Start with the in-row range
USU's potato guide supplies the working range: seed pieces 10–12 inches apart within rows 30–36 inches apart. Those figures describe potatoes, not sweet-potato slips. Treat the 10–12 inch range as the source context for seed-piece spacing, and treat the 30–36 inch figure as row spacing that you must plan separately from the within-row count.
The range is not a single instruction to use everywhere. Pick one within-row interval for your plan and label it clearly, so the count and the marks on the ground agree. The example below selects 12 inches, the upper end of the range, for one clearly labeled scenario. That selection is an example choice, not a claim that 12 inches suits every garden.
- Write down the range: 10–12 inches between seed pieces within a row.
- Choose one interval from that range for your labeled plan.
- Record the chosen interval next to the row length and end margins.
Source context: Utah State University Extension
Worked example: one 96-inch row at 12-inch centers
The verified example is a single measured row 96 inches long, with 12-inch centers and 6-inch margins at both ends. The first seed-piece position falls 6 inches from the start, the last falls at 90 inches, and the count is 8 seed-piece positions. The counted item is seed-piece positions, not plants after thinning, not hills, and not rows.
This is a geometrical example of marking positions along one row. It does not establish a crop recommendation beyond the range, and it does not describe an entire garden layout. One row is one row: the 30–36 inch row spacing, paths, hilling space, and access still need their own decisions.
- Measure the row length and both end margins before counting.
- Place the first mark at the end margin, then repeat at the chosen center interval.
- Confirm the last mark sits one end margin short of the row's far end.
- Label the result as seed-piece positions for this one row.
Source context: Utah State University Extension
Separate planting positions from mature-plant planning
The count describes initial seed-piece positions at planting. It is not a count of established plants, and it does not account for later hilling, access, or the mature habit of the crop. USU's guide notes that hilling and access are planned separately, so keep those as separate choices rather than folding them into the spacing number.
Row-to-row distance is also a separate choice. The 30–36 inch row spacing is context for planning adjacent rows, but this guide does not invent a distance for paths, supports, or bed edges. Decide those from your own garden's constraints and record them alongside the row plan.
- Keep the seed-piece count labeled as planting positions.
- Plan hilling and access as separate items, not as part of the center interval.
- Choose adjacent-row spacing separately, using the 30–36 inch context.
- Note any bed-edge or path decisions without assigning them an invented distance.
Source context: Utah State University Extension
Use the row calculator for this exact count
The linked row calculator can count this exact length, center interval, and both end margins, in inches or centimeters. Enter the measured row length, the chosen center interval, and the margin at each end. The calculator returns the number of seed-piece positions for that row.
Check that the units match before relying on the result, and check that the interval you entered is the one you labeled. The calculator counts positions along one row; it does not plan the whole garden, choose row spacing, or decide hilling and access.
- Enter the row length in inches or centimeters.
- Enter the chosen center interval from the range.
- Enter the same end margin for both ends, or the two margins you measured.
- Compare the returned count with your marked row before planting.
Source context: Utah State University Extension
Check your measured example
One measured 96-inch row, with selected 12-inch centers and 6-inch margins at both ends. Count 8 seed-piece positions.
Reference and growing system: USU’s potato guide gives seed pieces 10–12 inches apart within rows 30–36 inches apart. These are potatoes, not sweet-potato slips. Hilling and access are planned separately.
| Quantity | Calculated result |
|---|---|
| Usable row length (in) | 96 |
| Selected center spacing (in) | 12 |
| Margin at each row end (in) | 6 |
| Positions in this row | 8 |
| First center from row start (in) | 6 |
| Last center from row start (in) | 90 |
| What is being counted | seed-piece positions |
The worked example is one 96-inch row with 12-inch centers and 6-inch margins at both ends. The first position is at 6 inches, the last at 90 inches, and the count is 8 seed-piece positions. This is a geometrical marking example within USU's 10–12 inch in-row range, not a whole-garden layout or a crop recommendation beyond the source notes.
Count this row in the spacing calculator ↗Example inputs explain the method. Review the source context, chosen cultivar and actual site before planting or ordering.
Your before-you-plant checklist
- The chosen within-row interval is written down and falls within the 10–12 inch range.
- The row length and both end margins are measured before counting.
- The count is labeled as seed-piece positions for one row, not established plants.
- Row spacing, hilling, access, and adjacent-row decisions are recorded separately.
- Calculator units match the measured row and the labeled interval.
Questions that come up while planning
How far apart should potato seed pieces be within a row?
USU's potato guide gives seed pieces 10–12 inches apart within rows. Choose one interval from that range for your plan and label it. The worked example uses 12 inches for one 96-inch row.
Does the 8-position count mean 8 established potato plants?
No. The count is seed-piece positions at planting along one row. It is not a count of established plants, and hilling and access are planned separately.
Can I use the 96-inch example as my whole garden layout?
No. It is a geometrical example for one row. Row spacing of 30–36 inches, adjacent rows, paths, hilling space, and access must be chosen separately.
Sources & method
Horticultural guidance is linked to its original source and regional context. Geometry and unit conversions are calculated separately. Read how we prepare and check a page.
- How to Grow Potatoes in Your GardenUtah State University Extension