What to use for Root Maggots?

[Warlord]

This was my first year fighting back against the dreded Root Maggots that were chewing away at the root systems on the Broccoili, cabbage, and cauliflower plants.
I looked them up on the web and the only thing it said was to use pesticide. It didn't give any particular brand natural or not.
What do any of you out there use to combat these little pests. I would prefer a natural alternative. I just had a thought. What if I had a plant that is used for its natural soap making ability and applied some of the soap on the root base of the plants too see if this could get rid of my pest problem. I know, plants don't usually take kind to soap. Although, if I can get my hands on a natural soap making plant I will experiment on a few of our garden plants and record the results.

[MoniDew]

if they are in the roots, that means they are in the soil, right? have you tried diatomacious earth sprinkled all around the soil/roots? It's just the coralized remains of tiny sea creatures (so, it's going to contribute some calcium to your soil) and it cuts to shreds little soft bodies, like maggots. My husband works at a swimming pool supply retailer, which gives us a good supply of the stuff. In that industry it is used as filtration material.

[Warlord]

Thanks Monica, I will definatly be buying some this growing season. This will work far better than my complicated Idea.
Looking fabulous by the way.