How far apart to plant trees, hedges and windbreaks

Crown width is the number that matters

Trees are planted small, so the room they need is easy to underestimate. What counts is the width of the crown at full size, which for many shade trees is 30 to 50 feet and for a columnar evergreen less than 10. Planting by that number is the only reliable way to avoid pruning, shading and root fights later.

How far apart should I plant trees?

For crowns that just touch at maturity, put the trunks half the sum of the two mature canopy widths apart. A tree 40 feet wide beside one 30 feet wide gives 35 feet. This is geometry, not a rule from a code. If you want the crowns to stay apart, plant farther. If you accept some overlap, plant closer, as in a windbreak or a screen.

How many plants do I need for a hedge?

The number of gaps is the length divided by the spacing, rounded down, and the plants are one more than the gaps, because both ends get a plant. A 60 foot hedge with plants 4 feet apart needs 16; at 3 feet it needs 21. For a closed loop, take one away.

How far does a windbreak protect?

The Natural Resources Conservation Service guidance says downwind benefits are usually found between 8 and 12 times the windbreak height, 10 times on average. Other USDA publications quote wider ranges, up to 10 to 20 times, so treat 10 times as a planning figure. It depends on how dense the planting is.

How far apart should windbreak rows be?

The NRCS windbreak standard (code 380) gives the distance between rows by what is planted: for example 10 feet between rows of low shrubs, 16 feet for tall trees next to a shrub row, 18 feet between two rows of tall trees, 20 feet between any tree and a conifer, and 25 feet between two rows of large conifers. The version here is Indiana's, from September 2022; other states issue their own.

How far apart in the row?

The same standard lists ranges, in feet: 3 to 8 for shrubs under 10 feet tall, 5 to 16 for shrubs and trees 10 to 25 feet tall, 6 to 10 for columnar trees such as cedar and arborvitae, 8 to 16 for trees over 25 feet and 14 to 24 for large conifers. Use the smaller figure for narrow crowns or when you need the benefit sooner, and the larger one for long life.

How far from the house should a shade tree be?

We found no figure we could verify in a university extension text, so this page does not state one. The crown geometry says the edge of the crown reaches half its mature width from the trunk, so a tree 40 feet wide has a crown reaching 20 feet from its trunk. Roots, foundations and sewer lines need more thought than the crown; ask your county extension office and check the local setback rules.

Is this for fruit trees or an orchard?

No. Orchard spacing depends on the rootstock and the training system, and the nursery or your extension service gives it for each variety. The mature-width rule here suits shade, screen and ornamental planting.

How the windbreak numbers fit together

The calculator takes the rows, the spacing between them and the spacing in a row from the NRCS standard, then counts plants as floor(length ÷ spacing) + 1 in each row. A 300 foot windbreak of 3 rows of tall trees, 18 feet between rows and 12 feet in the row needs 26 plants per row, 78 in all, in a strip 36 feet wide. If the trees reach 30 feet in 20 years, protection is expected 240 to 360 feet downwind, about 300 on average. Height is measured on the tallest row at 20 years, as the standard does.

Limits of the method

The 10-times figure is an average from field studies, not a guarantee. The NRCS Florida guidance sheet explains that the benefit depends on density, the number of rows, and how continuous the planting is, and with a density below 100 percent wind goes over, around and through the planting. A windbreak must also stay inside property lines, away from utilities, roads, fences and subsurface drains; the standard asks for a minimum of 50 feet from tile lines unless the pipe is protected. The spacing table is the Indiana edition; a state with a different climate may allow other spacing.

Common mistakes

Using the width of the tree today instead of at maturity, which is why young trees seem to have plenty of room. Counting the gaps and forgetting the extra plant at the end of the line. Planting a hedge on the spacing of a windbreak, or the other way round. Putting trees under power lines, over a septic field or close to a sewer, where roots cause trouble. Treating the 8 to 12 times height rule as a legal setback: it describes the shelter, not the distance to a boundary.

Sources: USDA Natural Resources Conservation Service, Conservation Practice Standard 380, Windbreak/Shelterbelt Establishment and Renovation, Indiana version, September 2022, table 1 (plant spacing) and the criteria on tile lines; NRCS Florida Field Office Technical Guide, Practice 380 Guidance Sheet, October 2011 (downwind protection 8 to 12 times the height, adapted from the USDA National Agroforestry Center’s Agroforestry Note 25). The crown-width rule and the count of plants are our own arithmetic. Related: plant spacing calculator, tree height calculator, fence calculator, mulch calculator. How we check our calculators.