Plant Spacing Chart: In-Row Inches + Square-Foot Counts

What a spacing chart tells you, and why it matters

A spacing chart tells you how much room each plant needs when it is full grown. Seedlings look tiny, so it is easy to plant them too close.

Crowding costs you in two ways. Plants fight for water, light, and food, so each one grows less. And tight plants stay damp longer.

Alabama Extension explains why that matters. Good spacing lets air move, so leaves dry faster. Crowded plants pass disease from leaf to leaf by touch and by splashing water.

Too wide wastes bed space instead. The chart below is the middle ground: room to grow, with no soil left idle.

How to read the chart

Each crop gets three numbers, plus two ranges from Kansas State University for comparison.

• In-row spacing is how far apart to set plants down one row. It is the calculator's default.
• Between rows is the gap from one row to the next. It is wider, so you can walk and reach.
• Per square foot is the count for one 12-inch square in square-foot gardening.
• K-State rows is the in-row and between-row range from the K-State Vegetable Garden Planting Guide, for gardens planted in rows.
• K-State beds is the tighter spacing from K-State's Intensive Spacing for Raised Beds, where plants sit on an even grid with no paths.

Use the tight end of a range in rich, well-watered soil. Use the wide end for big varieties or poor soil.

Large and vining crops

Leafy, root, and small crops

The in-row numbers are the calculator's defaults. Most sit inside at least one K-State range. A few run a little roomier than K-State: basil, onions, and beets. Treat those as a comfortable starting point, not a rule, and nudge them in the calculator if you want a tighter bed.

Row spacing is where sources differ most. K-State's row guide leaves room for walking paths and garden tools, so its gaps run wider. In a raised bed you don't walk in, rows can close up toward the in-row number.

How the two formats relate

The in-row inch and the per-square count describe nearly the same density two ways. A per-square count is a small grid inside one 12-inch square, so its spacing is set by the tier, not the crop. Garlic, for example, sits 6 inches apart in a row but about 4 inches apart at 9 per square.

Square-foot tiers at a glance

• 1 per square = 12 in apart: tomato, pepper, eggplant, broccoli, cabbage, cauliflower
• 4 per square = 6 in apart: lettuce, basil, Swiss chard
• 9 per square = 4 in apart: bush beans, spinach, beets, onions, garlic
• 16 per square = 3 in apart: carrots, radishes

K-State's own square-foot sheet matches most of this. It puts broccoli, cabbage, cauliflower, eggplant, and pepper at a whole square each, chard and leaf lettuce at 6 inches, and bush beans and spinach at 4 inches. One difference: K-State puts beets and onions in the 3-inch tier (16 per square). The calculator uses 9, which gives each root more room.

How many plants fit your bed

The chart gives spacing. The count depends on your bed size and the layout you pick.

The table below uses the calculator's math for three common 4-foot-wide beds. "Offset" means triangular spacing, where every other row shifts over by half a space.

The calculator keeps half a space between each plant and the frame. That is why a 48-inch-wide bed fits two tomato rows at 24 inches, not three.

Look at the square-foot column for big crops. It says 32 tomatoes fit a 4x8 bed, but the 24-inch chart says 8. Full-size tomatoes need more than one square each. The per-square count is a starting point for compact plants, not a law.

When offset spacing pays off

Offset rows sit closer together than square rows. The gap between them is about 0.866 times the spacing. On paper, that fits about 15 percent more plants.

In a real bed, the edges eat some of that. Offset rows lose a plant at the ends of every other row. In a 4-foot-wide bed, the math only wins when the crop is small enough to gain an extra row.

• Small crops gain: carrots and peas go from 512 to 567 in a 4x8 bed. That is about 11 percent more.
• Mid-size crops break even or lose: lettuce drops from 72 to 69.
• Big crops lose: tomatoes drop from 8 to 7, and peppers from 10 to 9.

So use offset spacing for roots, onions, garlic, and greens sown thick. Use a square grid for big transplants. The Plant Spacing Calculator shows both counts for your exact bed.

Planting in rows instead of beds

Row gardens need a different number: how many plants per length of row. The table below compares the calculator's in-row spacing with K-State's "plants per 10-foot row."

The calculator counts a 10-foot row as 120 inches divided by the spacing, rounded down. K-State's counts come from its own spacing ranges, so they can run higher for crops it spaces tighter, like carrots.

How many plants to grow per person

Spacing tells you how many plants fit. It doesn't tell you how many you need. For that, K-State's planting guide gives a typical harvest per 10 feet of row and a suggested planting per person.

Use it to size the garden before you size the bed. The yields are averages, so treat them as a starting point.

Source: K-State Vegetable Garden Planting Guide. A "hill" is one planting spot, often a low mound with a few plants on it.

Here is how the two tables work together. A family of four wants 12 to 20 tomato plants (3 to 5 each). At 24 inches, a 4x8 bed holds 8. So plan on two to three 4x8 beds for tomatoes alone.

Potatoes show the other side. At 50 to 100 feet of row per person, they need far more ground than a few beds can give. If space is tight, grow a short row for early "new" potatoes and give the rest of the bed to crops that yield more per foot.

Greens and roots are the space savers. Ten feet of leaf lettuce, or 5 to 10 feet of carrots or beets, covers one person. At chart spacing, that fits in a single 4x4 bed with room left over.

How to use a square-foot grid

Square-foot gardening swaps row math for a physical grid. You lay 12-inch squares over the bed and treat each square as its own small plot.

1. Mark a grid of 12-inch squares across the bed with string or thin boards.
2. Give each square a single crop.
3. Plant the per-square count from the chart: 1 tomato, 4 lettuce, 9 beans, 16 carrots.
4. Space the plants evenly inside the square so they share the foot of soil.

The grid does the spacing for you. You never measure an inch down a row again.

Keep the bed narrow enough to reach. SDSU Extension suggests 4 feet wide or less if you can reach from both sides, and 3 feet or less if you can reach from only one.

Spacing in a raised bed

The bed sets the limits for spacing. A deeper bed lets roots run, so root crops can reach full size at chart spacing. A wider bed gives offset rows room to gain an extra row.

Still building or topping up? Fill the bed first. The raised bed soil guide covers the mix and bag counts, and how much soil for a raised bed walks the volume math.

For one crop in depth, see how far apart to plant tomatoes, carrots, or lettuce.

Put your bed's numbers in

In-row inches and per-square counts are the same density measured two ways. Offset rows help small crops and cost big ones a plant. The chart gives the spacing, but only your bed size gives the count.

Pick your crop and bed size in the Plant Spacing Calculator to see how many plants fit in square, triangular, and square-foot layouts, with a grid preview for your exact bed.