Planting trees guide

Private land makes up 58% of the total land area in the North Sydney local government area so what is planted on private property makes a significant contribution to the overall character and lifestyle quality of our suburbs. When you plant a tree, you are providing benefits to your whole community.

Species selection and tree placement are the two most important decisions when planting trees. Trees are very long-lived organisms. It can take a tree decades to reach maturity, but poor species selection or careless positioning can result in all those years being wasted. The best "return on investment" is achieved by planting the largest growing, longest-lived species that will successfully grow in the chosen location.

Site considerations

There are five essential requirements for tree survival:

• light
• water
• air
• nutrients
• space

Without an adequate supply of all of these, trees are unable to thrive. However different species have different requirements. Given the long-term nature of tree planting, obtaining expert advice may be a valuable investment.

Urban trees

In an urban setting, space for the fully mature tree is a primary consideration. This is not only for the trunk and branches, but also for the root system. Roots anchor the tree and extract nutrients and water from the soil. A healthy root system is key to a healthy tree.

Try it out

The difference between a small tree in the pot and a mature tree is immense, so before you plant, sit the pot in the proposed location and imagine it as the fully grown tree. It may look nice up against the wall while small, but is there room for the trunk to expand? is there room for the spreading branches? Are there overhead wires?

Tree species considerations

Tree purpose

Apart from being beautiful and improving the urban environment, trees can be used to do many things: frame desirable views, Screen unpleasant views, provide privacy, give shade, provide shelter from prevailing winds, provide habitat for local wildlife, add flower or foliage colour, add texture or scent, provide food, create a focal point, create separation etc.

So before selecting a species, work out what you want it to do and let this guide your decision about the size, canopy shape, growth habit and horticultural characteristics of your tree.

Deciduous trees

Deciduous trees lose their leaves in winter. This can be very beneficial for allowing sunlight through to adjacent buildings and reducing heating and lighting costs. It can also be helpful for trees growing in polluted or dusty locations, allowing the tree to grow a new, fresh, clean canopy each spring.

Tree forms

Planting in close proximity to Bushland

If you live near remnant urban bushland, it is important to select species that will not threaten the local ecology. Choosing locally indigenous species is the best option, but if for some reason none of these suit the space and desired function, it is imperative to choose a species that will not become an environmental weed or heavily overshadow adjoining natural areas.

Tree canopies across private land play an extremely important role in linking fragmented bushland areas, allowing native fauna to safely traverse our suburbs.

When planting in close proximity to bushland, sourcing trees grown from local seed can help protect genetic integrity. Specialist native nurseries can advise on provenance of their stock.

Climate change resilience

A lot of research is going on regarding which urban tree species will withstand climate change. Selecting species known to perform well in hotter, dryer climates than Sydney may be worth considering given the long term nature of tree planting.

Recommended tree species

The species list provided is not exhaustive and simply highlights those species that are known to grow well in North Sydney.*

The table is broken into four sections:

• locally Indigenous trees are those that are native to North Sydney.
• native trees are those that grow naturally in other parts of Australia
• exotic trees originate from anywhere else in the world
• traditional fruit trees

Mature heights in the table are estimates for that species in the growing conditions of North Sydney. Many species may grow taller in their natural habitat or in other climates.

*Australian Standard AS2303 – Tree Stock for Landscape Use - provides technical above and below the ground information to evaluate the quality of tree material grown by production nurseries. Make sure you buy trees from a reputable nursery where the plants are grown to meet these Standards.

Locally indigenous species

Other native species

Exotic species

Traditional fruit trees

Planting your tree

When to plant

Generally trees should be planted during spring or autumn. Autumn is the best as it allows the tree to settle in before the heat of summer. Only plant in Spring or Summer if you can really commit to looking after the tree during the hotter months.

How to plant

Make the hole twice as wide as the pot. Loosen up the sides of the hole and when you plant, make sure the soil level in the pot is level with the surrounding ground surface. Only tease or break up the root system if there is obvious ‘circling’ of roots. Mulch the soil surface when finished but do not put the mulch up against the trunk as this can cause rot.

Pruning at planting

Unless there are damaged branches, there is no need to prune at planting. As the tree matures it may be necessary to carry out careful selective pruning to ensure good form but this must be done with a thorough understanding of the natural shape of the species.

Staking

Trees in nature are not staked. They will grow to their natural form in response to site conditions and will be stronger if they are unsupported. However, in an urban setting, staking around the tree or installing a temporary barrier can be very beneficial to protect the tree from accidental damage, vandalism, strong winds etc.

Caring for your tree

Mulching and trunk protection

Mulch helps retain moisture in the soil, prevents weed growth and stabilises soil temperature. It is important to protect the trunk from mowers and whipper snippers as bumps from these create wounds allowing pest and disease entry, or even worse, can ringbark and kill the tree.

Watering your tree

As a rule, it is usually better to give a deep watering once a week rather than a little bit every day. Deep watering encourages a deeper, more resilient root system. Adjust the quantity and frequency in response to natural rain and take care not to overwater as too much water will kill a tree just as quickly as not enough.