What is square foot gardening?

Square foot gardening is a method developed by Mel Bartholomew that divides a raised bed into a grid of 1-foot squares. Each square holds a set number of plants based on their mature spacing — crowded crops like radishes get 16 per square, large crops like tomatoes get just 1.

How is plants per square foot calculated?

Each 12×12-inch square is divided by the plant's spacing. A plant needing 4 inches of space fits in a 3×3 sub-grid (9 plants). A plant needing 6 inches fits in a 2×2 grid (4 plants). The formula is floor(12 / spacing)² per square foot.

Does this account for border spacing?

The calculator uses the standard square-foot gardening assumption that each plant occupies the full spacing from center to edge of its cell. Half-spacing at the bed border is not deducted, which matches the Bartholomew method for raised beds with no paths inside.

Can I plan more than one plant type in the same bed?

Yes. Use the "Add Plant" button to add multiple rows. Each plant type shows its own count and color in the grid, so you can visualize a companion-planting layout.

What spacing should I use for common vegetables?

Common spacings: lettuce 6 in (4/sq ft), spinach 3 in (16/sq ft), carrots 3 in (16/sq ft), radishes 3 in (16/sq ft), beets 4 in (9/sq ft), onions 4 in (9/sq ft), bush beans 6 in (4/sq ft), peas 6 in (4/sq ft), peppers 12 in (1/sq ft), tomatoes 12–18 in (1/sq ft), squash 18–24 in (1/sq ft).

Square Foot Garden Planner

Name: Square Foot Garden Planner
Availability: InStock
Author: Nham Vu

Enter your raised bed dimensions and plant spacing to see exactly how many plants fit and get a visual grid layout.

Bed Dimensions

Length (ft)

Width (ft)

Plants

Configure your bed and plants, then click Calculate.

Summary

Enter your raised bed dimensions and plant spacing to see exactly how many plants fit and get a visual grid layout.

How it works

Enter your garden bed length and width in feet.
Select a plant from the preset list or enter a custom spacing in inches.
The planner divides each square foot into cells based on spacing — for example, 4-inch spacing fits 9 plants per sq ft.
The total plant count and a color-coded grid are shown instantly.
Add multiple plant types to plan a mixed bed and see totals per plant.

Use cases

Planning how many tomato, pepper, or lettuce plants fit a 4×8 raised bed.
Comparing planting density for different vegetable spacing requirements.
Designing a companion-planting layout with mixed crops.
Estimating seed or transplant quantities before buying.
Teaching kids or beginners the square-foot gardening method.
Replanning a bed mid-season after removing a finished crop.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu