What the source spacing covers
The guidance is a thinning target: dill plants are thinned to 9 inches apart within rows that are 12 inches apart. Treat 9 inches as the in-row center interval for retained plants, not as a sowing depth, seed spacing, or a rule for every crop. The 12-inch figure describes the distance between rows, so it belongs to the layout decision rather than the count along one row.
Sowing, thinning, and initial planting are different stages. You may sow more densely and then thin to the retained spacing, or set out plants at the retained spacing from the start. The count below refers to plants you keep after thinning, not seeds sown and not seedlings removed.
- Confirm whether your goal is leaf harvest or seed harvest before marking the area.
- Decide the in-row center interval you will use for retained plants, using the 9-inch figure for the labeled example.
- Decide row-to-row distance separately, using the 12-inch figure as context.
- Mark retained plant positions only after thinning decisions are made.
Source context: Utah State University Extension
Worked example: one 96-inch row
This is a geometrical example, not crop advice for every garden. Take one measured row 96 inches long, choose 9-inch centers for retained plants, and allow a 4.5-inch margin at both ends. The first retained plant center falls at 4.5 inches and the last at 85.5 inches. Counting those positions gives 10 retained plants.
The counted item is retained plants, not seeds, seedlings, or harvested stems. The 4.5-inch end margins are part of this example only; they are not a dill spacing rule. If you change the row length, center interval, or either end margin, the count changes. The linked row calculator can count this exact length, center interval, and both end margins in inches or centimeters.
- Measure the row length in inches or centimeters.
- Enter the selected center interval for retained plants.
- Enter both end margins, checking that they match your marking plan.
- Read the result as the number of retained plant positions, then verify the first and last centers on the ground.
Source context: Utah State University Extension
From one row to the whole growing area
One row is not an entire garden layout. The 96-inch example answers only how many retained plants fit along that measured line under the chosen interval and margins. It does not set the number of rows, the distance between adjacent rows, or the space needed for access.
Choose those separately. The source gives 12 inches between rows, but access paths, supports if you use them, adjacent-row clearance, and the mature habit of your dill still need their own decisions. Do not copy the 9-inch in-row interval into a between-row distance, and do not treat a generic square grid as a dill spacing recommendation. For dill, keep the row and plant count tied to the figures and your own measured layout.
- Sketch each row as a separate line rather than assuming one row represents the garden.
- Set row-to-row distance using the 12-inch context and your access needs.
- Check adjacent rows and any supports before finalizing the layout.
- Record the retained plant count per row and add rows only after the layout is checked.
Source context: Utah State University Extension
Check your measured example
One measured 96-inch row, with selected 9-inch centers and 4.5-inch margins at both ends. Count 10 retained plants.
Reference and growing system: USU gives dill plants thinned to 9 inches apart within rows 12 inches apart. Choose the leaf or seed harvest goal before laying out the growing area.
| Quantity | Calculated result |
|---|---|
| Usable row length (in) | 96 |
| Selected center spacing (in) | 9 |
| Margin at each row end (in) | 4.5 |
| Positions in this row | 10 |
| First center from row start (in) | 4.5 |
| Last center from row start (in) | 85.5 |
| What is being counted | retained plants |
The example is a geometrical count for one 96-inch row. With 9-inch centers and 4.5-inch margins at both ends, the first center is at 4.5 inches, the last at 85.5 inches, and 10 retained plants are counted. The margins are example choices, not dill advice, and the result does not describe an entire garden layout.
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
- State whether the goal is leaf harvest or seed harvest.
- Label the 9-inch interval as in-row spacing for retained plants.
- Keep the 12-inch figure as row-to-row context, not an in-row count.
- Confirm the example uses a 96-inch row, 9-inch centers, and 4.5-inch end margins.
- Verify the count is 10 retained plants and that one row is not the whole layout.
Questions that come up while planning
How far apart should dill plants be?
USU gives dill plants thinned to 9 inches apart within rows 12 inches apart. The 9-inch figure is the in-row spacing for retained plants; the 12-inch figure is row-to-row context.
Does the 96-inch example count seeds or plants?
It counts retained plants. With 9-inch centers and 4.5-inch margins at both ends, the first center is at 4.5 inches, the last at 85.5 inches, and the count is 10.
Can I use one row count as my whole garden plan?
No. One row count covers only that measured row. Row-to-row distance, access, supports, adjacent rows, and mature habit 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 Dill in Your GardenUtah State University Extension