Guide
Square foot gardening
A 4 × 4 ft bed, a grid of one-foot squares, and a fixed number of plants in each.
Square foot gardening divides a shallow raised bed into one-foot squares and plants each square at a set density: 1, 4, 9 or 16 plants depending on size. A 4 × 4 ft bed of 16 squares at 6 in deep takes about 254 litres (9.0 cu ft) of Mel’s Mix.
How it works
- Build a 4 × 4 ft bed, 6 in deep, so every square can be reached from the edge without stepping on the soil.
- Fill it with Mel’s Mix: equal parts compost, peat or coir, and vermiculite, by volume (the full recipe has substitutions). The mix never compacts, which is what lets 6 in be enough.
- Lay a grid of lath or string across the top to mark sixteen one-foot squares.
- Plant each square at its density from the table below, one crop per square, and replant a square as soon as it is harvested.
Plants per square
The number per square comes from each plant’s spacing: a plant spaced 3 in apart fits a 4 × 4 grid of 16 in one square, 6 in fits 4, and anything spaced wider than 12 in takes more than one square. These are the same spacings the plant spacing calculator uses.
| Plant | Spacing | Per square | Support |
|---|---|---|---|
| Carrot | 3 in | 16 per square | none |
| Radish | 3 in | 16 per square | none |
| Beetroot | 4 in | 9 per square | none |
| Onion (sets) | 4 in | 9 per square | none |
| Pea | 4 in | 9 per square | netted trellis |
| Spinach | 6 in | 4 per square | none |
| Garlic | 6 in | 4 per square | none |
| Bush bean | 6 in | 4 per square | none |
| Coriander / cilantro | 6 in | 4 per square | none |
| Cucumber | 12 in | 1 per square | vertical trellis |
| Lettuce (leaf) | 8 in | 1 per square | none |
| Chard | 12 in | 1 per square | none |
| Pole bean | 8 in | 1 per square | tall trellis or pole |
| Strawberry | 12 in | 1 per square | none |
| Basil | 10 in | 1 per square | none |
| Parsley | 8 in | 1 per square | none |
| Mint | 12 in | 1 per square | none |
| Thyme | 10 in | 1 per square | none |
| Tomato (indeterminate) | 24 in | 1 per 4 squares | tall trellis or cage |
| Cherry tomato | 18 in | 1 per 4 squares | tall trellis or cage |
| Pepper | 18 in | 1 per 4 squares | short stake |
| Eggplant | 24 in | 1 per 4 squares | short stake |
| Kale | 18 in | 1 per 4 squares | none |
| Rosemary | 24 in | 1 per 4 squares | none |
| Zucchini / summer squash | 36 in | 1 per 9 squares | none |
Does square foot gardening work?
For a small space, yes, and the reasons are mostly mechanical. The loose mix and the fact that nobody walks on the bed mean roots spread easily in a shallow depth, and planting by the square rather than in rows uses the space that rows leave as paths. The trade-offs are real too: Mel’s Mix is expensive per cubic foot, 6 in is too shallow for long carrots, parsnips or potatoes without a deeper square, and large plants like squash and tomatoes crowd their neighbours unless they are trained up a trellis on the north side.
Can you square foot garden in the ground?
The grid and the planting densities work anywhere the soil is loose and never walked on. In the ground that usually means digging in plenty of compost and marking permanent paths, so the growing area is never compacted. What you lose is the 6 in shortcut: ordinary ground soil needs to be worked deeper to give the same root run.