I may soon be one of the people in charge of a Community Garden in our town. I would like to take advantage of local resources to build all the garden areas from available organic material. This would be wood chips, grass clippings, cafeteria leftovers, farm manure/straw, etc. It is now the end of January in Zone 6 and I am not sure how soon the rest of the group is expecting a workable garden but I have a few questions that need attention independent of the time frame. To save time and space, I thought about having the compost areas and the garden areas be the same areas. My question is how to go about using the above mentioned materials and converting the compost area to a garden area even though the compost is not fully decomposed? I assume I would not be growing directly into the aging compost? Would it be better to till the ground underneath the area first? If tilling beforehand, should some of the organic material be laid down first and tilled in? Thank you very much.
Opinions differ. There is a school of thought called "Lasagna Gardening" where they never till, just lay down cardboard and then many layers of thing that I put in to my compost heap. They garden right in that composting stuff (I guess, from what I read).
Searching on "Lasagna gardening" should let you find threads and websites like that. People I respect say it works great. I THINK it is best when your soil is so awful that killing weeds and turning it over would be a lot of work,. and still produce only rotten, rocky soil or clay. It is a no-till method.
I'm very traditional and have not tried the Lasagna method myself. I compost in compost heaps. I try to chip or shred any wood in my heap as fine as possible so that it breaks down faster. If I had wood chips, I would use them as mulch for a few years and then compost them.
Meanwhile I turn and screen the clay, dig trenches and raised beds, and mix in amendments and compost and organic matter to try to get it to drain. Then I scratch my best compost into the top few inches to concentrate it in the upper root zone, knowing that it and its microbes will leach down .
Perhaps a compromise for you would be to compost in heaps or sheets, right where you plan to garden, until soil is dry and warm enough to till. Then turn that under, because the soil can probably use the help! That will give your plants' roots access to a real soil root zone. Then follow the rest of the Lasagna plan with yet more organic material on top of the soil, if you like that system .
I never turn fresh sawdust or wood chips UNDER the soil, I only lay them on top of a bed or walkway as mulch and turn them under a few years later. Or try to chip them smaller, and then compost them in some pile that I expect to cook for many months, They say and I believe that wood is "all carbon, no nitrogen", so that if you mix it into the soil, microbes eat wood and and suck up ALL the nitrogen in your soil, out-competing your plants' roots. That's called "nitrogen deficit", and its why wood is better composted, or used as mulch. When it sits on the surface as a "top-dress mulch", unmixed with soil, the microbes can't simultaneously feast on it and your soil's nitrogen.
Remember never to work the soil or even walk on it too much when wet. I forgot that once years ago and made a lunar landscape of concrete.
Do you have any slope top your soil? Or is it loose enough that heavy rains can drain straight down and out of your top layers? You might need to consider where water will drain to once you have beds with loose soil below grade. At worst you might have to make raised beds or sunken walkways to provide drainage (run-off).
However, that "worst thing" is also a great thing. Say you have someone who will plow so as to throw soil out of the walkways, and up onto slightly raised beds. If this is large-scale, walls on the raised beds would be too expensive. Just make the beds with sloped walls, so they are flat-topped berms.
You'll have to pick your angle carefully if there is any slope or grade: I think that "mostly along a contour line" is best, with enough angle that water that drains out of the raised bed and into the walkway, will drain gradually downhill ALONG the walkway.
Cover the walkways with wood chips if you have enough. After plants are up, you can mulch the beds with wood chips.
With narrow beds no more than 3 feet wide (4 at most), people never need to walk ON the beds. They can reach the bed form one or both sides. And the sunken walkway plus raised beds means q12" to 16" less that people have to bend over while sowing, transplanting, weeding and harvesting. Will old geezers like me be growing there? They'll love "less bending". Give them the 3-foot-wide beds.