Read the source range in its field-production context
The linked guide gives two ranges: 12 to 18 inches between collards within a row, and 24 to 30 inches between rows. Both describe field production of mature leafy greens. The within-row figure is the one used to place plants along a single row. The between-row figure is a separate decision about how adjacent rows relate to each other.
A range is not a single recommendation. Choosing 12 inches packs plants more closely; choosing 18 inches leaves more space between them. Either choice stays inside the range, but the choice should be made deliberately and recorded so the plan can be checked later. The source does not say which end of the range suits a particular bed, soil or harvest schedule, so do not treat one number as universally better.
- Write down the source range: 12 to 18 inches within rows, 24 to 30 inches between rows.
- Label the range as field-production guidance for mature collards.
- Choose one within-row value and note why you chose it for this plan.
Source context: Utah State University Extension
Choose one labeled scenario and mark the row
For a clearly labeled example, this guide uses 18-inch centers along a measured 144-inch row with 9-inch margins at both ends. That is a geometrical example of placing field-production positions, not a claim that 18 inches is the best spacing for every collard crop. The 18-inch value sits at the wide end of the within-row range.
The counted item is field-production positions, meaning the points where established plants would sit along the row. It is not a count of seeds, seedlings, thinnings or harvested leaves. Sowing, thinning and initial planting involve different decisions from the final established spacing, and the source range describes mature field production rather than seed or transplant spacing.
- Measure the row length and record it in inches or centimeters.
- Select a center spacing within the 12 to 18 inch range and label the scenario.
- Set an end margin at each end of the row and record both margins.
- Mark each center point along the row and count the positions, not the seeds.
Source context: Utah State University Extension
Work through the 144-inch example
With a 144-inch row, 18-inch centers and 9-inch margins at both ends, the first center falls at 9 inches and the last center falls at 135 inches. Counting the points at 18-inch intervals between those two centers gives 8 field-production positions. The margins keep the first and last positions away from the row ends.
The linked row calculator can count this exact length, center interval and both end margins, in inches or centimeters. Use it to check the arithmetic for your own measured row. The calculator counts positions along one row; it does not decide the between-row distance, the bed width or the rest of the garden layout.
- Enter 144 inches as the row length.
- Enter 18 inches as the center spacing.
- Enter 9 inches as the margin at both ends.
- Confirm the result is 8 field-production positions and that the first and last centers match 9 and 135 inches.
Source context: Utah State University Extension
Decide the rest of the layout separately
One counted row is not an entire garden layout. The between-row distance of 24 to 30 inches from the source must be chosen separately, and access paths, bed edges, supports and the mature habit of adjacent plants all affect how rows sit together. The source does not supply distances for paths, bed widths or supports, so those choices need their own reasoning rather than a number borrowed from the within-row range.
Record the chosen within-row spacing, between-row spacing, and access space for collards so the plan can be reviewed before planting. If you sketch positions on a grid, treat it only as a drawing aid and keep the collard spacing values explicit.
- Choose a between-row distance within the 24 to 30 inch range and record it.
- Mark access paths and bed edges separately from the collard positions.
- Note any supports or adjacent mature plants that affect the layout.
- Review the full sketch against the recorded values before planting.
Source context: Utah State University Extension
Check your measured example
One measured 144-inch row, with selected 18-inch centers and 9-inch margins at both ends. Count 8 field-production positions.
Reference and growing system: USU’s leafy-green field-production table lists collards at 12–18 inches within rows 24–30 inches apart. Preserve this mature field-production context.
| Quantity | Calculated result |
|---|---|
| Usable row length (in) | 144 |
| Selected center spacing (in) | 18 |
| Margin at each row end (in) | 9 |
| Positions in this row | 8 |
| First center from row start (in) | 9 |
| Last center from row start (in) | 135 |
| What is being counted | field-production positions |
The worked example uses a 144-inch row, 18-inch centers and 9-inch margins at both ends. The first center is at 9 inches, the last at 135 inches, and the count is 8 field-production positions. This is a geometrical placement example within USU's field-production range, not crop advice or a yield estimate.
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 source range of 12 to 18 inches within rows and 24 to 30 inches between rows is recorded.
- The chosen within-row value is labeled as a scenario and falls inside the range.
- The row length and both end margins are measured and written down.
- The count is described as field-production positions, not seeds or seedlings.
- The between-row distance and access space are chosen separately from the within-row count.
Questions that come up while planning
What spacing does the source give for collards?
USU's leafy-green field-production table lists collards at 12 to 18 inches within rows that are 24 to 30 inches apart. This is mature field-production guidance.
Why does the example use 18 inches instead of 12 inches?
The example is a labeled scenario using the wide end of the within-row range. It is a geometrical placement example, not a claim that 18 inches is best for every collard crop.
Does the 8-position count include seeds or seedlings?
No. The counted item is field-production positions, meaning the points where established plants would sit along the measured row. Sowing and thinning are separate decisions.
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.
- Planting and SpacingUtah State University Extension