A permanent bed system saves the work of building new beds every year and is the most efficient way of farming without a tractor. Working and shaping large quantities of soil every year would otherwise require a tractor in order to work efficiently. For all of the reasons mentioned above, I strongly encourage beginning growers to adopt permanent beds when organizing a market garden.
But this being said, note that such a set way of doing things does require initial onsite preparation. Any major earthmoving project has to be dealt with first. Bumps and dips in the soil surface should be corrected, and if tile drainage is required, it will also need to be installed. When taking over a previously vacant site (e.g., a field or unused farmland), it might inevitably be necessary to use heavy machinery (plow, chisel, rototiller, etc.) in order to bring the land into a “workable” state. A tractor may also be needed to remove any large rocks from the site. When planning for this kind of work to be done, it might also be a good idea to establish an action plan for eliminating persistent perennial weeds such as quack grass, dandelion, and thistle. Repetitive tillage with large disks or harrows might help in that regard.
Once the groundwork is finished, then the real work begins. Depending on the size of the garden, setting up permanent beds may take a few days, or even a few weeks. Creating ours took a while since we had about 180 of them, each 100 feet long. The first thing we did was to mark off the perimeter of each plot (calculated to contain 16 beds of 48 inches center to center). We then used strings to indicate the width of each bed and dug the earth from the pathways onto the beds. It was a lot of work, but we were motivated by the fact that we would only be doing this once.
While laying out the beds, we also added large amounts of organic matter to improve the soil’s quality. In our case, the initial soil was already a desirable gravelly loam soil, and we incorporated about 7 wheelbarrows per 100 foot bed of a compost mix rich in peat moss. We also added lime to raise our pH, which at the time was on the acidic side. We’ve seen other market gardeners add sand to clay-based soils and clay to sandy soils. Along with adding compost, these amendments help improve a soil’s texture.
With regard to the height of the beds, I recommend mounding the soil about 8 inches. Over time the soil will settle, and after one or two growing seasons, the beds may be only 4 to 6 inches high. Raising the beds higher than 8 inches does not produce any significant advantages and only creates more work and higher costs. Many market gardeners seed their pathways with clover, but at our farm, we don’t follow this approach. We use the soil in our pathways to pile on top of beds that have already settled, and we also use the pathway soil to weigh down tarps and floating row cover.