He's over in Pauuilo, they get loads of rain - about 8 and a half feet per year, but it's got loads of drainage so that should be good. His plants would need the same sort of water conditions as the worms, so if there's living plants shouldn't there be living worms? I'm suspecting he may put some sort of chemicals on his garden that the worms don't like. If someone uses chemical fertilizer does it chase worms away? The 'bunny berries' under the hutch are dry with no worms, but right behind the hutches where the berries from the upper level land along with rain, every shovel full is teeming with worms.
In any case, does anyone else add chemicals to their garden after using bunny berries for fertilizer? We only add in oyster shell to lower the acidity (oyster shell doesn't wash away) and some 'bio-char' (crushed charcoal that doesn't have lighter fluid on it) to give the nutrients somewhere to go instead of being washed away. Between bunny berries, oyster shell and bio-char, the gardens seem to thrive. The oyster shell and bio-char are only added every few years, but a layer of bunny berries is added between each planting.