Extreme measures
Chicken Moat and tunnels for grubs
Chicken moat is a fenced area around your fenced in garden. The chickens patrol the perimeter.
Chicken tunnels; Some people set up tunnels in the garden walking rows using stiff wire and some sort of cloth cover. Row covers, shade cloth etc.
Sounds great!!:) The only problem is chickens eat the good bugs (ladybugs, etc.) too.