Best Practices for Planting Trees and Shrubs

Getting a tree or shrub into the ground is only half the job. The real work – and where most failures happen – is in how you plant it. Planting depth off by just a few inches, roots crammed into a hole that’s too narrow, or a thick ring of mulch smothering the trunk can all quietly doom a plant that looked perfectly healthy the day you bought it. Whether you’re working with a bare-root sapling, a container-grown shrub, or a large balled-and-burlapped specimen, the principles are the same: minimize stress, protect the roots, and give the plant the best possible start in its new home.

Choosing the right planting method 🔗

Trees and shrubs are sold in three main forms, and each requires a slightly different approach. Matching your technique to the plant type reduces transplant shock and gives roots the space and conditions they need to establish quickly.

Bare-root plants 🔗

Bare-root plants are sold without soil around the roots, making them lightweight and affordable. According to Oklahoma State University Extension, bare-root plants should be dormant at the time of planting – not showing any new growth – and their roots must be kept moist from the moment of purchase until they go into the ground. If you receive them by mail, place the roots in water immediately, or temporarily heel them into a shallow trench covered with soil or straw until you’re ready to plant.

When you’re ready, dig a hole wide enough for the roots to spread out naturally without bending or circling. Cornell Cooperative Extension recommends mounding a small cone of soil in the base of the hole, setting the plant on top, and spreading the roots evenly over it. The root collar – where the roots meet the stem – should sit at or just slightly above ground level. Backfill gradually, firming soil gently around the roots to eliminate air pockets, then water thoroughly.

Container-grown plants 🔗

Container-grown plants have a wider planting window than other types because their roots are undisturbed. Oklahoma State University Extension notes that very little root loss occurs with container plants if they were grown in that container from the start, which makes them easier to establish. However, there’s an important check to do before planting: inspect the root ball for circling or girdling roots.

If roots have begun wrapping around the inside of the container, they need to be addressed before planting. University of Maryland Extension recommends using a utility knife to make four equally-spaced cuts down the length of the root ball, then pruning away any circling roots with hand pruners. Left untreated, these roots will eventually wrap around the trunk and strangle the tree. Horticulture experts stress that breaking up a pot-bound root pattern before planting is more important than any concern about temporarily disturbing the roots.

Dig the hole no deeper than the height of the root ball, but at least two to three times as wide. Remove all nursery stakes, labels, and container material. Place the plant so the root flare is at or just above existing soil grade, backfill with the native soil from the hole, and water well.

Balled-and-burlapped (B&B) plants 🔗

Balled-and-burlapped plants are dug from the field with their roots and surrounding soil intact, then wrapped in burlap to hold the root ball together. This method is common for larger trees and evergreens. Despite the protective wrapping, up to 90 percent or more of the root system may have been lost during digging, which is why careful handling and aftercare are critical.

Always handle B&B plants by the root ball, never the trunk. The Arbor Day Foundation advises digging a saucer-shaped hole two to three times as wide as the root ball and only as deep. Once the plant is in place and straight, the burlap needs to be addressed. UMass Extension recommends removing all rope, twine, and any synthetic burlap entirely, since synthetic materials will not decompose and can impede root development. Natural burlap can be cut away from the top and sides of the root ball; any remaining material beneath the ball will eventually rot. Wire baskets, if present, should have at least the top two to three rings removed once the root ball is stable in the hole.

Planting depth: the most critical factor 🔗

Planting too deep is one of the leading causes of plant failure, especially in clay or poorly drained soils. The rule is straightforward: the hole should be no deeper than the height of the root ball, measured from the trunk flare to the bottom of the root ball. The trunk flare – where the base of the trunk widens as it meets the root system – must be visible at or just above soil level after planting.

UMass Extension points out that in some nursery stock, the trunk flare may already be buried under soil or potting medium, so it’s worth digging down to locate it before you measure your hole depth. In wet or clay soils, it’s advisable to plant so the top of the root ball sits one to two inches above grade, then mulch the exposed portion to prevent drying.

A practical check: lay your shovel handle across the hole before planting. The trunk flare should be at or above the handle. If you’ve dug too deep, firm the soil at the base of the hole rather than leaving loose fill that will allow the plant to sink over time.

Spacing trees and shrubs correctly 🔗

Spacing is not just an aesthetic consideration – it directly affects air circulation, root development, and long-term plant health. Crowded plants compete for water and nutrients, are more vulnerable to disease, and become difficult to maintain. A useful baseline for shrubs is to space them at least half their mature width apart. A shrub that reaches four feet wide, for example, should be planted at least two feet from its neighbour. Additional clearance should be allowed near walkways, buildings, and structures – at least half the plant’s mature width between the plant and any fixed surface.

For trees, the University of Arizona Cooperative Extension recommends planning for the plant’s final size both above and below ground before choosing a location. Root systems extend well beyond the canopy – often two to five times the canopy width – so proximity to underground utilities, foundations, and drainage systems must be considered at planting time, not after the tree matures.

Handling plants to minimise stress 🔗

Transplant stress is unavoidable to some degree, but how you handle plants before and during planting makes a significant difference. Very fine root hairs, which are invisible to the naked eye, are responsible for most water and nutrient uptake – and they are killed almost immediately when exposed to dry air. For this reason, roots should never be left uncovered while you prepare the hole, and all plants should be thoroughly watered before planting if the root ball feels at all dry.

Avoid adding fertiliser or compost amendments to the backfill soil in the planting hole. University of Maryland Extension cautions that enriched backfill can cause roots to stay within the hole rather than spreading into the surrounding soil, limiting establishment. The native soil dug from the hole is sufficient for backfilling in most cases. Research also shows that fertilisation is unlikely to be effective during the first growing season unless there is a specific nutrient deficiency confirmed by a soil test.

Mulching after planting 🔗

Mulching newly planted trees and shrubs is one of the most beneficial steps you can take. The Morton Arboretum explains that mulch protects roots from temperature extremes, retains soil moisture, reduces weed competition, and improves soil structure as it breaks down. University of Minnesota Extension also notes that it reduces water evaporation from the soil, insulates against summer and winter temperature swings, and improves soil health over time by supporting microbial activity.

Apply mulch to a depth of three to four inches for medium- to coarse-textured organic materials such as wood chips or shredded bark. For newly planted trees, mulch beyond just the root ball – the goal is to encourage roots to spread outward, so mulching wide is more beneficial than mulching deep.

The single most important rule in mulching is to keep the mulch away from the trunk. Rutgers University’s New Jersey Agricultural Experiment Station explains that the tissue at the root flare cannot survive constant moisture and needs to breathe. When mulch is piled against the trunk – a practice widely referred to as “volcano mulching” – it restricts gas exchange, promotes rot, and can eventually kill the inner bark tissue, cutting off water and nutrient flow to the roots. Rutgers notes that over-mulching is a leading cause of decline in a wide range of landscape plants, including azaleas, dogwoods, hollies, and birch trees. Keep mulch at least six inches away from the trunk, and maintain a visible root flare.

Initial watering and establishment 🔗

Water is the single most important resource for a newly planted tree or shrub. UConn Extension recommends applying two to three gallons of water per inch of trunk diameter immediately after planting, with ongoing watering of around one and a half inches per week until the root system is established. Water should be applied slowly and at ground level so it can penetrate deeply rather than running off the surface.

University of Minnesota Extension recommends creating a shallow water reservoir by mounding soil three to four inches high at the edge of the root zone, which allows water to pool and soak in gradually. The rootball itself must stay consistently moist – bare-root and balled-and-burlapped plants can lose up to 95 percent of their root systems during transplanting, meaning the plant is relying almost entirely on the roots remaining in the root ball until new growth extends outward.

How long does establishment take? Research from the Morton Arboretum suggests approximately one year of establishment per inch of trunk caliper for trees in the northern United States, meaning a two-inch caliper tree may need consistent supplemental watering for two full growing seasons. Shrubs typically establish faster, often within one to two seasons. Rainfall alone is rarely sufficient – manual watering should only be skipped if there has been substantial rainfall of over one inch in a given day.

Avoid overwatering just as diligently as underwatering. In poorly drained soils, water can accumulate in the planting hole, displacing oxygen and causing root rot. University of Maryland Extension advises checking soil moisture several inches below the surface before watering – soil that appears dry at the surface may still be adequately moist at root depth.

A few more things to get right 🔗

Beyond the core techniques, a few additional steps improve outcomes significantly. Remove all nursery tags, wire ties, and labels from the plant after planting, as these can wound the trunk or restrict growth as the plant develops. Most newly planted trees do not need staking – staking should only be used if the plant genuinely cannot stand upright on its own in windy conditions, and any stakes should be removed within a year. Avoid pruning at planting time except to remove dead or broken branches; the plant needs its full canopy to support root development during establishment.

Timing also matters. University of Maryland Extension identifies fall, winter (provided the soil is not frozen), and early spring as the best planting windows for most trees and shrubs. Summer planting, when plants are in full leaf and transpiring heavily, places added stress on a root system that is already compromised from transplanting.

What do you think? Looking back at trees or shrubs you’ve planted in the past, do you think planting depth or post-planting watering had the bigger impact on how well they established? And if you had to choose one step from this process to be more careful about next time, which one would it be?

References

1. https://extension.okstate.edu/fact-sheets/planting-trees-and-shrubs.html
2. https://www.briarcliffmanor.gov/DocumentCenter/View/744/How-to-Plant-a-Tree-or-Shrub-PDF
3. https://extension.umd.edu/resource/planting-tree-or-shrub
4. https://www.milorganite.com/blog/trees-shrubs/planting-trees-and-shrubs
5. https://www.arborday.org/planting-your-tree/how-plant-balled-burlapped-trees
6. https://www.umass.edu/agriculture-food-environment/landscape/fact-sheets/guidelines-for-planting-trees-shrubs
7. https://www.thisoldhouse.com/landscaping/21017284/how-to-plant-a-shrub
8. https://extension.arizona.edu/publication/planting-guidelines-container-trees-and-shrubs
9. https://mortonarb.org/plant-and-protect/tree-plant-care/plant-care-resources/mulching-trees-and-shrubs/
10. https://extension.umn.edu/planting-and-growing-guides/watering-newly-planted-trees-and-shrubs
11. https://njaes.rutgers.edu/fs099/
12. https://homegarden.cahnr.uconn.edu/factsheets/tree-and-shrub-planting-guidelines/
13. https://www.hammondstar.com/lifestyles/use-good-techniques-when-planting-trees-and-shrubs/article_ff709450-bd7f-5bcd-93c5-b133424cd84e.html