🌱 Square Foot Gardening Plants Per Box Calculator
Using the square-foot-gardening method, enter your raised bed's dimensions (in whole feet) and a crop to see how many plants fit.
Squares first, then plants per square
The bed is measured in whole square feet, and each square is filled at a density fixed by the crop:
squares = bed length × bed width
plants = squares × plants per squareA 4 ft by 4 ft bed is 16 squares, so the default tomato setting gives 16 plants. The four densities are the classic square-foot spacings, each one a grid drawn inside a single 12 in square:
| Crop group | Per square | Grid | Spacing |
|---|---|---|---|
| Tomato, pepper | 1 | 1 × 1 | 12 in |
| Lettuce, Swiss chard | 4 | 2 × 2 | 6 in |
| Bush beans, beets | 9 | 3 × 3 | 4 in |
| Carrots, radishes | 16 | 4 × 4 | 3 in |
Laying it out
- Four feet is the standard width for a reason. Two feet is about as far as most people can reach comfortably, so a 4 ft bed can be worked from both sides without treading on the soil.
- One tomato per square assumes it goes up. That density is for a staked or caged plant; left to sprawl, an indeterminate variety will cover four squares or more.
- Partial squares are not rounded down. Type 3.5 by 3 and the tool returns 10.5 squares and the plant count that follows, so round the figure down yourself for an odd-sized bed.
Frequently asked questions
How many plants fit in a 4x4 square foot garden?
Sixteen squares' worth: 16 tomatoes or peppers, 64 lettuces, 144 bush beans or beets, or 256 carrots or radishes.
How far apart do you space 16 carrots in one square foot?
Three inches. Sixteen plants sit on a 4 by 4 grid inside the 12 in square, so every seed is 3 in from its neighbours in both directions.
Can you plant one tomato per square foot?
That is what this calculator assumes, and it works when the plant is staked, caged or trellised so it grows upward. A sprawling plant needs the room of several squares.