I have to agree with nycynthias and say that cardboard is the way to go. Those fibrous roots will, when the plants die, provide a great deal of organic matter in the soil which is a great thing indeed. My approach would be thus: - Cover the whole area with a thin layer of compost. If you can't get that much compost, manure, or a complete organic fertilizer will work. Then, take a very sharp spade and make some deep cuts in a random pattern. Ideally you would turn the soil over, but if that is too much work for the area, then just make some deep cuts and work the shovel back and forth. Get that compost/fertilizer incorporated. At this point, you are trying to break up the root network, introduce some oxygen and some organic matter. - Next, lay down three to four layers of newspaper, wetting each one with a spray hose as you put it down. - Then, over top of that, lay down a good thick layer of cardboard. Not knowing what weed it is, I can't say one or two layers, but one should do it, two would for sure. - Your raised bed will go right over top of that. Regardless of whether you are building a framed/enclosed bed, or simply "hilling" to create a rise, you are going to have to import soil. Get a good quality, local triple mix and incorporate the complete organic fertilizer used above. What is happening underneath all of the newspaper and cardboard? Well, the weeds will experience a boom in growth having their roots aerated and the soil fertilized. The stems will grow in an attempt to reach light. However, with that much weight on top of them and the thick layers of cardboard and newspaper, the stems will not penetrate (at least not most of them). Eventually, their tissue will blanch white in response to the lack of light, and the sugars and carbohydrates will break down fairly quickly. Eventually, the weeds will die and be eaten by a whole host of microbes and worms. All of that eating produces waste, and that waste is what we all want in our soil and does such a great job providing nutrients to the vegetables. Hope that helps. Michael

There's another weed/wildflower in my garden that's really pretty in some of its permutations. I've been calling it a "wild geranium" because the leaves sort of look like geranium leaves. I finally found it on the net and it's actually mallow. Several types, to be specific. The prettiest are the "tree mallow" or "hollyhock mallow," which grow to several feet tall (if tops aren't pinched off) and have relatively large, brightly colored (pink, purple, or 'striped') blossoms. Then there is the "common mallow," which has much smaller, white or pale pink flowers and usually spreads out over the ground. Pretty sure these are hardy annuals, not perennials, and it's pretty easy to pull up the unwanted young plants in the spring when the ground is moist. I have a friend whose back yard was abundant with the large, colorful varieties, and I found it easy to harvest the seeds. Mallow is also a widely used medicinal plant/herb. Here are some pics: http://www.nerc.ac.uk/publications/latestpressrelease/2005-42puffins.asp http://www.santabarbarahikes.com/flowers/index.php?action=show_item&id=257&search= http://www.cwss-scm.ca/Weeds/images/Mal2-common-mallow.JPG http://images.google.com/imgres?imgurl=http://212.84.179.117/i/Mallow.jpg&imgrefurl=http://212.84.179.117/list.htm&h=300&w=189&sz=17&hl=en&start=11&tbnid=Qhhpso2ryidvJM:&tbnh=116&tbnw=73&prev=/images%3Fq%3Dmallow%26svnum%3D10%26hl%3Den%26lr%3D http://212.84.179.117/i/Musk-mallow.jpg http://images.google.com/imgres?imgurl=http://aco.ca/acorns/_images/perennial_gardens/Wild-Mallow-Blooms-July-thr.jpg&imgrefurl=http://aco.ca/perennial_gardens.html&h=335&w=350&sz=46&hl=en&start=64&tbnid=bSmecGCNXHPMpM:&tbnh=115&tbnw=120&prev=/images%3Fq%3Dmallow%26start%3D54%26ndsp%3D18%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DN http://www.nerc.ac.uk/publications/latestpressrelease/2005-42puffins.asp http://thebegavalley.com/uploads/tx_steverplantgallery/Malva_parviflora_04_small-flowered%20mallow.jpg http://www.easywildflowers.com/quality/cal.di1.jpg http://images.google.com/imgres?imgurl=http://www.naturedirect2u.com/Medicinal%2520herbs/mallowpic4.jpg&imgrefurl=http://www.naturedirect2u.com/Medicinal%2520herbs/mallowherb.htm&h=387&w=368&sz=42&hl=en&start=137&tbnid=8iP2FaB60KZ36M:&tbnh=123&tbnw=117&prev=/images%3Fq%3Dmallow%26start%3D126%26ndsp%3D18%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DN http://images.google.com/imgres?imgurl=http://www.garten.cz/images_enc/00058/00058C1.jpg&imgrefurl=http://www.garten.cz/encyklopedie.php%3Flng%3Den%26encid%3D58&h=200&w=150&sz=13&hl=en&start=234&tbnid=9y9Rq8Mivh7YuM:&tbnh=104&tbnw=78&prev=/images%3Fq%3Dmallow%26start%3D220%26ndsp%3D20%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DN

All of the site preparation info above is good. Do it. Get rid of everything with Roundup (or any glyphosate herbicide). Then, next fall, in Nov or Dec, after the ground has cooled and nothing will germinate, spread an appropriate mixture of native grasses and forbs ("wildflowers") on the site. Let the winter rains and frosts work these into the ground (unless its sloped). The problem (as IÂve mentioned in several previous posts some time ago) is that "widlflowers" are never, ever found by themselves in nature. In every meadow example there are supporting and weed-suppressing grasses surrounding each forb. The reason your patch looked so bad was because it was a weed haven. If you can, at any time, look down and see bare soil (as you could when the flowers were there), weeds will take over the site. Consequently, youÂve got to plant proper grasses along with the flowers. And you need to plant a lot more grasses than forbs. You have a quarter-acre site, and I strongly recommend the planting of the grass below at a 10-15 lb/acre rate. ThatÂs about 4 lbs. The forbs are secondary and can be planted in ounce-sized quantities. But the key to accomplishing all that you wish is the proper selection, planting, and management of the supporting grasses. And there is really (in my experience  and IÂve done a lot of these professionally) only one grass to consider, little bluestem. It will provide all that you want: support for forbs, no requirement for water, fertilizers, or sprays, is gorgeous in all seasons (especially fall and winter in a remarkable russet red), and if properly managed, will persist until the next glacier gets here. The variety of little bluestem (Schizachyrium scoparium) to use is ÂBlaze. A number of Midwest native grass suppliers have it. I recommend Ohio Prairie Nursery (http://www.ohioprairienursery.com/). They can supply this variety. Spread the seed, mixed with sand, over a light snow in Nov or Dec. By this, you can see where this fluffy seed lands. In spring and summer, simply mow the entire area at 3-4 inches. The little bluestem grows downward the first year or two, and is hardly visible (except to an experienced expert). This first-year mowing keeps any weeds from getting the upper hand. In the second year, mow again in May and June, but then back off and let the little prairie grasses begin to shoot up. You will see very little and believe that youÂve wasted your time and money. But after Oct frosts you will see a scattering of reddish small clumps. In the third year, these will become nice clumps of grass of wonderfully thin leaves that toss nicely in the wind. The forbs will be growing between these little bluestem clumps. In the fourth year you will have what you envisioned, a "wildflower" meadow (not a garden  gardens require constant weeding, watering, and other continual messing -with) If you think you are planting a Midwestern prairie in New England, you are correct. But as it happens, most of the uplands surrounding what later became Boston was a little bluestem prairie meadow landscape in the early 1600s at the time of settlement. New Englanders erroniously believe that all of the region was ancestrally all in dense forest. Not so. Many large areas, especially near the Coast, were little bluestem prairies created by annual Native American landscape fires. The heath hen, a bird which became extinct on MarthaÂs Vineyard in the 1930s, was actually a New England version (same species, different subspecies) of the Midwestern prairie chicken. Unless you plant some native prairie grasses, you will not be able to accomplish all that you envision. The finest thing would be to attempt to restore this rare 16th century habitat.

I'm sorry if I'm repeating what others have said but I have a plot in a community garden and have thought about this. My community garden is 30+ years old so I don't know how they prepared the soil way back then but now when a plot is turned over to a new gardener it is up to the new gardener to till and amend the soil. This turns out really very well although sometimes it means dealing with a garden where the soil was amended very little if at all and the weeds grew rampant or if you're lucky the previous plot holder took care of the soil. In your community garden project, if you want to till and amend the soil for your first gardeners you should get as much good quality non-manure compost as you can afford, till that in then let your gardeners add manure or anything else they want later on. I think this will get the soil ready to plant without a lot of cost. If the individual gardeners want to test the soil in their garden plots and add amendments let them do it themselves; this is an important part of being a gardener and very satisfying. Often landscape suppliers will offer discounts to community gardening projects and, at least in my area, the municipal sanitary service makes cheap compost available made from the garden waste they've pick-up from the green bins... Good luck with your garden project...