About the Square Foot Garden Planner
This square foot garden planner turns a list of crops into a planting plan for a raised bed divided into a 1 × 1 foot grid. Enter the bed size, then type one crop per line with the number of squares you want to give it — for example “Lettuce: 3”. The planner looks up how many plants of that crop fit in one square, multiplies it out and tells you the total number of plants, how many squares you have used and how many are still free.
Square-foot gardening packs plants closer than traditional rows by spacing them evenly in each square: large plants such as tomatoes, peppers and broccoli get one square each, lettuce and chard four, beets, spinach and bush beans nine, and carrots, radishes and onions sixteen. Sprawling crops like zucchini need several squares per plant, while cucumbers, melons and pole beans fit tightly when grown up a trellis.
The spacing figures follow widely used square-foot gardening charts; variety and climate matter, so a compact bush tomato and a giant indeterminate behave differently. If a crop is not in the list, or you want your own spacing, add “@ n” after the square count to set plants per square, for example “Arugula: 2 @ 16”.
With the default inputs, the total plants is 125 plants. Change any value above to recalculate instantly.
How to use the square foot garden planner
- 1Enter the bed length and width in feet.
- 2Type each crop on its own line followed by the number of squares, e.g. “Lettuce: 3”.
- 3Add “@ n” to any line to use your own plants-per-square figure.
- 4Check the free-squares figure and adjust until the plan fits the bed.
- 5Use the plan table to mark out squares and sow or transplant at the spacing shown.
Formula and method
A square-foot bed is divided into a grid of 1 × 1 ft squares, so a 4 × 4 ft bed has 16 squares and a 4 × 8 ft bed has 32. Each crop is assigned a whole number of squares, and each square holds a fixed number of plants based on the plant’s mature size: 1 (extra large), 4 (large), 9 (medium) or 16 (small). Plants are spaced evenly in a square — 4 per square means 6 inches apart, 9 means 4 inches and 16 means 3 inches.
Very large vining crops take more than one square per plant, for example one zucchini per 9 squares or one trellised melon per 2 squares; the planner rounds those down to whole plants. Crops it does not recognise are counted toward the squares used but contribute no plants until you supply your own “@ n” spacing.
- Squares
- Number of 1 × 1 ft squares assigned to a crop
- Plants per square
- 1, 4, 9 or 16 for most crops; fractional for sprawling vines
Worked examples
Classic 4 × 4 ft starter bed
Two squares each of tomato and pepper hold 1 plant each (4 plants), 3 squares of lettuce hold 12, 2 squares each of carrot and onion hold 32 each, 3 squares of bush beans hold 27 and 2 squares of spinach hold 18 — 125 plants in exactly 16 squares.
4 × 8 ft bed with vines and a custom crop
Four tomatoes, 4 trellised cucumbers (2 per square), 1 zucchini filling 9 squares, 32 pole beans, 8 basil, 48 radishes and 8 plants of the custom herb at 4 per square add up to 105 plants in 26 of the 32 squares, leaving 6 free.
Unrecognised crop without a spacing
A 3 × 3 ft bed has 9 squares. The two tomato squares give 2 plants; dragon fruit is not in the spacing chart, so its square is counted as used but adds no plants until you add “@ n”.
Frequently asked questions
How many plants per square foot?+
Standard square-foot gardening uses 1 plant per square for large crops (tomato, pepper, broccoli, cabbage), 4 for lettuce, chard and herbs, 9 for spinach, beets and bush beans, and 16 for carrots, radishes and onions.
How deep should a square foot garden bed be?+
Six inches of loose, rich mix is enough for most salad crops and herbs, while 8–12 inches suits carrots, potatoes and tomatoes better. Use the raised bed soil calculator to work out how much mix to buy.
How many tomatoes can I plant in a 4 × 4 bed?+
At one staked or caged tomato per square you could technically fit 16, but most gardeners plant 2–4 along the north side so they do not shade the rest of the bed, and fill the remaining squares with smaller crops.
How do I plant zucchini in a square foot garden?+
Zucchini and other bush summer squash spread widely, so the original method gives one plant a 3 × 3 block of 9 squares. Trellised vining squash and melons can be grown at one plant per 2 squares instead.
Why are beds limited to 4 feet wide?+
A 4-foot width lets you reach the center from either side without stepping on the soil, which keeps it loose and uncompacted. Beds against a wall or fence should be no more than about 2–3 feet deep.