Is there anything I can put on my garden to deter or kill grasshoppers,
without hurting my ladybugs?

A microbial insecticide called Nosema locustae is sold under various trade
names for grasshopper control. This is a protozoan disease that occurs
naturally among grasshoppers and has been commercialized by mass production
under laboratory conditions. It does not affect other, beneficial, insects in
your garden.
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