What do Black Soldier Flies Eat?

I will receive my first shipment of black soldier flies this week.  I have been researching them and think they will make a good addition to my chicken feed and help offset the cost of store bought feed.  
I realize they eat just about anything from dog/cat/human manure, all table scraps, meat, and dairy.  I think I could produce about 1 or 2 lbs of table scraps per day which would give me a small but continuous source of BSF larvae.
If I want to start offsetting my chicken feed cost I will need to produce a lot more BSFL.  I won't be able to do that on my current table scrap production.  I was wondering if anyone has successfully fed their BSF edible weeds. I am thinking wild carrots, burdock roots, burdock leaves, rhubarb leaves, wood land sunflowers, squash vines, amaranth leaves, and other green items.  All info I read says not to feed them grass because it is hard to digest.  I am inclined to think that anything a human would eat a BSFL would eat so all the wild edibles that aren't super tasty would be good feed for the BSFL.
Anyone have any experience with growing or making food for BSFL to increase BSF production?  I don't want to harvest pig manure or dig through the landfill like the large BSFL factories.
Thanks for any insight.

Anthony

I also realize I live in MN where they will not make it through the winter.  That is another problem in itself that I will try and address also.

They won't be happy on a lot of green vegetable matter.  Think of them as omnivores, not herbivores; but they are great about being able to extract nutrients from nutrient-dense wastes like manures.   I've never had a problem keeping mine fed...the problem is building up a colony of sufficient size to be useful between a chilly winter and a very hot dry summer.  Where I used to live in Georgia it was easy.  Vile stuff like human and pet manure is an important staple, as well as any food residue that has gone thoroughly moldy and rotten. (Most kitchen trash is more efficient fed to the chickens directly first, and then routh their manure to the soldier flies if you can gather it frequently and easily.    Then there are mainstream society's wastes....coffee grounds come to mind first.  Many coffee shops, including Starbucks, often give away used coffee grounds for free.  BSF thrive on this as a sizeable part of their diet, and surplus grounds can be spread out and sun-dried and then rehydrated in batches for later use.  Dead animals and roadkill, and poisonous wild mushrooms can go in to them too.

Ditto what Alder said.

Give them Chinese food take-out leftovers.  Edible weeds, not so much.

They like anything gooey and starchy from the back of the refrigerator.  Finally -- a good use for McDonalds!  If you have access to a school cafeteria, they throw away hundreds of pounds of leftovers daily.  One 5-gal. pail of cafeteria slop will feed your bin for a week.

One thing that I found that grows readily in my food forest that they eat is sweet potatoes.  My sweet potatoes are practically invasive and come up year after year.  If I haven't got much food for the BSF larva, I'll dig up a bunch of sweet potatoes and toss them whole into the cob oven.  I'll build a small fire and bake them till they are soft.  Then I feed the potatoes to the BSF larva.  It's better than them going hungry.

Road kill is always a treat for them.  Rodents and pest animals are easy enough to catch.  If you butcher your own chickens, all the blood, guts and feathers go into the bin.

I need to do something with the manure from 3 cats. Currently it goes into landfill, along with pine pellet litter and all the urine. Can BSF use some or all of that? When you feed them manures, is it moist and smelly? iI'd feed them some green waste and table scraps too. can that be countered by some other feed stuffs? I don't really have a use for the larvae, although I might feed the birds with them. I am looking for compost too, but mostly dealing with the litter boxes.
Also, the Separett toilet yields semi-dry packets of partly composted humanure, if I read the website right. Can BSF use that without too much stink?
All thoughts on this appreciated.

BSF larvae have their own distinctive but not unpleasant smell, and they work so rapidly that stinky garbage or poop quickly disappears, in my experience.   They do stop working when it is cold, but stinks usually calm down in the cold also.

I would add that they seem to like nuts. Mine did real well on moldy chestnuts (spiny outer and all). I suspect they would do well on acorns / hickory / black walnut too. Might have to add moisture from time to time