Square vs Triangular Plant Spacing: How Many More Plants Fit

A plant tag says “space 12 inches apart”. It does not say in what pattern. There are two ways to fill a bed at a given spacing, and they give different plant counts, a different look, and a different speed of cover.

The two patterns

Square grid. Plants sit at the corners of squares. Rows and columns line up in both directions. Each plant has four near neighbors at the stated spacing, and four more on the diagonals that are farther away, at 1.4 times the spacing.

Triangular grid. Every second row is shifted sideways by half a space, and the rows are moved closer together. Each plant now has six near neighbors, all at exactly the stated spacing. This is also called staggered, offset or hexagonal planting.

Where the 15% comes from

In a triangular grid, three neighboring plants form a triangle with all three sides equal to the spacing. The distance between rows is the height of that triangle.

The 0.866 is the square root of 3, divided by 2. You do not need to remember why. What matters is the result: rows are about 87% as far apart as in a square grid, while plants within each row stay at the full spacing.

Closer rows mean more rows in the same bed:

So a triangular grid holds 15.5% more plants than a square grid at the same spacing. No plant is any closer to its neighbors than before. The pattern simply wastes less ground. In a square grid, the middle of each square is farther from any plant than it needs to be. The triangular grid closes those gaps.

Plant density at common spacings

The formulas behind the table, with the spacing in inches:

In metric, with the spacing in centimeters, replace 144 with 10,000 to get plants per square meter. At 30 cm spacing that is 11.1 plants per square meter on a square grid and 12.8 on a triangular one.

Which pattern to use

Use a triangular grid for:

• Groundcovers and mass plantings. The whole aim is to cover the soil evenly and quickly. Staggered plants close over with no bare diamonds left between them.
• Slopes. Staggered rows leave no straight channel for water to run down, so they hold soil better.
• Informal, natural-looking beds. A triangular layout does not read as rows from any angle.
• Bulbs and bedding in blocks. A fuller display from the same spacing.

Use a square grid for:

• Vegetable beds you hoe or harvest in rows. Straight lanes in both directions make it easy to get a hoe or a hand between plants.
• Formal designs. Where lines are meant to be seen.
• Square foot gardening. The method is built on a one-foot grid.
• Anything you underplant or weed by machine.

For shrubs and specimen plants set several feet apart, the pattern matters less. Place them by eye for a natural grouping, and use the calculation only to check the count.

Setting out a triangular grid

It sounds fiddly and takes ten minutes with two sticks.

1. Cut two sticks. One the length of your plant spacing, and one the length of the row distance, which is the spacing times 0.866. For 12 inch spacing, the sticks are 12 inches and 10.4 inches.
2. Lay out the first row. Run a string along one edge of the bed, set in from the edge by half the spacing. Mark plant positions along it with the long stick.
3. Mark the second row. Move the string over by the short stick. Start this row half a space along, so the first plant sits opposite the middle of the gap in row one. Then use the long stick again.
4. Repeat. Every odd row lines up with the first, and every even row lines up with the second.

A quicker way for small beds: place the first row, then position each plant in the next row so that it makes a triangle with two plants in the row behind. Check with the long stick that both sides of the triangle are equal to the spacing.

Set the plants out on the soil in their pots before you dig any holes. It is far easier to nudge a pot than to replant.

Spacing at the edges

Neither formula knows where the bed stops. Both assume the pattern runs on evenly. In practice, start the first row half a spacing in from the edge, so that each outer plant has room on its outward side.

For large beds, the formula count and the real count agree closely. For small or narrow beds, they can differ by several plants. A bed 2 feet wide planted at 12 inch spacing fits exactly two rows on a square grid, set 6 inches in from each edge. On a triangular grid at the same spacing, it still fits only two rows, since the third would land outside the bed. The formula would have predicted 15% more plants and been wrong.

So for narrow strips, count rows and plants directly, and treat the calculator’s figure as a check.

Rows that are not grids

Vegetables are often spaced differently within the row and between rows, for example 6 inches apart in rows 18 inches apart. That is neither a square nor a triangular grid. The count is:

At 6 inches by 18 inches, each plant has 0.5 × 1.5 = 0.75 square feet, so a 4 × 8 foot bed holds 32 ÷ 0.75 = about 43 plants.

And a single line of plants, such as a hedge or an edging, is counted by length. Divide the length by the spacing and add one, because there is a plant at each end.

Do not plant closer just because you can

A triangular grid fits more plants at the same spacing. That is different from planting closer than the tag suggests. Tag spacings are based on the mature width of the plant. Squeezing them tighter gives quick cover in the first year and crowded, disease-prone plants by the third.

If you want faster cover, use the triangular grid at the recommended spacing. You get the extra 15% without crowding anything.

Written and checked by Bertha
Last updated October 4, 2026 · How we work out our numbers