Square Foot Gardening Planner Calculator Guide
Use this square foot gardening planner to calculate how many plants fit in a raised bed divided into 1-foot squares. Enter bed length and width in feet and select a crop to get total square feet and recommended plant count based on standard SFG spacing density.
How to use the square foot gardening planner
Enter raised bed length and width in feet (classic SFG beds are 4×4 ft). Select your crop from the preset list with plants-per-square-foot spacing.
Results show total bed area in square feet and total recommended plants for that crop across the bed.
Square foot gardening formula
Total square feet = Length (ft) × Width (ft). Recommended plants = Total sq ft × Plants per square foot.
Each square foot is planted at a fixed density — 16 carrots per square (3-inch spacing), 9 spinach or bush beans (4-inch), 4 lettuce (6-inch), 1 tomato or pepper (12-inch).
- Plants = bed sq ft × plants/sq ft
- 16/sq ft: radishes, carrots, onions
- 9/sq ft: spinach, beets, bush beans
- 4/sq ft: lettuce, chard, strawberries
- 1/sq ft: tomato, pepper, broccoli, kale
Worked example
A classic 4 ft × 4 ft square foot bed planted entirely with loose-leaf lettuce at 4 plants per square foot.
Total sq ft = 16. Recommended plants = 16 × 4 = 64 lettuce plants across the bed.
Square foot gardening basics
Divide beds with a physical grid (lath, twine, or vinyl) so each square is planted separately. Mel Bartholomew's method emphasizes intensive spacing, raised beds, and Mel's Mix growing medium for beginner-friendly yields.
Mix crops within one bed — alternate squares of fast radishes and slow carrots to maximize space.
Planning tips
Tall crops (tomatoes, corn) go on the north side so they do not shade neighbors. Use succession planting to replant squares as harvest finishes.
- See plant spacing calculator for row-layout alternative.
- Use seed quantity calculator for tray sowings.
- Pair with raised bed cost and soil mix calculators for new beds.
- Refresh one square at a time for continuous salad harvests.