About the square foot garden calculator
Square foot gardening divides a bed into a grid of 1-foot squares and plants each square at a set density: one large plant, four medium, nine small, or sixteen very small ones.
Enter the bed size to count the squares. Add a soil depth if you’d also like to know how much soil fills it.
How to use this calculator
- Enter the inside length and width of the bed.
- Keep the square size at 1 ft (or 30 cm), or change it if you use a different grid.
- Optionally add soil depth to estimate fill.
- Use the plant totals to plan seed and transplant purchases.
Worked examples
- 4 × 8 = 32 squares
- At 4 per square: 128 plants
- Soil at 6 in: 16 cu ft
32 squares; 16 cu ft of soil at 6 inches deep.
Measurement guidance
Plants per square
Large crops like tomatoes and peppers typically take one square each. Lettuce often fits four, beets nine, and carrots or radishes sixteen. Check a planting chart for your crops.
Bed width
Beds about 4 ft wide let most people reach the center from either side without stepping in.
Frequently asked questions
How many squares are in a 4 × 8 bed?
32 one-foot squares.
How deep should a square foot garden be?
Many square foot gardens are about 6 inches deep, with deeper sections for root crops. Deeper beds hold more moisture.
Can I use metric squares?
Yes. Switch to metric; a 30 cm square is a common equivalent.