Square Foot Gardening: Spacing Chart, Calculator & Planner

Grow more food in less space. 32 crops. One grid. Zero wasted squares.

Square foot gardening is a raised bed method that divides your growing area into 1-foot squares, each planted with a precise number of crops based on their size. It eliminates the wasted space of traditional row gardening, reduces weeding, and makes garden planning intuitive enough for a complete beginner.

This guide covers the method, a spacing chart for 32 common crops, the soil recipe, how to plan your SFG layout with companion planting, zone-based timing, succession planting, and the most common mistakes that reduce SFG yields.

All spacing data comes from the Plant Anywhere crop database of 437 plants. The planner includes a built-in square foot grid that automates plant counts and spacing per square.

What Is Square Foot Gardening?

Square foot gardening was developed by Mel Bartholomew, a retired civil engineer, in 1981. He looked at traditional row gardening -- with its wide paths, wasted space, and excessive thinning -- and asked a straightforward engineering question: what is the most food you can grow in the smallest possible area?

His answer was a raised bed divided into a grid of 1-foot squares. Instead of scattering seeds across a row and then thinning, you plant the exact number of seeds or seedlings each square can support. A square that holds one tomato plant does not get two. A square that holds sixteen radishes does not get twenty.

The method has three core principles:

1. Small beds, not rows. A 4-by-4-foot or 4-by-8-foot raised bed replaces traditional rows. You never step in the bed, so the soil stays loose and uncompacted.
2. Grid layout. The bed is divided into 1-foot squares using physical dividers (string, wood strips, or lattice). Each square is an independent planting unit.
3. Intensive spacing. Each square gets the maximum number of plants it can support based on the crop's mature size. No wasted space between rows. No thinning.

The result: a 4-by-4-foot SFG bed produces roughly the same harvest as a 12-by-12-foot traditional row garden, in one-ninth the space, with a fraction of the weeding. The method is especially effective for urban gardeners, renters, and anyone with limited yard space.

Square Foot Gardening Spacing Chart

This is the reference table for how many plants fit in each square foot. The standard SFG spacing categories are 1, 2, 4, 8, 9, or 16 plants per square. The category is determined by the crop's mature canopy diameter and root spread.

This chart covers the 32 most commonly grown SFG crops. The Plant Anywhere planner includes spacing data for all 437 crops in its database and automatically calculates plant counts when you use the square foot grid layout.

How to read the spacing categories

The per-square-foot number follows a simple pattern based on plant size:

• 16 per square: Very small plants (3-inch spacing). Radishes, carrots, green onions, chives. You are planting in a 4x4 mini-grid within each square.
• 9 per square: Small plants (4-inch spacing). Beets, onions, garlic, spinach, bush beans. A 3x3 mini-grid.
• 8 per square: Small-medium plants. Peas. A 2x4 arrangement.
• 4 per square: Medium plants (6-inch spacing). Lettuce, basil, herbs, Swiss chard, corn. A 2x2 mini-grid.
• 2 per square: Large-medium plants (8-inch spacing). Cucumbers (trellised). One on each side of the square.
• 1 per square: Large plants (12-inch spacing). Tomatoes, peppers, brassicas, zucchini, eggplant, kale. The entire square is dedicated to one plant.

How to Build a Square Foot Garden Bed

Bed dimensions

The standard SFG bed is 4 feet wide. This is not arbitrary -- 4 feet is the maximum width that allows an adult to reach the center from either side without stepping into the bed. Stepping in the bed compacts the soil, which defeats the purpose of a raised bed.

Length is flexible. The most common sizes:

• 4 x 4 feet (16 squares): Ideal for beginners. Enough room for 8 to 10 different crops. One person can manage it easily.
• 4 x 8 feet (32 squares): The most popular size. Provides enough variety for a full vegetable garden and space for companion planting groups.
• 4 x 12 feet (48 squares): For serious gardeners with space. Consider splitting into two 4x6 beds with a path between them for easier access.

Depth should be at least 6 inches. For root vegetables (carrots, beets, turnips) and large fruiting crops (tomatoes), 10 to 12 inches is better. If your bed sits on concrete, a driveway, or very heavy clay, go with 12 inches.

Materials

Use untreated cedar, redwood, or Douglas fir. These woods resist rot without chemical treatment. Avoid pressure-treated lumber near food crops -- while modern ACQ treatment is considered safe by the EPA, many gardeners prefer to avoid it. Pine is the cheapest option but may need replacing after 3 to 5 seasons.

No bottom is needed. The open bottom allows drainage and lets earthworms enter from below. If you are building on grass, lay cardboard under the bed to suppress weeds -- it will decompose within one season.

The grid

The grid is what makes square foot gardening work. Without it, you lose the discipline of planting the right number of plants per square and the visual structure that makes the method intuitive.

Options for making the grid:

• Wood lath or thin strips screwed or nailed across the bed frame
• String tied between small nails on the inner edges of the frame
• Vinyl mini-blinds cut to length (durable, weather-resistant, free if you have old blinds)
• A pre-made lattice panel cut to fit

The Soil Mix: Mel's Mix

The original SFG soil recipe, called Mel's Mix, is one of the reasons the method works so well. It solves the three most common soil problems in one step: poor drainage, low nutrients, and compaction.

Mel's Mix recipe:

• 1/3 blended compost: Mix compost from at least two sources (homemade, mushroom compost, municipal compost, worm castings). The blend provides a wider range of nutrients and microbial life than a single source.
• 1/3 peat moss or coconut coir: Holds moisture and keeps the mix lightweight. Coconut coir is the more sustainable option (peat bogs regenerate slowly). Either works.
• 1/3 coarse vermiculite: Aerates the soil, improves drainage, and retains moisture at the root level. Use coarse grade, not fine -- fine vermiculite compacts.

For a 4 x 4 x 1-foot bed, you need approximately 16 cubic feet of Mel's Mix (roughly 5.3 cubic feet of each ingredient). For a 4 x 8 x 1-foot bed, double that.

Mel's Mix does not need fertilizer in the first season. In subsequent years, add 1 to 2 inches of fresh compost on top of each square before planting. The Plant Anywhere compost tracker helps you maintain the right C:N ratio for fast, effective composting to replenish your SFG beds.

Planning Your SFG Layout

The grid makes SFG planning visual and concrete. Each square is a decision: what crop, how many plants, and where relative to its neighbors. Here is how to plan a productive layout.

Height placement

Place tall crops on the north side (or north edge) of the bed so they do not shade shorter crops. In a 4x8 bed:

• North row: Trellised crops (peas, cucumbers, pole beans) or tall crops (corn, tomatoes with cages)
• Middle rows: Medium crops (peppers, basil, lettuce, chard)
• South row: Low crops (radishes, carrots, beets, onions, herbs)

Companion planting in SFG

Because SFG squares are adjacent, companion planting matters more than in a traditional row garden where crops are spread farther apart. Adjacent squares are within 1 to 2 feet of each other -- well within the effective range for pest deterrence and nitrogen fixation.

Good SFG square pairings:

• Tomato square next to basil square (pest deterrence)
• Bean square next to corn square (nitrogen fixation + natural trellis)
• Carrot square next to onion square (mutual fly protection)
• Lettuce square next to tomato square (shade benefit in summer)
• Cabbage square next to dill square (parasitic wasp attraction)

SFG squares to keep apart:

• Bean squares and onion/garlic squares (allium-legume antagonism)
• Tomato squares and cabbage/broccoli squares (compete for nutrients, attract overlapping pests)
• Dill squares and carrot squares (cross-pollination risk in the same family)

The Plant Anywhere companion planting guide covers all 248 relationships with the science behind each one. In the garden planner, companion and antagonist lines draw automatically between squares as you place crops, including lines across multiple beds.

Succession planting

SFG's greatest advantage over traditional row gardening is how easily it supports succession planting. When a fast crop finishes in a square, you immediately replant that square with something new.

Example succession sequence for one square:

1. March: Plant 16 radishes (harvest in 30 days)
2. April: Radishes done. Replant with 4 lettuce (harvest in 45 days)
3. June: Lettuce done. Plant 9 bush beans (harvest in 55 days)
4. August: Beans done. Plant 9 beets for fall harvest

One square, four harvests, one season. Multiply that across 16 or 32 squares, and the total yield from an SFG bed far exceeds what a traditional row garden produces in the same footprint. The Plant Anywhere succession planting timeline (Gardener tier) shows a scrubber view of your harvest gaps so you can identify which squares should be replanted and when.

SFG Planting Schedule by Zone

Every square in your SFG bed has a planting window determined by your zone's frost dates. Cool-season squares can be planted 2 to 4 weeks before your last frost. Warm-season squares must wait until after the last frost.

Here is a simplified schedule for the most popular SFG zones:

These are approximate windows. For exact planting dates tailored to your ZIP code, use the Plant Anywhere frost date finder. It computes seed-starting, transplanting, and harvest dates for every crop in every zone based on 30-year NOAA climate averages.

Common Square Foot Gardening Mistakes

SFG is forgiving, but these five mistakes consistently reduce yields:

1. Overcrowding

The spacing chart exists for a reason. Planting 2 tomatoes in a 1-plant square or 20 carrots in a 16-carrot square reduces airflow, increases disease pressure, and lowers yield per plant. More plants does not equal more food. Stick to the chart.

2. Ignoring companion relationships

In SFG, your crops are 1 to 2 feet apart. Antagonist pairs that might coexist in a traditional garden (6 feet apart) can actively suppress each other in adjacent SFG squares. Check companions before assigning squares.

3. Not succession planting

An empty square after harvest is wasted growing season. Every square that finishes should be replanted within a week. Have your next crop's seeds or seedlings ready before the current crop comes out.

4. Skipping the grid

Without physical grid dividers, squares merge into a general planting area and you lose the precision that makes SFG work. Lay the grid before you plant. Keep it in place all season.

5. Wrong bed depth for the crop

Six inches of soil is fine for lettuce, radishes, and herbs. But tomatoes, carrots, beets, and potatoes need 10 to 12 inches. If your bed is only 6 inches deep, either avoid deep-rooted crops or build a deeper bed.

Sample SFG Layouts

Beginner 4x4 Layout (16 squares)

This layout is designed for a first-time gardener. It includes a mix of fast and slow crops, companions are grouped together, and tall crops are on the north side.

Why this layout works: Tomato and basil are companions (adjacent). Carrot and onion are companions (adjacent, mutual fly protection). Beans are away from onions (separated by carrots). Peas are trellised on the north edge. Radishes are on the south edge for easy access and fast harvest. One zucchini is enough -- it will produce heavily all summer.

Total plants: 1 tomato + 1 pepper + 1 zucchini + 12 basil + 12 lettuce + 16 peas + 16 carrots + 9 onions + 18 bush beans + 9 beets + 9 spinach + 16 radishes + 16 chives = 136 plants in 16 square feet.

Plan Your Square Foot Garden with Plant Anywhere

Plant Anywhere is a free garden planner with a built-in square foot gardening grid. When you set a bed to SFG mode, the planner divides it into 1-foot squares, shows how many plants fit in each square based on the crop you place, and draws companion and antagonist lines between adjacent squares.

What the SFG planner does:

• Automatic plant counts: Drop a crop into a square and the planner shows 1, 4, 9, or 16 plants based on the crop's spacing data from our 437-crop database.
• Companion lines: Green lines connect compatible squares. Red lines warn about antagonist pairs. Lines draw across beds, not just within them.
• Zone-aware planting calendar: Each crop in each square gets a computed planting date based on your ZIP code's frost data. The 12-month timeline shows when every square should be planted and when it will be ready to harvest.
• Succession planting timeline: The timeline scrubber (Gardener tier) shows gaps between harvests so you can identify which squares to replant and when.
• Crop rotation tracking: The planner remembers what was in each square last season and warns if you are repeating the same plant family (which increases disease pressure).
• 216 crop profiles: Every crop includes spacing, sun, frost tolerance, companion data, and growing tips.
• Free to start: The free tier includes the SFG grid, companion planting lines, planting calendar, and up to 50 plantings.

Start planning your square foot garden -- free

Related Guides

• How to Start a Vegetable Garden: A Complete Beginner's Guide
• The Complete Companion Planting Guide 2026
• Seed Starting Schedule 2026: When to Start Seeds Indoors by Zone
• Raised Bed Garden Planner: Design Your Perfect Layout
• Compost Calculator: Get Your C:N Ratio Right
• Browse All 437 Crop Profiles
• Find Your Frost Dates by ZIP Code

Frequently Asked Questions

What is square foot gardening?

Square foot gardening is a raised bed method that divides a growing area into 1-foot squares, each planted with a specific number of crops based on their spacing needs. It was developed by Mel Bartholomew in 1981 as a way to grow more food in less space with less waste.

How many plants per square foot?

The number depends on the crop's mature size. Large crops like tomatoes, peppers, and broccoli get 1 per square. Medium crops like lettuce, basil, and Swiss chard get 4. Small crops like beets, onions, and spinach get 9. Very small crops like radishes, carrots, and chives get 16.

What size should a square foot garden be?

A 4-by-4-foot bed (16 squares) is the standard beginner size. A 4-by-8-foot bed (32 squares) provides more variety. Never make a bed wider than 4 feet, or you will not be able to reach the middle without compacting the soil.

What soil do you use for square foot gardening?

The original Mel's Mix is one-third compost (blended from several sources), one-third peat moss or coconut coir, and one-third coarse vermiculite. This mix drains well, holds moisture evenly, and provides enough nutrients for most vegetables without additional fertilizer in the first season.

How deep should a square foot garden be?

Most vegetables grow well in 6 inches of soil. For deep-rooted crops like tomatoes, carrots, and potatoes, 12 inches is better. If your bed sits on hard clay or concrete, go with 12 inches to give roots enough room.

Can you do companion planting in a square foot garden?

Yes, and you should. In a square foot garden, crops are close together, making companion relationships even more important. Place companion squares next to each other (tomato next to basil) and keep antagonist pairs separated by at least one square.

How much food can a 4x4 square foot garden produce?

A well-planned 4-by-4 square foot garden can produce a continuous harvest of salad greens, herbs, and several fruiting crops throughout the season. With succession planting, a single 16-square bed provides a meaningful portion of a household's fresh vegetables from spring through fall.

Is there a free square foot garden planner?

Yes. Plant Anywhere is a free garden planner with a built-in square foot gardening grid. It shows how many plants fit in each square, draws companion and antagonist lines between adjacent squares, and computes zone-specific planting dates. The free tier supports up to 50 plantings.