g'day miraje,

put the cardboard under the sheet mulch, collect old newspapers and lay that on the cardboard as well then maybe no digging at all needed.

len

Here is a link that might be useful: lens straw bale garden

I can try that, but I'm not sure I trust the bermuda to go away that quietly.

I should probably clarify that by "bermuda grass lawn", I more mean that it's a neglected backyard patch that's about 40% bermuda, 40% native prairiegrass and grassy weeds, and 20% of just bare soil that nothing will grow in. We don't water or fertilize the lawn, so the grass is really sparse and patchy.

What you propose will work, although I am not all that sure the cardboard would be necessary if the vegetative waste layer is 4 to 5 inches thick. If that layer is only an ince or two then the cardboard, or newspaper, would be needed.
Have you also thought about a barrier at the edge to keep your grasses from growing back into that plot?

miraje, I suggest applying glysophate (Roundup) - at least two times. Don't dig the Bermuda - you won't get rid of it that way. Here are the steps I'd take:

Thoroughly water area. Wait a day, then apply Roundup at normal concentration mixture. Wait up to two weeks - reapply Roundup on anything still looking alive. Wait a week more. Mow area or weed whack as low as possible. Then apply your cardboard and all the wonderful compostables you can find and keep adding to it as more becomes available. Some irrigation will be a help in getting the compostables to break down. Next spring you'll be good to go - if any cardboard remains, just cut through it and plant.

I will buy some steel garden edging from Lowes that I'll hammer in around the beds. It'll be a bit of extra expense, but I absolutely hate pulling bermuda from around my trees and shrubs, and I'll do whatever it takes to keep it out (or at least slow it down!). I'll probably also put down some cardboard and wood chip mulch along the walking paths to choke out the grass next to the beds, too.

I originally thought Roundup would be the only way I could kill the bermuda, but I set up a bed for tomatoes this past spring without it with some decent success. I just dug up the grass, laid down strips of cardboard in the gaps between the tomato plants and laid down some thick mulch on top. I still get some bermuda coming up, but they're not well-rooted and are easy to pull. Adding three or four inches of stuff on top of the cardboard should be enough to keep it under control I think as long as I stay on top of the weeding.

we manage to control nut grass this way as well as kykuya, pretty much anything, the newspaper needs to be thick enough for nut grass usually around 40 pages thick will do the job. with the mulch whatever on top make it at least around 18"s deep deeper if you can. we commonly use paper at around 30 pages thick, don't foget to over lap.

and yes as has been said with this sort of gardening you need to create a weed barrier around and between beds so the newspaper laye needs o over lap with the barrier paper as well.

len

II have seen people spend their money on the glyphosate products because they were convinced it was the end all of plant killers, spray plants with the stuff, and have those sprayed plants grow back because the stuff just is not as good as the ads make it sound, and the people at Iowa State University are finding more and more plants are getting the gene that makes them immune to the stuff.
There is also enough evidence out there to indicate the glyphosates are not as innocuous as the manufacturers would have you believe and they may cause genetic harm to us. If these products cause genetic mutations in lower order insects, reptiles, and mammals why would they not also adversly affect humans, eventually.

At last!!! Someone who realizes that Bermuda grass can be dealt with effectively by adequate mulching! miraje, I had almost become convinced that our Bermuda grass in Maine was a special, spineless, variety that succombed to mulch while no other Bermuda grass in the rest of North America did. It was either that or the people who claim there is no solution except for the application of glysophates don't comprehend mulching.

I put my newspaper on top of my sheet compost and cover it with something pretty. I always wonder why people would cover a weed suppressing mulch like newspaper with weed-supporting materials.

It's nice to hear from someone who actually does it the other way around by composting underneath the newspaper or cardboard. All the googling I've done turns up instructions that just say to throw the cardboard onto the grass and then pile everything on top of it. It takes digging, but I think it's worth it.

miraje, I don't know what part of the country you are in, but here in the oil patch our local welding supply made steel edging for our friends' garden - about 8" wide, finished the ends, and delivered for less than the edging at Lowe's. It is that nice aged rust color and looks great.

My raised beds are built on bermuda too - on top of a 50 year old established bermuda lawn/pasture/weeds. I have very little trouble with it any more, it can be done. I started with cardboard and newspaper 10 years ago and struggled with it until I started mulching like crazy.

Betty, I'm in central Oklahoma, so I'm sure there's probably an outfit like that around here somewhere. I'm all for saving money and getting a good quality product at the same time, so I'll look into it. Thanks for the suggestion!