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Mandarin Rootstocks Used in Australia

Mandarin Rootstocks Used in Australia explained for Australian readers, with local season, shopping, growing, recipe, nutrition, or industry context.

By Mandarins.com.au Editorial Updated 1 June 2026

The rootstock is the lower part of a grafted citrus tree, from the roots to the graft union. It determines how big the tree grows, how it handles soil conditions, whether it tolerates cold or waterlogging, and how resistant it is to soil-borne diseases. The fruiting variety grafted onto it determines what fruit you get. Both matter.

Most mandarin trees sold at Bunnings, Engall’s, Daley’s, and nurseries across Australia are grafted. Knowing what rootstock a tree is on helps you choose correctly for your soil and space.

What rootstock does

Rootstock affects:

  • Tree size: dwarfing rootstocks keep trees small; vigorous rootstocks produce large trees.
  • Disease resistance: some rootstocks resist Phytophthora root rot; others are susceptible.
  • Soil tolerance: different rootstocks suit clay, sand, salt-affected soils, or alkaline soils.
  • Cold tolerance: some rootstocks harden the tree against frost.
  • Fruit quality: rootstock can slightly influence fruit size, skin thickness, and sweetness.
  • Graft compatibility: not every variety can be grafted onto every rootstock.

Citrus Australia recommends that growers source budwood through Auscitrus to ensure budwood is free from graft-transmissible pathogens such as exocortis and psorosis.

Trifoliata (Poncirus trifoliata)

Trifoliata is a cold-hardy, deciduous rootstock used widely in southern Australia, particularly in Melbourne and Adelaide. Leaf Root & Fruit Gardening Services recommends it for Melbourne home growers because of its tolerance of the wet winters and cold soils common in that region, and its good resistance to Phytophthora root rot.

Trifoliata produces a moderately sized to full-size tree depending on the scion. It is not dwarfing on its own, but it produces a more contained tree than some vigorous rootstocks.

Known issue: Imperial mandarin on Trifoliata rootstock can develop an incompatibility at the graft union over time. Leaf Root & Fruit notes that this incompatibility can cause abnormal growth at the graft union and may eventually kill the tree at around 15 years post-grafting. This incompatibility can be managed by using a sweet orange interstock between the Trifoliata rootstock and the Imperial scion. Ask your nursery whether this interstock has been used if you are buying Imperial on Trifoliata.

Troyer and Carrizo Citrange

Troyer and Carrizo are both hybrids of Poncirus trifoliata and sweet orange (Citrus sinensis). They are widely used in Australian commercial orchards and are common rootstocks for retail nursery trees.

Both are vigorous, cold-tolerant, and handle a wide range of soil types. Carrizo is slightly more vigorous than Troyer and is often preferred where yield and orchard size are priorities. Both are resistant to Citrus Tristeza Virus (CTV), which is important for commercial plantings.

Trees on Troyer or Carrizo produce full-size canopies. They are well suited to most Australian growing conditions outside the tropics.

Cleopatra mandarin rootstock

Cleopatra mandarin (Citrus reshni) rootstock is listed on the Citrus Australia varieties and rootstocks page as a commercial option. It produces a vigorous tree and has reasonable salt tolerance, making it suitable for some coastal or bore-water irrigated sites.

It is less common in backyard tree retail than Trifoliata or Citrange rootstocks.

Flying Dragon (dwarfing)

Flying Dragon is a variant of Poncirus trifoliata that naturally produces much smaller trees than standard Trifoliata. It is the main dwarfing rootstock used for container and small-garden citrus in Australia.

Trees on Flying Dragon stay under 2 metres in-ground and can be maintained smaller in pots through light annual pruning. They are cold-hardy, moderately resistant to Phytophthora, and compatible with most common mandarin varieties.

At Engall’s Nursery and Daley’s Fruit Trees, dwarf mandarin trees are grafted onto Flying Dragon. The Daley’s product page for Dwarf Mandarin Imperial specifies suitability for a 35-litre or larger pot, with a maximum in-ground height of 1 to 2 metres.

Note: Flying Dragon is compatible with most mandarin varieties, but graft compatibility should always be checked. The QP Seedlings budwood guide lists Flying Dragon as having high compatibility with both standard mandarins and Satsuma.

What Australian nurseries sell

Retail nurseries in Australia generally do not label the rootstock on standard-sized trees, though dwarf trees often indicate Flying Dragon on the label or product description.

When buying a full-size mandarin tree from Bunnings or a local nursery:

  • The rootstock is likely to be Trifoliata, Troyer, or Carrizo.
  • Ask the nursery staff what rootstock the tree is on, particularly if you are buying Imperial mandarin for a Melbourne or Adelaide garden (where the Trifoliata incompatibility issue is relevant).
  • For specialist varieties or dwarf forms, Daley’s Fruit Trees and Engall’s Nursery provide more rootstock detail.

How to ask the nursery

When buying a mandarin tree, ask:

  1. What rootstock is this grafted on?
  2. Is this tree on Flying Dragon (if you want dwarf) or on a standard rootstock?
  3. For Imperial mandarin: is there an interstock between the rootstock and the scion?

A nursery that cannot answer these questions at all may be selling trees from suppliers who do not track rootstock provenance. Specialist citrus nurseries such as Engall’s will know their stock.

For home gardeners, the rootstock choice primarily matters if you:

  • Want a dwarf tree (ask for Flying Dragon)
  • Are in Melbourne or Adelaide buying Imperial (ask about Trifoliata compatibility)
  • Have heavy clay or waterlogged soil (ask for Trifoliata or similar)
  • Are in a very cold area (Trifoliata or Troyer/Carrizo are appropriate)