Using Chickens to do the Weeding

[Unmutual]

So I want to get some chickens to do some of the weeding, fertilizing and general cleanup in the annual veggie beds. Here's the problem: the only way I can see to use chickens and keep them contained in a safe environment, is to use 3'(1m) wide beds in long rows, which run perpendicular to their run(and the run being attached to the mini-orchard).
Chickens.jpg

The large rectangle on the ground with the circles is the mini orchard of mostly citrus(I'll be doing a lot of transplanting this winter). The 5 beds are 21'(~7m) long and 3'(1m) wide.

If you notice on the pic, the closest bed shows what it would look like with chickens being allowed into it to do cleanup duty, with the other 4 being closed off to the chickens while production is going on.

My problem is this: I really like the look of keyhole gardens, but they don't seem to lend themselves easily to chickens, or should I say to fencing. Does anyone have a working example of keyhole/mandala gardens with chickens only being allowed into certain areas of the vegetable garden at a time?

I should add that this is a suburban back yard with possums, the odd raccoon(been a while since I've seen one of those) and the possibility of stray dogs. So I want these chickens protected as best as possible while they do their work. These chickens will be treated as pets.

[Adrian1976]

I had thought of making runs off the main chicken pen. Using Reo mesh (Building mesh that is laid into the cement for making stronger concrete) which are about 20ft by 10ft. Making and arch having a bed on either side and a path through the middle. The mesh can be use for climbing veggies or others that need staking. Once finished with get some chicken wire to run along the bottom to keep the chickens in. The end butting up to the main chicken pen has a sliding trap door, and the other has a gate big enough to be able to bring in a wheelbarrow if need be.

[chook-in-eire]

Take a look at this http://www.youtube.com/watch?v=cMBsJ...hannel&list=UL
Permaculture hexagonal vegetable enclosure with integrated chickens. I think this is superb and it might be a suitable and aesthetic solution for your climate.