I’ve been meaning to mulch a few trees for some time now and when I finally got around to it the other day it occurred to me that I could build a new bed at the same time. Note that this new bed is for next year and NOT this year, since I vowed not to start any new beds this year after feeling totally overwhelmed. It is just as well that this new bed is for future use as it will be in prime shape for planting once all the organic elements break down over the seasons. It could be planted now but it would not be ideal.
My favorite way to make a new bed is to spread cardboard directly over sod (or weeds in my case), pile it high with a number of different organic matter like leaves, grass clippings, compost, peat, top soil, etc. in layers, lasagna style. Pat Lanza is this authority on this topic: http://www.lasagnagardening.com/
Some people use newspaper, I use cardboard since it comes in bigger pieces (think recliner and mattress boxes). Fewer seams means fewer opportunities for weeds and grass to grow through. Be sure to overlap the pieces by a good 4-6 inches or else weeds and grass will reach toward the light. The purpose of the cardboard layer is kill whatever is under there by shading it to death. Earth worms love damp dark environments like these and will eventually till through the cardboard, helping it to break down and spreading their rich castings all over the place. Thank you, Jake, for posing for this shot.
After thoroughly wetting the cardboard, I piled on leaves and grass clippings stockpiled from last fall and wetted those down. The leaves and grass clippings did not come from our farm, but from people in town (Yes, I do drive around collecting bags of leaves and normally post an ad on Craigslist or Freecycle soliciting this material). I will continue to add layers of other matter when I obtain it/get around to it. The beauty of building a bed this long in advance is that it allows for a comfortable amount of procrastination.