of JBs you see during the four or five weeks they invade your garden do not originate in your garden or lawn. So, you can spray them with insecticides but you can’t stop them from coming; and you can treat your lawn with a neonicotonoid grub control, like imidicloprid, or a biological control like the milky spore bacteria to control the JB grubs for next year, but unless everyone within a five-mile radius does the same thing, you can’t stop them from coming and coming and coming.

Here's an article I wrote one year ago: "Attacking Japanese Beetles -- Know Your Enemy":

http://theminnesotarosegardener.blogspot.com/2016/07/attacking-japanese-beetles-know-your.html

Organic JB Control

The first annual step in organic JB control is pretty simple: once in the morning and once in the evening, knock them or pick them off the buds and leaves of your roses into a can or bucket of soapy water. Skin-tight surgical or milking gloves help, if you’re squeamish about touching the JBs.  You’ll soon realize that JBs have a dropping instinct, which makes them easy to drown.  They’re harder to catch in the hot sun of mid-day, when they quickly fly away. You’ll find that JBs are very docile and don’t sting or bite, leaving only a little stain in your hand of what we’ll call “beetle juice”, so I seldom wear gloves when working on them. Using a few drops of dish-washing detergent in the water creates surface tension and impedes them from making an emergency takeoff. Here's what that looks like:

The second step (actually it should be the first overall step) is to redesign and prepare your garden for organic JB control.  I call it varying and mitigating the JB target so they don't land solely on the roses. Having a variety of perennials, annuals  and herbs, like oregano and cilantro, among your roses gives the JBs somewhere else to land and the damage is not nearly as noticeable as it is on the roses.  I have beds of zinnias where the JBs gather and I now drown as many JBs on the zinnias as on the roses; lots of chewed leaves but they’re very fast-growing and keep ahead of the JBs.  Here's a recent picture (just before that mess of JBs got knocked into the soapy water.):

JBs Love Zinnias (so plant zinnias with your roses)

I also plant patches of oregano in each rose bed to attract beneficial insects, particularly predatory wasps, into the garden.  The JBs like that too, which makes it doubly effective, and they certainly can't hurt the oregano!  Here's how that looks right now (and that JB bit the dust too, after posing for me):

I also have big shrub-roses in my tomato/insectary garden, away from the main rose gardens, that attract clusters of JBs, which I drown, eight and ten at a time. The shrub they really like is Dr. David Zlesak's amazing "Above and Beyond" and, since it's done blooming for the year, I cut it back with my electric hedge clipper, making it far less attractive.

Step three is to aggressively dead-head your roses while attacking the JBs.  One of the things I have noticed is how JBs tend to cluster on spent blooms that are losing their petals.  I don't know why that may be but it's a very good reason to get all of those spent blooms off the plants. And, while you're doing that, you're setting up your roses for the next flush of bloom, when the JBs are finished.  Here's what I mean by spent bloom clustering.  If  you look carefully, you can see the sexual activity resulting from the JB female pheromone:

JBs Mating on Earth Song

If you don't panic, there's a bit of sport in this too. JBs are amazingly canny critters and it's useful to observe what they do, especially in the heat of mid-day, as they approach your garden.  When a JB arrives in the garden, it hovers, like a helicopter, looking for a suitable place to land. And, almost always, it will land on a flower or leaf that has one or more JBs already on it, or on a flower or leaf that has been previously chewed by other JBs; obviously attracted to the sexual pheromone of other JBs. (I've actually gotten pretty good at grabbing them in mid-air as they look for a sexy place to land, and that's fun.)  So, it's important to get rid of tainted leaves and flowers, whenever possible. It’s really hard to dead-head a brand-new bud that has a JB embedded in it but it's necessary, in order to stop it from attracting incoming beetles. Using the old-fashioned, thumb and forefinger method of dead-heading, while drowning JBs, is very effective in encouraging rapid growth on roses, which is indicative of the positive multiplier-effect that organic gardening always has.  There will be more new buds!

This is important: Don’t be tempted to squish JBs!  When you squish a female JB, her sex- pheromone is spewed out and brings in every male in the neighborhood!  This is also why JB traps are not a good idea, at least in your own garden.  Here’s a quote from the University of Minnesota on JB traps:

“Pheromone traps contain the sex pheromone of the JB female. The pheromone is very powerful and will call in beetles from a few thousand feet.  Research demonstrated that more beetles fly toward traps than are caught, resulting in surplus beetles that feed on your plants. Think twice before purchasing and installing a pheromone trap.” 

For more information on this, please take a look at my article from last year: "Attacking Japanese Beetles -- Organically":

http://theminnesotarosegardener.blogspot.com/2016/07/attacking-japanese-beetles-organically.html

Also, please take a look at my most important blog post of all "The Pesticide-Free Rose Garden":

http://theminnesotarosegardener.blogspot.com/2016/05/the-pesticide-free-rose-garden.html

  

And finally, please remember that the key element in organic gardening is PATIENCE!

Don't panic; JBs only last about four weeks and, if you work hard to deter them organically, they ultimately go away, leaving you with lots of beneficials and pollinators, as well as fully dead-headed rose gardens, ready for the rest of the growing season.  And remember that every JB you drown is a monster-bug that can't breed more monster-bugs next year.  It’s particularly enjoyable taking them down when they’re atop one another, stopping the breeding cycle.

Jack Falker

@mnrosegardener

Edina, Minnesota

612 385-6226