Calculators / Garden and firewood
Plant spacing calculator
Measure the bed and read the spacing off the tag. You'll get the plant count, and the flats if they come by the flat.
Updated · How we check our numbers
Plants to buy
47 plants
40 sq ft at 12 in apart on a staggered grid. A square grid would take 40.
- Bed
- 40 sq ft
- Plants
- 47
Estimate for planning only, not professional advice. Check the manufacturer’s instructions, your local code and a licensed professional before you buy, build or install. Use at your own risk. Terms.
bed = 10 × 4 ft = 40 sq ft
each plant = (12 ÷ 12)² × 0.866 = 0.866 sq ft
plants = 40 ÷ that = 47, rounded up
Use the spacing on the plant tag, center to center. It allows for the plant’s full size, so beds look sparse the first season.
Keep the outer row half the spacing (6 in) in from the edge. Long, thin beds hold a few fewer plants than the math says.
How we work it out
Each plant gets a patch of ground the size of its spacing.
square grid: plants = bed sq ft ÷ (spacing ft)²
staggered grid: plants = bed sq ft ÷ ((spacing ft)² × 0.866)
Staggered rows sit closer together (0.866 of the spacing, from the triangle each three plants make), so the same bed takes about 15% more plants and fills in with fewer gaps. Use the center-to-center spacing on the tag.
Not sure of the size?
When to plant
For the bed
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