I garden organically. Grasshoppers love me, especially my brassicas. How can I teach these critters to share? I got no kale last year, after replanting three times. It was all holey. This is the second year with this problem, which seems to be getting worse. Can you help please?
Macomb County Michigan
There is little available research for grasshoppers in the home garden in Michigan and it is because they are seldom a problem for the home gardener. In fact, yours is the first grasshopper question in memory for me. They are sometimes a problem here in Michigan for fruit farmers however. Voracious feeders, they will eat just about anything. I'm sending links from other parts of the country where they are a more serious problem.
You will read that they can be controlled chemically with carbaryl, if the infestation is not too large. We at the Extension Offices highly recommend against that option however. This is because most pesticides will produce collateral damage taking down other insects, many of them beneficial to the home gardener. And carbaryl is highly toxic to bees. Further, pesticides often fail to control your target pest effectively as well.
Seems that the best solution would be to erect a physical barrier. Aluminum screen material would block grasshopper entry while allowing in water and sunlight. A more permanent solution could be building wood framed raised beds, providing a base for a good frame to be built for the screening. You can defeat the grasshoppers, depending on how much effort you want to put into it.
Good luck! and read on.........
I'm glad to see that you recommend against chemical warfare here. As an organic gardener, I believe we've gotten ourselves into an environmental mess by spraying indiscriminately & killing our insect helpers, bees included.As for a physical barrier, how do my bees get in to pollinate?I have read about using diluted vinegar. My soil Ph is a bit high, but what would this do over time? Also had Bt suggested. What good bugs does that kill? Thanks for your input.
If grasshoppers are your problem, they usually do not mature or become severe until mid summer or later. Your plants will flower earlier in the year, meaning you could leave any cage open until later in the year.
However, I question if grasshoppers are your problem or do you have the much more common cabbage worms eating your brassicas? Holes in your plants seem to indicate cabbage worms. Bt is what organic gardeners use for caterpillars and it safe to humans and other insects. Inspect your plants, often on the undersides of the leaves, for small green caterpillars, as soon as you see the first hole.
If this is what you have, the best way to control the green cabbage worm, cabbage worm or cabbage looper is with Bacillus Thuringiensis or Bt. It is a naturally occurring bacterium found in the soil so It won't harm humans or beneficial insects. Only worms/caterpillars. No it won't kill earthworms. This works and is as easy as spraying your vegetables. Bt is one of the few pest control products that will work effectively without collateral damage.
Perfect answer! Since it was tiny transplants that originally got taken down to their stems & grasshoppers don't come to dinner early, I will look to the worms instead. Thank you so much.
Swell, thank you. Again, good luck!