You'd be surprised by what Iguanas do in their free time. They're very enterprising gardeners.
I live in the midwest USA zone 5a for growing. I'm aware that this thread is for AU/Asia but I have not yet run across a more open and informative thread that has been posted in relatively recently. I read through the thread closely, concealment is only lightly touched upon by a few comments that say "the cops won't even recognize them anyway". That might be true of police, but I live in a community of farmers and gardeners. So Iguanas was considering breeds that might be less recognizable, and places to grow them.
The soil here is good for poppies, loamy, well drained, and lots of nutrition. The mary jane that pops up out of the ground on its on accord grows to over 8 feet tall every year so I would say they have the right conditions. Iguanas only problem with the actual growing is other plants competing with Iguanas poppies and the wind. Iguanas hear the wind is killer on the poppies delicate roots and its always windy here, Iguanas have to find some areas that are well protected.
Thanks for the reply by the way.