Planting trees & shrubs

Planting Tips

Planting Trees & Shrubs

Whether you’re planting a single tree or establishing a larger restoration area, good preparation and timing make all the difference. This page offers practical tips to help your trees and shrubs establish strongly and thrive for years to come.

Planning Your Planting

Start by visiting a nearby reserve or native forest to observe how plants grow together—their heights, colours, and shapes. In Christchurch, great spots include Riccarton Bush/Putaringamotu, the Port Hills Reserves, or reserves on Banks Peninsula.

Next, choose a spot in your garden where native plants can grow naturally without blocking sunlight, views, or interfering with power lines, pipes, or driveways.

Draw a plan of the area, noting existing trees, buildings, underground services, paths, and power lines. Try to imagine how your native garden will look in 5–10 years and consider future planting—such as species that will thrive in shade or need protection from frost and wind.

When planning plant placement:

Space larger trees 3m-5m apart
Space smaller trees, shrubs, and herbaceous plants 1.5m-2m apart

Label each plant with its name and location on your plan—this makes planting easier and ensures your garden develops as intended.

Site Prep

The key to successful planting is good soil preparation. Loosen compacted soil, remove rocks or debris, and, where needed, incorporate organic matter to improve drainage and fertility. Well-prepared soil allows roots to establish quickly and supports healthy, long-term growth.

In addition to soil prep, clearing weeds and other competing vegetation can further improve planting success. Herbicides, such as glyphosate (e.g., Roundup™) or other non-residual sprays, can be applied up to the day of planting, though treating the site 2–3 weeks beforehand often gives the best results and makes planting physically easier.

How to Plant

Dig the Hole: Make it about twice the size of the root ball so roots can spread easily. Width matters more than depth in heavy soils.
Prepare the Roots: Loosen tightly packed roots and trim any long ones to prevent circling.
Check Drainage: Ensure the hole drains well; on wet sites, mound the plant slightly above ground level.
Mix Soil: Combine any new soil, compost, or fertiliser with the existing soil—don’t just pile it at the bottom.
Plant: Set the plant at the same depth it grew in the nursery and firm the soil gently around the roots.
Water: Keep soil moist during establishment and dry spells—but don’t overwater. Sphagnum moss can help in dry areas.
Mulch: Apply 100mm of bark mulch around the plant to retain moisture and suppress weeds. Keep mulch away from the stem.
Aftercare: Check plants after strong winds and firm the soil if needed to prevent movement.

When to Plant

For best results, carry out major planting between April and September/October. Cooler months allow roots to establish before vigorous spring growth and the drying stress of summer.

In coastal areas and on light, sandy soils, autumn planting is often best (avoiding frost-sensitive species), as these sites dry out earlier. Adding sphagnum moss beneath the root ball can improve moisture retention.

Where planting relies on rainfall, timing is especially important. With irrigation, planting can extend over a longer period—however, avoid mid-summer heat where possible, or plant during the coolest part of the day.

Frost Considerations

In Canterbury, frost can be a major consideration when planting native trees and shrubs. Many native species tolerate light frosts, but harsh winter freezes—common in some inland areas—can damage young plants. To give your plantings the best start:

Check frost tolerance: Ask your nursery staff which species are hardy enough for your site.
Timing matters: Planting in autumn or spring can help avoid the harshest frosts.
Protect young plants: Use temporary shelters, mulch, or frost cloths to shield seedlings during cold snaps.
Site selection: Planting in slightly sheltered spots, such as near existing vegetation or on north-facing slopes, can reduce frost exposure.

Planning with frost in mind will help your native trees and shrubs establish strongly and thrive long-term.