Plants Calculator
Preset examples only — use your plant label or supplier spacing.
Bed & Planting Inputs
Estimated Plants Needed
Plant Grid Preview
Planting & Purchase Summary
| Item | Quantity | Basis |
|---|
Formula & Worked Example
Square area per plant = spacing²
Triangular area per plant = √3 ÷ 2 × spacing²
Vegetable rows: plant spacing × row spacing
Plants = round up (bed area ÷ area per plant)
Frequently Asked Questions
Which spacing should I use?
Use the specific plant’s label, mature spread or supplier guidance. Presets are editable examples, not universal recommendations.
Why does a triangular grid fit more plants?
The distance between rows is about 0.866 times the plant spacing. This reduces the theoretical area per plant and increases density by about 15.5%.
How are tree rings calculated?
The net planting area is π × (outer radius² − inner radius²). Set inner radius to zero for a full circle. Keep an appropriate clear zone around the trunk.
Is this an exact planting layout?
The count is an area-density planning estimate rounded up. Edge setbacks, paths, irregular shapes and actual row placement can change the count. The preview shows spacing geometry; displayed markers are not used to compute the estimate.
How are spares calculated?
The order quantity is the estimated planting count plus your chosen percentage, rounded up to a whole plant. Spares do not increase the planting density.
Plants Calculator Calculate how many plants are needed to fill a garden bed based on the area and recommended plant spacing. — free online calculator.