Spacing is on the plant tag for a reason
Plant count is bed area divided by the square each plant needs at maturity: a 12-inch spacing gives one plant per square foot. Cramming annuals together looks full on day one and becomes a fungal problem by July — the tag's mature spacing is the number to enter, not the size the plant is today.
Stagger for fullness
Rows planted in a grid show gaps; <strong>offsetting alternate rows</strong> (triangular spacing) covers the same area with the same plants and reads much fuller. For borders, run the math per plant type separately, then add — mixes need their own counts.