Formula
Plants per row = row length ÷ (spacing in feet), rounded down. Example: 20 ft row at 12 in spacing = 20 plants. For a bed with several rows, use the plant spacing calculator instead.
How to use it, step by step
Enter the row length in feet and the spacing in inches from the seed packet. The calculator divides row length by spacing in feet and rounds down. Use it for single rows — for a whole bed, use the plant spacing calculator instead. Leave a path at each end of the row for access, and do not count that path as planting length.
Worked example in detail
A 20 ft row at 12-inch spacing holds 20 plants. At 6-inch spacing, the same row holds 40 plants. At 18-inch spacing, it holds 13 plants (20 ÷ 1.5 = 13.3, rounded down). Rounding down matters: the 14th plant at 18-inch spacing would not fit without crowding the last plant into the path.
What affects row planting in practice
Row orientation affects light: north-south rows give more even light to both sides of the row than east-west rows in many climates. Wide rows or beds reduce the number of paths needed, but make the middle hard to reach. For crops harvested repeatedly, leave a wider path than you think you need — you will walk it many times with a basket.
Frequently asked questions
What if my row is not straight?
Measure along the row, not the straight-line distance between its ends. A curved row is longer than its endpoints suggest.
Should I plant in single or double rows?
Double rows fit more plants per path, which suits small gardens. Single rows are easier to weed and harvest, which suits larger gardens and crops that need frequent picking.
How much path space do I need?
At least 18 inches for comfortable walking, 24 inches if you carry tools or a wheelbarrow. Narrower paths are cheaper in space but harder to use all season.