Question
How do I get rid of grasshoppers that are eating my marigolds?

Answer
Carolyn, grasshoppers are one of the more difficult pests to control. There are chemicals such as maliathon and Sevin which are fairly effective. Organic controls include pyrethrum and rotenone. A long-term organic control is Semaspore Bait, which contains nosema locustae, a disease specific only to grasshoppers. This product can only be purchased through organic gardening companies such as Planet Natural or Gardens Alive.

http://www.planetnatural.com/site/semaspore-grasshopper-bait.html

Most of the grasshoppers that eat the bait will die within 3 weeks. The surviving grasshoppers will fatally affect subsequent generations.  

One homemade remedy that I've heard is effective is mixing one part molasses with 10 parts water in a shallow pan. Supposedly, the grasshoppers are drawn to the molasses, enter the pan, and drown. Those who have tried it swear by it.  

I hope this helps. Good luck, and please write again if I can be of further assistance.  

Regards,  

Mike