Plant Spacing Calculator
How many plants fit a bed at the spacing on the label, in square rows or staggered triangular rows, which fit about 15% more.
Result
Buy 60 plants
Counts round down: a plant that does not fit is not planted.
- Rows
- 7
- Plants in a full row
- 9
- Spacing between rows
- 15.59 in (39.59 cm)
- The other layout would fit
- 54
- Plants per square metre
- 5.524
- Plants per square foot
- 0.5132
https://calcgallery.com/landscaping/plant-spacing-calculator/
Results are estimates for planning only. Actual needs vary with site conditions, products and workmanship. Always confirm quantities with your supplier and follow local building codes and manufacturer instructions. Read the full disclaimer
How to use the Plant Spacing Calculator
- Enter the bed's length and width, and the spacing from the plant label.
- Choose square rows or staggered triangular rows, and any gap to leave at the edge.
- Read how many plants fit, the rows, and how many the other layout would take.
Counting the rows
square plants in a row = ⌊usable length ÷ spacing⌋ + 1 rows = ⌊usable width ÷ spacing⌋ + 1triangular rows = ⌊usable width ÷ (spacing × √3/2)⌋ + 1 alternate rows are shifted half a spacingThe usable length and width are the bed less the edge gap on both sides. Counts round down: unlike bags or boards, which you round up to have enough, a plant that does not fit simply is not planted.
Why triangles pack better
In a square grid each plant has four close neighbours and gaps at the diagonals. Shifting alternate rows closes those gaps, like oranges stacked in a crate. Every plant keeps the same distance to its neighbours, but the rows move closer, so the same bed holds more.
With your numbers
- Triangular rows are spacing × √3/2 apart, alternating full rows and rows offset by half a spacing
Quick reference
Counts round down: a plant that does not fit is not planted.
| Job | Plants that fit |
|---|---|
| 12 × 8 ft at 18 in, square | 54 |
| 12 × 8 ft at 18 in, triangular | 60 |
| 10 × 10 ft at 12 in, square | 121 |
| 10 × 10 ft at 12 in, triangular | 126 |
| 12 × 8 ft at 18 in, 9 in edge | 40 |
| 4 × 2.5 m at 45 cm | 63 |
Common questions about the Plant Spacing Calculator
- How many plants do I need for my bed?
- Divide each side by the spacing, add one for the plant at the start of the row, and round down. A 12 by 8 foot bed at 18 inches fits 9 plants along and 6 rows across in a square grid, 54 in all. The page counts exactly this way, so the result is the number you can actually plant.
- What is triangular spacing?
- Rows set closer together, each shifted by half a spacing, so every plant sits the same distance from its six neighbours. The rows are spacing × 0.866 apart instead of a full spacing, and the same area holds about 15% more plants, 2/√3 times as many per square metre. Use it for ground cover and hedging, where you want the bed to fill in evenly.
- Should plants go right up to the edge?
- Usually not. Setting the outer plants half a spacing in from the edge gives them the same room as the rest. On a small bed it costs a noticeable number of plants, which is why the page asks for it.
- Where do I find the spacing?
- On the plant label or seed packet. It depends on the species, the variety and how quickly you want the bed to fill, so the page supplies no spacing of its own.