Square Foot Garden Planner

Square foot gardening (SFG) is a planting method developed by Mel Bartholomew that divides a raised bed into a grid of 1-square-foot cells, each planted with a fixed number of plants based on the species’ mature size. It maximizes yield in small spaces by eliminating wasted row spacing.

Plants per square foot by mature plant size:

Plants per Square Foot = 12² ÷ Spacing² = 144 ÷ (Spacing in inches)²

Every figure in that table is 144 divided by the spacing squared, rounded to a number of plants that actually fits a square. Nothing else is going on.

Total bed plant count:

Total Plants = Bed Length × Bed Width × Plants per Square

Worked example. A 4 × 8 ft raised bed is 32 squares. Plant it as a mixed bed:

• 16 squares of carrots at 16 each: 256 carrots
• 8 squares of leaf lettuce at 4 each: 32 lettuces
• 4 squares of basil at 4 each: 16 basil plants
• 4 squares of tomatoes at 1 each: 4 tomatoes

Total: 308 plants in 32 square feet, against the 60 to 80 the same ground would hold in traditional rows. The calculator above works one crop at a time, so run it once per crop and add the answers, exactly as this example does.

Mel’s Mix, the standard growing medium

One-third blended compost, one-third peat moss, one-third coarse vermiculite, measured by volume rather than weight. It holds moisture, drains freely, and does not compact into a brick the way garden loam does once it is boxed in.

Succession planting

When a square finishes, replant it the same week. Radishes are done in 25 days, which means one square can carry three or four crops between spring and autumn. This is where square foot gardening actually earns its yield claims, and it is the part most people skip.

Growing upward

Cucumbers, pole beans and small squash will climb a trellis on the north side of the bed, which frees the ground squares underneath for lettuce and other things that appreciate the shade in July.