Soil for Individual Beds
Individual beds at Patchen Community Square are 4' x 8' and will need about 34 cubic feet of soil (just over 1 cubic yard.) You can make your soil from scratch or by purchasing bags. If you were to use, for example, "Miracle Grow" mixed garden soil, each bag is 1 cubic foot. So you would need 34 bags. Soil is a biological process that takes time. Ideally, you would have a few weeks to let your soil settle and breath. In any case, you should fill your bed and give it a full night to breath and settle.
You can and should read this to learn more about soil:
6-9 cubic foot of composted manure
1/2 lb of plantone (organic fertilizer)
3 - 25 lb bags of sand
1/2 cubic foot of vermiculite
1/2 cubic foot of peat moss
and otherwise, just topsoil from the site, to fill up.