Loam is
soil composed of
sand,
silt, and
clay in relatively even concentration (about 40-40-20% concentration respectively), considered ideal for gardening and agricultural uses. Loam soils generally contain more nutrients and
humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to
till than clay soils.
Loams are gritty, moist, and retain water easily. Loam is ideal for growing crops because it retains nutrients well and retains water while still allowing the water to flow freely. This soil is found in a majority of successful farms in regions around the world known for their fertile land. Loam soil feels mellow and is easy to work over a wide range of moisture conditions.
Different proportions of sand, silt, and clay give rise to types of loam soils: sandy loam, silty loam, clay loam, sandy clay loam, silty clay loam, and loam. A soil dominated by one or two of the three particle size groups can behave like loam if it has a strong granular structure, promoted by a high content of organic matter. However, a soil that meets the textural definition of loam can lose its characteristic desirable qualities when it is compacted, depleted of organic matter, or has clay dispersed throughout its fine-earth fraction.
Fertilization is a separate issue.
If you don't want to have to fertilize, then ass nutritional supplements (mainly manure) to the soil when you mix it.