Plant Spacing Calculator: How Many Plants Do I Need
Work out how many plants a bed needs. Enter the bed length, width and the center to center spacing, then choose a square grid or tighter triangular packing.
How to calculate plant spacing
- Enter the bed length and width in feet.
- Set the spacing between plants in inches, from the plant tag.
- Pick a square or triangular layout and read the plants, rows and columns.
Examples
10 by 4 ft bed at 12 in spacing
Length 10, width 4, spacing 12 in, square
11 columns x 5 rows = 55 plants
Frequently asked questions
How do I find the right plant spacing?
Use the spacing on the plant tag or seed packet, which is the recommended center to center distance at maturity. If a range is given, the smaller number gives faster cover and the larger number gives each plant more room.
What is the difference between square and triangular spacing?
Square spacing lines plants up in a grid. Triangular spacing offsets every other row so plants nest together, fitting about 15% more in the same bed while keeping the same distance between neighbors.
Why is a plant placed at each end of the row?
Spacing is measured center to center, so a 10 ft row at 12 in spacing has plants at 0, 1, 2 ... 10 ft, which is 11 plants. The calculator adds one to the number of gaps to count both ends.
Does this work for ground cover and bulbs?
Yes. Any plant set on a regular grid works, including ground cover, bulbs, annuals and vegetables. Just enter the recommended spacing in inches for that plant.
Should I buy a few extra plants?
It is wise to buy a small surplus to replace any that fail to establish and to keep the layout even at the edges. The triangular option already accounts for tighter packing.
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