Tree Spacing Calculator
Calculate how many trees you need for a row or property line from the row length and your desired spacing between trees.
How this calculator works
Spacing out a row of trees is really a division problem: how many equal gaps of your chosen size fit along the row, plus the tree that starts the row off. This calculator takes your row length and desired spacing and returns the number of trees needed to fill it evenly.
Formula: Number of trees = floor(row length ÷ spacing) + 1 (one tree at each end plus the ones in between).
Worked example
A 100 ft row with trees spaced 20 ft apart:
- Row length: 100 ft
- Spacing: 20 ft
- Gaps: 100 ÷ 20 = 5
- Trees: 5 + 1 = 6 trees
Notes
Spacing needs vary hugely by species and purpose. A privacy screen of something like arborvitae might go 3-5 ft apart to grow into a dense, continuous hedge. Shade trees like oaks need much more room — 30-40 ft or more at maturity — to avoid their canopies crowding each other as they grow.
Check your specific species’ mature spread before settling on a spacing number. A tree that looks properly spaced as a young sapling can end up competing for light and root space with its neighbors once it reaches full size, which is a much harder problem to fix after the fact than before planting.
How to use
Enter the total length of the row or property line and the spacing you want between trees, both in the same units. The calculator returns the number of trees needed to fill the row evenly, with one tree at each end.
A layout planning estimate. Confirm mature spacing requirements for your specific tree species before planting.
Frequently asked questions
How many trees do I need for a row of a given length?
Divide the row length by your chosen spacing, then add 1 for the tree at the far end. A 100 ft row with trees spaced 20 ft apart gives 100 ÷ 20 = 5, plus 1 = 6 trees, including one at each end of the row.
Why do I add 1 to the row-length-divided-by-spacing number?
The division tells you how many spacing gaps fit along the row, but a row of trees has one more tree than it has gaps between them — think of a fence with posts at both ends. Adding 1 accounts for the tree placed at the starting end of the row.
How far apart should I space trees?
It depends heavily on species and purpose. A privacy screen of something like arborvitae might go 3-5 ft apart to fill in as a dense hedge, while shade trees such as oaks need 30-40 ft or more at maturity so their canopies don't crowd each other.
What happens if I plant trees too close together?
Trees planted too close will eventually compete for sunlight and root space as they reach mature size, even if they look appropriately spaced as young saplings. Checking your specific species' mature spread before planting avoids having to remove or transplant crowded trees years later.
Estimates only. Verify quantities with your supplier before purchasing.