leaf hoppers

I have leaf hoppers all over my garden. (small flying insects, green in color)
I have shopped around to look for a solution. For a year, I found nothing.
The plants die when too many of them stay on the leaves.
I would be very glad if I can buy some kind of leaf hopper killer for use in the future.
If anyone have any ideas, please share with me. Thanks.

jessie

 

http://www.discoverneem.com/neem-oil-insecticide.html

 

Thank you very much. I will get neem oil, for sure, and try it out.
I have hope that it will solve my hopper problem.
Thanks.