Plant Spacing Calculator: How Many Plants Do I Need

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 to size up.

Square spacing lines plants up in a straight grid. Triangular spacing offsets every other row so plants nest into the gaps, fitting about 15 percent more in the same bed while keeping the same distance between neighbors.

Spacing is measured center to center, so a 10 ft row at 12 in has plants at 0, 1, 2 and on up to 10 ft, which is 11 plants. The tool counts the gaps with floor(length in inches / spacing) and then adds one to include both ends.

It first counts the square grid for your bed, then multiplies by 1.15 and rounds up. This is a practical estimate rather than a full offset geometry, so treat the triangular figure as a close upper bound and buy to it.

Bed length and width are entered in feet and spacing is entered in inches, matching how beds and plant tags are usually described. Internally it converts feet to inches so the two never clash.

Yes. Any plant set on a regular grid works, including ground cover, bulbs, annuals, perennials and vegetables. Just enter the recommended spacing in inches for that plant and read the count.

It is wise to buy a small surplus to replace any that fail to establish and to keep the edges even. The triangular option already leans toward tighter packing, so a square estimate leaves a little more room for spares.

The calculator assumes a rectangle. For an odd shape, split it into rectangles, run each piece separately and add the totals, or enter the bounding rectangle for a slightly generous count.

No. The math runs entirely in your browser, so your bed sizes and plant choices never leave your device and nothing is uploaded to a server.