It’s not about curb appeal, but the way you backfill a foundation makes a difference to a home’s real value. Good backfill should be well-compacted and stable to ensure it won’t settle over time and won’t apply too much pressure to the basement walls. It should be coarse, well-draining material to help keep the basement dry. Site soils are fine if the natural soil in the area is mainly sandy or gravelly, but don’t use the existing soil from the site for backfill if it contains clay or organic material.
Whatever the material, backfilling a basement foundation puts a momentary stress on the walls. Let the concrete cure for at least a week before backfilling (28 days is best). Place and compact the backfill carefully in partial lifts—don’t dump it all in at once. And if you have to backfill before the floor system is framed, support the walls first with sturdy diagonal bracing.