Square foot gardening trades rows for a grid, and the arithmetic changes with it. Rather than working out how many feet of row a crop needs, you decide how many one-foot squares to give it, and the crop's density tells you how many plants that is.
This planner does that bookkeeping. Set a grid size, pick a crop, tap squares to plant them, and the totals build underneath.
How to use it
- Set the rows and columns. A four by four grid is the classic starting bed. Four by eight matches a standard timber-framed raised bed.
- Choose a crop to place. The dropdown shows each crop's density — how many go in a square, or how many squares one plant needs.
- Tap squares to plant them. Tapping a square that already holds the selected crop clears it again.
- Print the plan with the button at the bottom. Grid lines and labels print legibly; the site furniture does not.
The plan is saved in your browser as you work, and also written into the page address, so you can send the link to yourself to open on another device.
How it is calculated
There is no clever geometry here — it is bookkeeping, applied carefully:
plants = squares assigned x plants per square foot
The care is in what happens when that number is less than one. Crops such as zucchini, winter squash and pumpkin have a density below 1, meaning they need several squares per plant rather than several plants per square:
squares per plant = ceil(1 / plants per square foot)
For those crops the planner rounds down, and says so. Assign a zucchini one square and it reports zero plants with a note explaining it needs about ten. Assign it ten and it reports one. That is more useful than a cheerful "0.1 plants".
A worked example
A four by four grid, sixteen squares. Two squares of carrots, one of lettuce, one of tomato:
- Carrots: 2 squares x 16 per square = 32 plants
- Lettuce: 1 square x 4 = 4 plants
- Tomato: 1 square x 1 = 1 plant
- Total: 37 plants in four squares, with twelve squares still free
Replace the tomato square with zucchini and the planner will tell you that one square is not enough: at 0.11 plants per square, a zucchini wants around ten.
Plants per square foot
| Crop | Per square, square foot gardening method |
|---|---|
| Radish | 16 per square |
| Beet | 9 per square |
| Carrot | 9 per square |
| Garlic | 9 per square |
| Onion | 9 per square |
| Pea | 9 per square |
| Spinach | 9 per square |
| Bush bean | 4 per square |
| Lettuce | 4 per square |
| Swiss chard | 4 per square |
| Cucumber | 2 per square |
| Broccoli | 1 per square |
| Cabbage | 1 per square |
| Cauliflower | 1 per square |
| Pepper | 1 per square |
| Potato | 1 per square |
| Sweet potato | 1 per square |
| Eggplant | 1 per 2 squares |
| Tomato | 1 per 2 squares |
| Zucchini | 1 per 2 squares |
| Asparagus | No square foot gardening figure confirmed for this crop |
| Basil | No square foot gardening figure confirmed for this crop |
| Blueberry | No square foot gardening figure confirmed for this crop |
| Cilantro | No square foot gardening figure confirmed for this crop |
| Dill | No square foot gardening figure confirmed for this crop |
| Kale | No square foot gardening figure confirmed for this crop |
| Lavender | No square foot gardening figure confirmed for this crop |
| Marigold | No square foot gardening figure confirmed for this crop |
| Okra | No square foot gardening figure confirmed for this crop |
| Oregano | No square foot gardening figure confirmed for this crop |
| Parsley | No square foot gardening figure confirmed for this crop |
| Pumpkin | No square foot gardening figure confirmed for this crop |
| Rosemary | No square foot gardening figure confirmed for this crop |
| Sage | No square foot gardening figure confirmed for this crop |
| Strawberry | No square foot gardening figure confirmed for this crop |
| Sweet corn | No square foot gardening figure confirmed for this crop |
| Thyme | No square foot gardening figure confirmed for this crop |
| Watermelon | No square foot gardening figure confirmed for this crop |
| Winter squash | No square foot gardening figure confirmed for this crop |
Square foot gardening figures come from Mel Bartholomew’s method and assume an intensive bed of amended soil. Spacing-derived figures assume conventional rows.
Densities that come out as "1 per N squares" are the reciprocal of the published plants-per-square-foot figure, rounded up to whole squares. Where a crop has no figure, the Cornell CALS page does not name it — the planner falls back to its in-row spacing and says so, rather than inventing a square count.
Tips and common mistakes
Put the sprawlers on the edge. A zucchini or a squash given its ten squares will still spill over the frame. Planting it at the edge of the bed, facing out, saves the plants next to it.
Trellis the climbers. Cucumbers, pole beans and peas cost almost no floor space when they go up rather than out, which is what makes them good value in a small grid.
Do not plan every square for the whole season at once. Fast crops come and go two or three times while a tomato occupies its square from May to October. Plan the early round, then replan as squares empty.
Watch the shade. In the northern hemisphere, anything tall belongs on the north side of the bed, or it will put the shorter crops in shadow from midsummer onwards.
Check the depth your crops want. A grid says nothing about depth, and carrots in a six inch bed will fork and stunt. Deep-rooted crops want twelve inches of loose soil.