Plant Spacing Calculator
Work out how many plants a bed needs from its size and your plant and row spacing, for a square grid or a denser triangular layout. Calculates in your browser.
Plants needed
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Show the math
Each plant sits half a spacing in from the edge, so it has its full spacing on every side:
per row = ⌊length ÷ plant spacing⌋
rows = ⌊width ÷ row spacing⌋ (square grid)
A triangular layout puts every plant at the corner of an equal-sided triangle, one plant spacing from each neighbor: rows sit plant spacing × 0.866 (√3 ÷ 2) apart, starting half a spacing in, and every other row shifts half a plant spacing, so those rows can hold one fewer plant. The row spacing applies to the square grid only.
A triangular (offset) layout staggers each row, packing in roughly 15% more plants for the same spacing, good for ground cover. All math runs locally in your browser.
What this does
A plant spacing calculator works out how many plants a bed needs from its size and your plant and row spacing, for a square grid or a denser triangular layout.
How to use it
- Enter the bed length and width.
- Set the plant spacing, and the row spacing for a square grid.
- Choose square or triangular layout.
- Read the number of plants.
How it works
Each plant sits half a spacing in from the edge, so plants are fitted along the length and width at your spacing. Triangular spacing offsets every other row and keeps every plant one spacing from its neighbors (rows 0.866 × spacing apart), packing in about 15% more on a large bed.
plants = ⌊length ÷ spacing⌋ × ⌊width ÷ row spacing⌋
Understanding your result
The count assumes even spacing across the whole bed; a triangular, offset layout fits roughly 15 percent more plants in the same area than a square grid. Use the spacing for the plants mature size rather than the seedling, since crowding later reduces airflow and yields.
Example
A 4×8 ft bed at 12-inch spacing holds 32 plants in a square grid, one per square foot.
Last updated .
Frequently asked questions
What is triangular spacing?
Offsetting every other row so plants sit in the gaps packs in about 15% more plants at the same spacing, handy for ground covers and intensive beds.
How is the count worked out?
It fits plants along the length and width at your spacing, keeping half a spacing between the outer plants and the edge, then multiplies rows by plants per row.
Should I round the bed size down?
Use the real planting area. Leave room at the edges if mature plants will spread, or reduce the spacing to fill in faster.
Is anything stored?
No. Everything is calculated locally in your browser.
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