Watch out beetles — BTG is back in town!
Back in 2015, I told you about a great new weapon in the organic arsenal: a new form of Bt known as “BTG.”
Like the other Bts**, “BTG” only affects one type of insect. In this case, it’s the rose-ravaging Japanese beetle and its many “cousins” in the scarab beetle family (Asiatic garden beetle, rose chafer, etc.).
Released exclusively by the mail-order firm Gardens Alive under the name “Beetle Jus”, this new Bt almost instantly stops Japanese beetles from feeding and they die soon afterward. And, like the other Bts, BTG affects no other form of life; it’s perfectly safe for people, pets, toads, frogs, butterflies, wombats — whatever you got.
The first run of “Beetle Jus” sold out quickly in 2015, and then the manufacturer had seemingly endless problems producing more. I have just received word that those problems have been solved and “Beetle Jus” is back and in stock — just in time for this year’s Beetle Mania!
**The original strain, “BTK,” kills pest caterpillars that chew on the sprayed leaves of plants; it has been around since the 1920s. “BTI” is a different strain discovered in the late ’70s; applied to standing water, it prevents mosquito eggs from developing into biting adults.
Step one: Monitor, trap …
In previous years, Japanese beetles have first shown up in the D.C. region early in July. That makes this the perfect time to prepare for this year’s invaders, because if you deter the first wave, you may be beetle-free the rest of the season.
Step one: Get a standard Japanese beetle trap and set it up next to your roses or other plants they typically attack. Check it every day, and the first day you see a beetle in the bag, take the trap down and store it inside your home or garage in a Ziploc bag for use next season. Do NOT leave the bag out there to collect more beetles. The lures attract four times as many rose munchers as would normally fly into your landscape, but the traps can only catch half.
Do the math: If you leave the trap up, you spend good money to double your Japanese beetle problems.
Step two: Spray away
Put one Japanese beetle trap near your smelliest roses, check it every day and take it down when you find your very first beetle inside. This technique is called “monitoring” and it’s what the pros use traps for — to identify when the pest first shows up, not to try and control the problem with multiple traps.
Step Two: Spray the plants that beetles love to eat with “Beetle Jus” — that’s what Gardens Alive calls their new Bt — a strain known as “BTG” (the “G” stand for “Galleriae”) that only affects beetles (and weevils) that feed on the leaves of sprayed plants.
If you have previously been beset by beetles, order your BTG now so that it’s on hand when the nasty little rose ravagers first show up.
Stop the first wave and you may be done for the summer
The D.C. area will soon be beset by Japanese beetles, and now is the time to prepare.
So, to repeat:
- Get a Japanese beetle trap so that you know when the first rose-ravagers emerge from the earth.
- Order the newest form of Bt, “Beetle Jus,” from Gardens Alive and have it on hand to spray your plants when those first beetles attack. (To the best of my knowledge, BTG is only available from Gardens Alive.)
Alternative to BTG: Cut all your fully flowered roses and bring them inside to display. Then, cover the rest of the plants with floating row covers or sheer curtains.
Either way, the all-important first run of beetles won’t be able to feed on your plants. And that’s all you might need to do.
When Japanese beetles first begin feeding, they emit specialized pheromones that attract and excite other emerging beetles. Prevent that first feeding frenzy at your place and the beetles will be forced to flee to other food, like your neighbor’s roses.
Once this year’s crop of beetles establishes their “turf” (sorry), they’ll mostly stay where they first got fed, and you may be able to stop protecting your precious plants.
There’s also a BTG for beetle grubs
Right now, Japanese beetles are in the final instars of their white grub stage and have moved up high in the soil. Soon, they will emerge from your lawn and landscape as armored adult beetles, intent on ravaging your roses.
But, you can stop them before they emerge with beneficial nematodes (microscopic creatures that attack and destroy lawn grubs, widely available via mail order and at hipper garden centers), or with BTG, which works against both Japanese beetle grubs and adults.
A granular version that Gardens Alive calls “GrubHALT” is designed specifically for use against lawn grubs. Water it into the lawn and it should stop those nasty white grubs from turning into armored adults.
(Note: In this case, don’t wait until you see the first beetles. Apply nematodes or BTG to your lawn as soon as possible this spring.)
Mike McGrath was Editor-in-Chief of ORGANIC GARDENING magazine from 1990 through 1997. He has been the host of the nationally syndicated public radio show “You Bet Your Garden” since 1998 and Garden Editor for WTOP since 1999. Send him your garden or pest control questions at MikeMcG@PTD.net.
