How Spacing Numbers Are Set
The spacing figures behind this tool come from university extension publications and seed-supplier charts — the same verified sources every Gardenable crop entry is built on. For each crop we store a single in-row spacing, a between-row spacing, and a plants-per-square-foot density, then reuse those values consistently across every tool in the hub so a tomato is spaced the same way whether you're planning a bed or counting plants.
High-density crops — radishes, carrots, leaf lettuce, spinach — are an exception to traditional row spacing. These are typically broadcast or band-sown and counted by square-foot gardening conventions instead, so the tool reports a per-square count rather than a misleading "rows × plants" figure. Where a crop has no documented row spacing, the tool falls back to a plain area-based count.
When To Tighten or Widen
Treat the suggested spacing as a starting point. In a raised bed with rich, well-drained soil and reliable irrigation you can push plants closer together for a higher yield per square foot; in dry climates or compacted in-ground soil, give them more room so each plant has the water and root space to size up. The right answer is a compromise between total yield and individual plant size — closer spacing trades bigger individual plants for more of them.
Frequently Asked Questions
How is plant spacing calculated?
Every crop has a documented in-row spacing, a between-row spacing, and a plants-per-square-foot density, drawn from the Gardenable growing database. This tool multiplies the area you enter by that density to get a total plant count, then — for rectangular beds — divides your bed's width and length by the spacing to suggest a row layout. The underlying numbers come from university extension publications and seed-supplier charts, so you don't have to look them up per crop.
What's the difference between this and the Square-Foot Garden Planner?
This is a single-crop quick lookup: pick one crop, enter an area, and see how many plants fit. The Square-Foot Garden Planner is a multi-crop layout tool — it packs several crops into a visual grid, separates antagonists, and back-fills empty squares. Use this calculator when you just want a count for one crop; use the planner when you're designing a whole bed.
Why does my crop suggest different spacing than other sources?
Recommended spacing genuinely varies between extension publications, seed catalogs, and growing methods — intensive raised-bed spacing is tighter than traditional row spacing, and individual cultivars differ. Gardenable uses a single consolidated reference value per crop for consistency across tools. For a specific variety, the seed packet is always the most authoritative source; treat our number as a sensible default.