Buying High-Quality Trees for NSW Replacement Planting

Not all nursery stock is created equal

For DA-required replacement plantings, council typically conditions consent on minimum pot size and species. What it doesn't do is ensure the stock you buy is actually good quality. Two trees of the same species in the same pot size can be vastly different in quality – one will establish quickly and become a productive landscape tree, the other will struggle and may need replacement within years.

The cost difference between high-quality and average stock is usually $30-$150 per tree. The cost difference in long-term outcome can be the entire planting being unsuccessful and having to be redone. Six quality factors matter most.

1. Trunk taper

A good young tree tapers naturally from a wider trunk base to a narrower top. Look at the trunk from base to first scaffold branch:

• Good taper: noticeably wider at the base than at the top of the lower trunk. Indicates the tree has developed strength under wind loading, has not been over-supported in the nursery.
• Poor taper: trunk diameter the same from base to top – often called "rake-handle" trees. Indicates the tree has been over-staked in the nursery and lacks structural strength.

Rake-handle trees often fail at planting or shortly after – they cannot self-support and frequently snap in their first storm.

2. Root structure

If you can lift the pot and check, look for:

• Good roots: firm, white or cream-coloured fine roots distributed through the soil. Some circling at the very pot edge is normal.
• Poor roots: heavy circling around the inside of the pot ("girdling roots"), thick roots emerging from drainage holes, roots that have grown a tight spiral that won't straighten when planted.

Girdling roots are a common cause of mid-life tree failure – the roots strangle the trunk as the tree grows. Pot-bound stock should be rejected.

3. Trunk form

Check the trunk for:

• Damage: scars, abrasions, sun-scald, insect tunnels. Any visible damage compromises long-term structure.
• Co-dominant leaders: two or more main trunks of equal size from low on the tree. These create included-bark unions that fail in maturity. For most species you want a single dominant central leader, not multiple leaders.
• Included bark in branch unions: Y-shaped unions where the branch bark ridge is folded INWARD rather than ridged outward. These are structurally weak.

4. Branch architecture

The branch arrangement on the young tree predicts the mature structure. Look for:

• Well-spaced scaffold branches: the main lateral branches should be spaced vertically along the trunk, not clustered at one level.
• Wide branch attachments: branches attached at angles closer to horizontal are stronger than branches attached at sharp upward angles.
• One dominant leader: for most species, you want one clear central leader with subordinate scaffold branches, not multiple competing leaders.

Formative pruning in the nursery is a sign of a quality producer. Many nursery operators don't do formative pruning, leaving the buyer with worse stock.

5. Pot size relative to tree size

Match the pot size to the apparent tree size. Common faults:

• Tree too small for the pot: indicates the tree was repotted recently and hasn't established in the new pot. Buy with the understanding it needs more time before planting.
• Tree too large for the pot: heavily pot-bound, will struggle to establish. The tree is too old for the pot size.

For NSW replacement plantings, council typically specifies a minimum pot size (commonly 100L for mature-tree replacements). The stock within that pot size should look proportionate.

6. General vigour and pest/disease signs

Walk past the obvious – look for:

• Foliage colour: appropriate for the species and season, not yellowed or dropping.
• New growth: recent flush at branch tips indicates active health.
• Pest signs: chewed leaves, sticky honeydew, webbing, scale insects.
• Disease signs: spots, blotches, dieback at branch tips.

A small amount of leaf damage from inevitable nursery pests is normal. Widespread or active infestation is not – skip that lot and look elsewhere.

What to buy where

Three quality tiers of nursery in NSW:

1. Specialist production nurseries (Acacia Hills, Andreasens Green, Heritage Trees, others): grow stock from seed/cutting on their own premises with formative pruning. Best quality but typically wholesale or trade only.
2. Established retail nurseries with their own production: mid-tier. Stock is good but variable.
3. Big-box garden centres or generic landscape suppliers: lowest tier. Stock often resold from larger producers, quality variable, formative pruning rare.

For DA-required replacement plantings, the time investment in selecting a Tier 1 supplier pays off. The Tier 1 stock has a better chance of establishing successfully within the council's required establishment period (typically 12-24 months), avoiding the need to re-plant if the first attempt fails.

Frequently asked questions