About the Plant Spacing Calculator
Plants need room to grow, and the spacing printed on a seed packet is given in two numbers: the gap between plants in a row and the gap between rows. This calculator uses them with the length and width of your bed to work out the number of rows, the number of plants in each row and the total, so you know how many seedlings or bulbs to buy. Type the length and width of the bed and the two spacings and the plant spacing appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the Plant Spacing Calculator
- 1Enter the length and width of the bed and the two spacings.
- 2Pick the units or options from the menus if the plant spacing tool offers them.
- 3Read the plant spacing in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the plant spacing
Vegetable growers use it to plan beds before they buy seed, and landscapers use it to estimate the number of plants for a hedge or a border. It also helps with orchards, vineyards and bulbs.
The tool counts plants at the grid points, starting at the edge of the bed. If you want a margin at the edges, subtract it from the length and width before you enter them.
How the plant spacing is worked out
Plants per row = length ÷ spacing in the row + 1. Rows = width ÷ spacing between rows + 1. Total = plants per row × rows. A bed 10 metres long and 4 metres wide, with plants every 0.5 metres in rows 1 metre apart, has 5 rows of 21 plants, so 105 plants. Doubling the row spacing to 2 metres gives 3 rows and 63 plants.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- Rows, plants per row, total
- Any unit
- Two spacings
Mistakes to avoid with plant spacing
Use one unit throughout, such as metres or feet. Spacings on packets are for mature plants in typical conditions, so you may plant closer for baby leaves or further apart for large crops. Intercropping and staggered planting need their own plans.
On phone and computer
On a phone, type into the boxes one after another and read the plant spacing underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the plant spacing move. The plant spacing calculator works the same on both. The spacing tells you how many plants fit, and the soil comes next. Measure the bed with the Area Calculator, fill it with the Topsoil Calculator, and cover it with the Mulch Calculator.
Features
- Keep a margin at the edges
- Packet spacing is for mature plants
- One unit throughout
- Clear messages when the plant spacing inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate plant spacing?
Plants per row = length ÷ spacing in the row + 1. Rows = width ÷ spacing between rows + 1. Total = plants per row × rows. A bed 10 metres long and 4 metres wide, with plants every 0.5 metres in rows 1 metre apart, has 5 rows of 21 plants, so 105 plants. Doubling the row spacing to 2 metres gives 3 rows and 63 plants.
What is the formula for plant spacing?
Plants per row = length ÷ spacing in the row + 1. Rows = width ÷ spacing between rows + 1. Total = plants per row × rows. The plant spacing calculator applies it exactly and rounds only the displayed answer to six significant figures.
What is the difference between row spacing and plant spacing?
Plant spacing is the gap between plants along a row. Row spacing is the gap between the rows.
Should plants be at the edge of the bed?
Usually a little in, about half the spacing, so that the outer plants have room.
How many plants per square metre?
Divide 1 by the product of the two spacings in metres. For 0.5 and 1, 2 plants per square metre.
Is this plant spacing calculator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.