Square Foot Gardening Spacing Chart

The Square Foot Method

Square foot gardening was developed by Mel Bartholomew in 1981 as a simpler, more productive alternative to traditional row gardening. The core idea: divide a raised bed into a grid of 1-foot squares using twine or lath strips, then plant a precise number of crops in each square based on their mature size.

The method works because it eliminates wasted walking-row space, concentrates soil amendments where roots actually grow, and makes succession planting intuitive. When one square is harvested, you immediately replant it with the next crop.

Setting up your grid: Use twine, wooden lath, or even venetian blind slats to divide each 4×4 or 4×8 bed into 12-inch squares. The physical grid is key: it prevents the natural tendency to overcrowd and gives you a visual map of your garden plan.

How to Determine Spacing

The rule is straightforward: take the “thin to” or “space plants” distance from the seed packet, divide 12 inches by that number to get plants per row within the square, then square the result.

• 12" spacing → 12÷12 = 1 per row → 1×1 = 1 plant per square
• 6" spacing → 12÷6 = 2 per row → 2×2 = 4 plants per square
• 4" spacing → 12÷4 = 3 per row → 3×3 = 9 plants per square
• 3" spacing → 12÷3 = 4 per row → 4×4 = 16 plants per square

For extra-large plants like squash or melons that need 18–24 inches, you allocate 2 or even 4 squares per plant.

Maximizing Your Harvest

The density chart below tells you how many to plant. Experienced SFG gardeners squeeze even more production from the same footprint with these techniques:

• Succession planting: As soon as a square is harvested, compost it lightly and replant immediately. Fast crops like radishes (25 days) and lettuce (30 days) can cycle 3–4 times per season.
• Interplanting: Pair tall crops with shade-tolerant ones. A tomato square can have lettuce or spinach at its base early in the season before the canopy fills in.
• Vertical growing: Add a trellis along the back of your bed for climbers like cucumbers, pole beans, and peas. These grow up instead of out, using just one square of ground space each.
• Thin early: For 9- and 16-per-square crops (carrots, radishes, beets), thin seedlings to proper spacing as soon as they’re 1–2" tall. Overcrowded seedlings compete for light and produce stunted roots. Water densely planted squares more frequently, since they dry out faster than single-plant squares.

Putting It All Together

Use the spacing chart below to plan your bed square by square. A few layout principles to keep in mind:

• North-side rule: Place your tallest crops (tomatoes, trellised cukes, corn) along the north edge so they don’t cast shadows over shorter plants.
• Graduate heights: Medium crops in the middle rows, shortest in front (south side).
• Companion awareness: Keep basil near tomatoes, plant dill and other umbellifers to attract beneficial insects, and separate onion-family crops from beans and peas.
• Access: Make sure you can reach every square from the bed’s edge. The standard 4-foot width means you never step on the soil.