How to plant trees and shrubs on a slope or a steep bank

How to cut a level shelf and basin for each plant on a hillside, which mulch and matting stay put, what grows on a dry or shady bank, and how live stakes root.

To plant a tree or shrub on a slope, cut a level shelf into the hill for each plant and stand it upright there, its root flare at the shelf’s surface. Firm the loose soil into a low ridge on the downhill edge, so water soaks in instead of running off. Cover bare ground the same day with coarse mulch, or a jute or coir blanket where it would wash. Choose natives for the slope’s light and soil. On a stream bank, dormant cuttings of willows and dogwoods pushed into the wet soil take root and hold it.

A regraded stream bank under a pinned erosion blanket, rows of thin stakes in it and cut logs along the water’s edge — A stream bank regraded and covered with an erosion control blanket on March 5, 2013. Logs line its toe, the part of a bank that takes the scour of high water. Photo: U.S. Fish and Wildlife Service Southeast Region, Public domain (source)

Read the slope before you dig

Steepness is rise over run, the feet the ground climbs over a level distance:

Slope	Rise over run	Percent	What it means for planting
Gentle	Under 1 in 20	Under 5	Few special needs
Moderate	1 in 12 to 1 in 6	8–16	Water runs off before it soaks in
Steep	1 in 5 or more	20 or more	Needs special planting
Too steep to mow	1 in 3 or more	33 or more	Plants in place of lawn grass
Near the limit	1 in 2	50	Often the steepest ground plants hold

Steep ground is usually dry, since rain runs off it, while its foot is often wetter. Before planting, turn away any water a downspout or a driveway sends onto the slope.

A tangle of pale bare roots snaking over a slope where the soil has washed out from between them, ferns among them — Roots laid bare where a slope's soil washed out, on May 3, 2023. How much a slope erodes turns on its steepness, its soil, its plant cover and the water running onto it. Photo: Blue Whale Trees

A level shelf for each plant

Plant in fall or early spring, as when to plant a tree explains. Each tree or shrub gets a small terrace of its own, dug by hand:

Leave the cover between plants. Kill turf in place and plant through it, since dead grass and its roots hold the soil while new roots grow. Turning lawn into a native planting gives the ways to kill it.
Cut the shelf. Dig into the uphill side and spread that soil downhill until the shelf is level and two to three times as wide as the root ball.
Dig the hole. Make it no deeper than the root ball measured from the root flare, and two to three times as wide.
Stand the plant upright, its flare at the shelf’s level surface. A tree tilted to match the hill takes many years to grow upright again.
Build the ridge. Firm the loose soil along the downhill edge into a low ridge that holds water over the roots, with stones or bricks to keep it from washing out.
Face the cut with a few stones, since soil washing down from the uphill wall can bury the flare.

Stagger the plants rather than lining them up down the slope, and run any rows across it, so water cannot run down a row. Planting distances gives each species’ spacing.

Mulch and matting that stay put

Bare soil between new plants washes away first. Spread 2 to 3 inches of mulch over each shelf, kept back from the trunk as mulch around a tree sets out. Pine needles interlock and stay put on a slope, and shredded hardwood does not wash away easily. Bark chips and river rock are more likely to wash downhill.

An eastern red cedar leaning from a steep bank over water, its roots bared where the soil has washed away — A bank over water on May 20, 2024, its soil washed from around an eastern red cedar's roots. Bare soil washes away most easily while new plants are still rooting. Photo: Blue Whale Trees

Where bare soil would wash, an erosion control blanket holds it until the plants cover it. Burlap, jute and coir rot in place, while the plastic mesh of many blankets takes 3 to 24 months of sun to break down. Pin the blanket tight with landscape staples right after planting, since plants lift a loose one.

Natives for a dry slope and a shaded one

A mix of sizes and root types holds a slope best, since leaves at several heights break heavy rain and roots of several kinds grip the soil. Several shrubs below hold a bank by spreading into colonies. The wet foot of a slope takes the natives that hold a stream bank and those that take wet feet.

Low mats of creeping juniper spreading across a pale rock outcrop, with dry grass and bare stone between them — Creeping juniper spreading in low evergreen mats over rock in the wild. Ground covers like it are particularly good at covering the soil surface of a slope. Photo: Gilles Ayotte, CC BY-SA 4.0 (source)

A dry, sunny slope

Fragrant sumac, for a sunny slope too dry and rocky for grass. Zones 3 to 9, 2 to 6 feet.
Black huckleberry, whose colonies hold a rocky hillside. Zones 3 to 7, 1 to 3 feet.
Creeping juniper, an evergreen mat for dry, open slopes. Zones 2 to 9, 1 to 2 feet.
Staghorn sumac, which suckers into a grove on dry banks. Zones 3 to 8, 15 to 25 feet.
Chestnut oak, an oak of dry ridgetops and upper slopes. Zones 4 to 8, 50 to 70 feet.

A shaded slope under trees

Under trees, the canopy and fallen leaves already break the rain, so the ground need not be covered edge to edge. Dig little among the roots and set out small plants, as what to plant under a big tree explains.

Canada yew, an evergreen whose mass helps hold a shady slope. Zones 2 to 7, 3 to 6 feet.
Mountain doghobble, an evergreen that spreads into thickets on a shady bank. Zones 4 to 8, 3 to 6 feet.
Red elderberry, for a north-facing slope. Zones 3 to 7, 8 to 12 feet.
Hop hornbeam, an understory tree for a dry slope under old oaks. Zones 3 to 9, 25 to 40 feet.
Striped maple, for a cool, north-facing slope under tall hardwoods. Zones 3 to 7, 15 to 35 feet.

Dark green masses of Canada yew spreading over a steep wooded bank of leaf litter under leafless hardwoods — Canada yew spreading in patches over a wooded bank. In a forest even soil that looks bare is likely full of tree roots, which hold it in place. Photo: Gilles Ayotte, CC BY-SA 4.0 (source)

Live stakes for a stream bank

A live stake is a dormant stem cut from a willow or a shrub of wet ground and pushed into a stream bank, where it roots. It is a cheap way to root a raw bank, but only where the stake reaches saturated soil.

Which natives root from a cut stem

Willows root easily from stem cuttings, and Penn State Extension names black willow, red osier dogwood and silky dogwood as the three most used in the Northeast. To test any other shrub, stand a thin cutting in a jar of water on a sunny windowsill: roots within two to three weeks mark a plant to stake. We do not grow black willow, but we grow these as rooted plants:

Silky dogwood, which keeps a bank from washing out after two or three years. Zones 4 to 8, 6 to 12 feet.
Red osier dogwood, which roots where its stems lie. Zones 2 to 7, 6 to 12 feet.
Buttonbush, whose dense stands hold a shoreline. Zones 4 to 10, 5 to 12 feet.
Black elderberry, which holds moist soil beside streams. Zones 3 to 9, 6 to 12 feet.
Ninebark, whose roots hold a creek bank. Zones 2 to 8, 5 to 10 feet.

Long, narrow, finely toothed black willow leaves on drooping twigs against a blue sky — Black willow's long, narrow leaves on October 22, 2026. Black willow, elderberry and buttonbush are among the plants most often cut for live stakes. Photo: Blue Whale Trees

Cutting and setting the stakes

Cut stakes while the plants are dormant and the soil is not frozen, from November to February in North Carolina and into April in Pennsylvania. Take straight stems ½ to 1½ inches thick and 2 to 3 feet long, angled just below a bud at the bottom and flat at the top. Strip the side shoots, take no more than 5 to 10 percent of any plant, and ask first on land not yours. Keep the stakes in water out of the sun until they go in, the same day if you can.

Set them from just above the water up the bank, no higher than the soil stays wet, with a rebar pilot hole in hard soil. Push each stake in square to the bank, buds up and tipped slightly downstream, until half to three quarters of it is underground. Start on the outer bends, which erode most, and space the stakes 2 to 3 feet apart in a staggered pattern, closer on raw ground, since some will fail:

“Live stakes are planted more densely than these tree species normally would be because there is an expectation that not all of the stakes will survive.” (Penn State Extension, Live Staking for Stream Restoration)

Where rooted plants do better

On a bank more than 4 to 5 feet high, stake the bottom 2 to 3 feet and plant rooted seedlings above, since they need no saturated soil. Blue Whale Trees grows the five staking shrubs above from seed and ships them as rooted saplings, not cut stakes. Reshaping the bank or the channel is work for an engineer and can need a state permit.

A slow creek between steep banks lined with trees and shrubs leaning out over the water — A creek between banks held by trees and shrubs on September 27, 2026. At the top of a bank taller than 4 or 5 feet the soil is not saturated, so stakes there seldom root. Photo: Blue Whale Trees

Watering through the first year

Drip lines and soaker hoses water a slope best. Without them, water in rounds:

“When drip irrigation is unavailable, water plants until excess water begins to run down the slope. Move on to the other plants and circle back to re-wet them.” (Iowa State University Extension and Outreach, Gardening on Slopes and Hillsides)

Repeat until the root zone is wet through. The watering calculator gives the gallons and how often until the tree is established. After each heavy rain, pull back any soil washed onto a flare.

Stakes need water in a dry first summer too, and they may show few leaves while they root. Judge them in the fall, when a gentle tug on a few shows which have rooted. Fill the gaps in a later winter, and after a flood, clear the debris and replace any that washed out.

Where to start

Choose the plants: the tree finder lists the natives we grow that hold soil, by zone, sun and soil moisture.
Compare them: the shop’s erosion control list shows their zones and heights side by side.
A dry, sunny bank: the Dry Sandy Site Pack sets six shrubs for zones 4 to 7 together, staghorn sumac among them.
A wet corner: the Wet Spot Pack sets six natives of wet ground together, silky dogwood among them.

Common questions

How do you plant a tree on a steep slope?

Cut a level shelf two to three times as wide as the root ball, and set the tree upright with its root flare at the surface. Firm the loose soil into a low ridge on the downhill side, and mulch the shelf.

What shrubs are best for erosion control on a slope?

Fragrant sumac and creeping juniper hold a dry, sunny bank, and Canada yew a shaded one. Silky dogwood and buttonbush hold a bank that stays wet.

What is the best mulch for a slope?

Pine needles and shredded hardwood stay put on a slope better than bark chips or river rock, which wash downhill. Spread 2 to 3 inches and keep it back from the trunk.

When should live stakes be planted?

While the plants are dormant and the ground is not frozen, from November until just before the buds break in spring. Stakes set after the plants leaf out root less often.

Gardening on Slopes and Hillsides: Iowa State University Extension and Outreach, Yard and Garden: slopes by rise over run and what each grade means, drier slopes with a wetter foot, water turned away at the top, turf killed and left in place, terraces 2 to 3 times as wide as the root ball, stones to hold the cut and the fill, trees set upright, plantings staggered across the slope, mulches that stay put, erosion blankets, a mix of plants and roots, ground covers that cover the soil, and the quotation on watering in rounds with a basin on the lower side.
Native Plants for Shady Slopes: University of Maryland Extension, Home and Garden Information Center, with its page Planting a Tree or Shrub: the canopy and fallen leaves that shield a shady slope, little digging among tree roots and small plants set out there, forest soil full of tree roots, and a hole no deeper than the root ball measured from the root flare.
Livestakes: Easy Propagation for Streambank Plants: Clemson Cooperative Extension, Home and Garden Information Center (Katie Collins and Karen Jackson, HGIC 1907, 2025), with its factsheet Mulch (HGIC 1604): stakes cut in the dormant season with the owner’s permission, 2 to 3 feet long, an angled bottom and a flat top, storage in water, stakes tilted downstream, the outer bends at most risk, watering in a dry first summer, and pine needles and shredded hardwood that stay put on a slope.
Live Stake Installation Guide: NC State University, Biological and Agricultural Engineering Extension, from NC State Extension of Henderson County: November to February for cutting and planting, an angled cut below a node, stakes kept wet and planted within 24 hours, rebar pilot holes from just above the water, buds up, three quarters of the stake in the ground, and 2 to 3 feet between stakes.
Live Staking for Stream Restoration: Penn State Extension, with its pages Live Staking: A How-to Guide and Common Live Stake Species for Residential Stream Repair: the three species most used in the Northeast, ninebark, buttonbush and elderberry as staking species, stems ½ to 1½ inches thick, 5 to 10 percent of a source plant, November to April in Pennsylvania, stakes planted the same day, half to two thirds in the soil, no higher than the water table, the quotation on dense planting, roots before leaves, the tug in the fall, and stakes replaced after a flood.
Improving Stream Channels, Ditches and Lakeshores With Live Staking: University of Tennessee Extension (Andrea Ludwig, SP 781-B, 2015): stakes that root only in saturated soil, tall banks staked at the bottom and planted with rooted seedlings above, the jar test for rooting, stakes set while the soil is not frozen, at right angles to the bank and tipped downstream, closer spacing on a raw bank, the lower success of stakes set after dormancy, the toe of a bank that takes the scour of high water, and the engineer and the permit for reshaping a bank.
Salix L., willow (PDF): USDA Forest Service, Woody Plant Seed Manual, Agriculture Handbook 727 (Zasada, Douglas and Buechler, 2008): the ease with which willows root from stem cuttings.

Planting trees and shrubs on a slope or a bank

Read the slope before you dig

A level shelf for each plant

Mulch and matting that stay put