Dig a trench 30in deep around the perimeter of the bed. line both sides of trench with 2 layers of woven landscape fabric. Inside backfill with a mix of native soil and lots and lots of Preen or a preemergent that is OMRI-approved if it exists. This might do it for 3-4 years, no preemergent hope for 3. Good luck.

Dan

Thanks Dan! that sounds like it may work and would give me a good edge or border to my garden area. Would it really need to be 30 inches? ! Still I love this idea! :) Thanks again...

I overengineer things, but I used to have a house in CA with Bermudagrass, and a landscape design/const. business there, so I've spent a lot of time killing it...as an undergrad a classmate wrote a term paper on it and I edited it for her...the devil's weed. 24 in might get you what you want, but a trencher goes to 36, and fabric is 3ft wide (or 6). Go git 'em.

Dan

There is a machine that will dig and build a concrete curb anywhere you want it. I've seen it advertised in the back of Popular Science and Sunset type magazines as a 'career opportunity.' We had a metal landscape barrier that worked very well. It was only a few inches deep, but then again it was as deep as the underlying bedrock would let it go.

WHY BIG?

Bio Intensive Gardening (BIG) method is a non-conventional form of gardening that with minimum capital and lots of native enterprise can assure needy families of a steady supply of nutritious food - and extra income. It can provide the necessary protein, vitamin and mineral requirements needed by a family of six. It can also reduce the country��s heavy reliance on chemical fertilizers that pose health hazards and wreak havoc on the environment.

BIG CONCEPT

It is an approach to household level food product, deep bed preparation, nutrient recycling, building up of the soil��s biological base, diversified cropping, use of indigenous cultivars or locally adapted varieties and its emphasis on a balanced and integrated ecosystem.

�� WHAT IS BIG?

BIG is a bio-intensive approach as opposed to chemical, it is a form of agriculture in which a small area of land is intensively cultivated, using nature��s own ingredients to rebuild and maintain the soil��s productivity.

�� NUTRIENT RECYCLING

Attempts to maximize the use of plant and animal residues & wastes so as to return to the soil much of what come out from it. Organic matter must be returned to the soil that helped rebuild it.

It can't be any more invasive than Bahia, and that can be controlled with constant hand-pulling. Like any manual weed control, it has to be done super frequently, in which case it isn't difficult.

A few raised beds? Not a problem, no need for 3' deep trenches and the environmental cost of fabric.

Preen or other pre emergents will not stop bermuda. It does however work on Bahia and other seed that may want to germinate. Bermuda will grow over or under most any barrier put in its way. I have had very good luck with weed barrier under mulch. To stop it from encroaching a deep trench could be dug and root barrier installed, a minimum of 1 foot deep. All surface runners must be continually trimmed. Once bermuda is in the bed one must dig along the runners pulling up every last notual. Even 1 left can re sprout. The weed barrier is a lot easier.
Nut grass is the biggest problem around here.

It may well not be possible or desirable, but I killed my entire running-grass lawn with thick layers of card/paper and wood chips.
I think entire is the key word, as there's no lawn left to act as a 'stolon reservoir'...

Some mentally- and emotionally-twisted person came up with the idea that Bermuda would make a good lawn!

Get your shovel, dig straight down inside the edge of the grass and make a hole. When you're down about two feet, stop. Get your hose and wash down the main-lawn side of the hole and look for roots. How deep do they go? That's how deep your barrier needs to be.

Barrier choices: metal (if it rusts, it's temporary); landscape barrier (tiny root tips will work through it, it's temporary); very heavy-duty plastic (lasts a long time when protected from the sun, which it will be in this case).

Using a flat-bladed shovel, dig straight down along your lawn edge, and at an angle from the garden side:

Lawn l../garden side
Lawn l./ garden side
Lawn l/ garden side

Lay your plastic on the angled side of the hole, leaving about a 6" flap above-ground. Backfill the hole. Lay the flap on top of the soil on the garden side, and place flat concrete 8x16" pavers on that flap all along the edge. When the roots hit the plastic, the angle will encourage them to go upward, rather than trying to force their way through the plastic. If they do grow along the top of the plastic (under the pavers), just lift the pavers and cut off. Reasonable vigilance is necessary.

If part of the problem is the neighbor's unmowed grass seed blowing into your garden, use corn gluten meal as a pre-emergent. Research this, and find out what time is best for spreading it in your area -- you do have to get the timing right. The most economical sources are horse-type feed stores.

Note: corn gluten meal and other pre-emergents will also prevent desirable seeds (flowers, vegetables) from sprouting, so you will probably have to start plants in flats or pots and then plant them as seedlings (no longer affected by the pre-emergent).

And thank you, people of the Bamboo Forum, for the solution to this problem! It works just fine!

Sue, in Running Grass Central