Give up and just build a bird-proof cage. I've
fought this problem in nearly every known way, from
supplying wholesome food to using fake owls, and
the only thing that is reliable is a chicken
wire cage over you plants. I know that Rick
Walker has used a PVC frame with shade cloth
over it to keep out birds and squirrels with
a great deal of success, but I prefer the wire
since the squirrels can't eat through it.
Regards,
Robert