Ficus rubiginosa 'Variegata'

Where it comes from

Eastern Australia — New South Wales and Queensland, in Kew’s regions.¹ It is the Port Jackson fig, named for Sydney Harbour, and it is the only plant on this site that is a well-studied wild species in its own right rather than a houseplant with a wild ancestor.

It is a strangler, and unusually that is documented for this species rather than borrowed from figs generally. A 2014 study describes three growth forms: a lithophyte of 1-5 m on rock, a free-standing tree over 15 m, and a rainforest strangler over 25 m.² The regional flora key opens its entry with “at first epiphytic or growing between or over rocks”.³ Maximum size is contested by a factor of five across sources, which is what happens to a tree that grows differently depending on what it germinated on.¹²

The gap between that and a pot is the point. The RHS gives the cultivar an ultimate height of 1.5-2.5 m over ten to twenty years, grown under glass or as a houseplant.⁴ A 30 m strangler is what this plant is; 2 m in a container is what it does when you stop it. For a picture of the difference, the National Trust lists one growing on top of the bluestone wall of the Old Melbourne Gaol — 20 m tall, about ninety years old, held up by its own aerial roots.⁵

Naming and description

Desfontaines described it and Ventenat validly published it, in Jardin de la Malmaison — and the date usually given is wrong. IPNI puts the protologue at volume 2, part 19, plate 114, August 1805, and POWO agrees.⁶¹ The widely repeated 1804 comes from the volume rather than the plate.

Rubiginosa means rusty, for the indumentum on the leaf underside: the NSW flora describes the lower surface as “mostly hairy and rusty-coloured”, with rusty-hairy young stems.⁷ The variegated form keeps it — UF/IFAS describes the underside as brown and hairy for both the cultivar and the plain species, which makes sense, since the variegation is a chlorophyll defect and not a change to the hairs.⁸⁹ But the character does not identify the species by itself: the flora’s key uses it only to separate this species and F. macrophylla from the glabrous ones, and then calls rubiginosa “extremely” variable¹⁰, with some trees glabrous and approaching F. platypoda.⁷

That confusion runs the opposite way to how it is usually told. F. platypoda is a good accepted species with no rubiginosa names in its synonymy; it is four of platypoda’s own varieties that are now synonyms of rubiginosa.¹¹¹ The other name still in circulation is Ficus australis Willd., a heterotypic synonym.¹

One name to drop: “little-leaf fig” is not a name for this plant. The Atlas of Living Australia gives Port Jackson fig, rusty fig, Illawarra fig, figwood and Botany Bay fig.¹² “Small-leaved fig” is Ficus obliqua — the species this one has historically been confused with.¹³

‘Variegata’ is not a registered cultivar anywhere reachable: there is no registration authority for Ficus, the Australian native-cultivar registry has no Ficus entries, and both a name search and the complete US plant-patent class listing for the genus came back empty.^14151617 The RHS holds a plant record, but that records commerce rather than registration.⁴

Fun facts

• This cultivar has a peer-reviewed paper of its own, and what it found is stranger than “it’s a chimera”. Beardsell and Norden sectioned F. rubiginosa ‘Variegata’ and confirmed a GWG periclinal chimera — the chlorophyll deficiency sits in the second meristematic layer, which is most of the mesophyll.¹⁸ The surprise is where the green patches scattered through the white tissue come from: not from L2 at all, but from vascular bundle sheath cells, which are L1-derived, dividing sideways back into the mesophyll.¹⁸ Two different meristematic origins of green tissue in one leaf. This is the only variegation histology published for any Ficus.
• The same paper puts numbers on two things growers only guess at. Reversion to all-green happens in roughly one shoot in a hundred, and untended trees carry a few fully green branches as a result. And the variegation is seasonal: winter leaves averaged 286 green patches per leaf on the upper surface against 86 in summer, and 155 against 10 underneath.¹⁸ A plant that looks greener in July is not reverting.
• Its pollinator turned out to be five species, none of them formally described. Pleistodontes imperialis was found to contain four deep mtDNA clades differing by 9-17 per cent — overlapping the divergence seen between recognised Pleistodontes species — and both mitochondrial and nuclear data show they split without ever changing host plant.¹⁹ The count now stands at five.²⁰ Three of them coexist near Townsville with about 13 per cent of figs holding two or three species at once and no gene flow between them.²¹ Clade diversity falls from all four in north Queensland to one at Sydney.¹⁹ The literature still calls them “sp. 1” to “sp. 5”. The tidy one-fig-one-wasp story taught everywhere is, in general, a simplification.²²
• When the tree emigrated, one wasp came with it. Sampling in mainland Spain, Tenerife and California found the mutualism re-established and ripe fruit being produced — and every introduced wasp is sp. 1, with almost no genetic diversity, traceable to the Sydney region.²⁰ None of the twenty-odd native non-pollinating wasps made the trip. In New Zealand the wasp arrived in the 1980s,²³²⁴ in Hawai’i it was introduced deliberately in 1922 as a forestry measure,²³ and in Greece and Cyprus it has since been found switching hosts onto a different fig.²⁵ In Malta, planted since the early 1990s, the trees have never been seen to fruit — no wasp.²⁵
• New Zealand has banned it. It is on the 2020 National Pest Plant Accord, which prohibits sale, propagation and distribution.²⁴²⁶ A tree that cannot reproduce is a garden plant; one whose pollinator has followed it is a weed, and that is the whole difference.
• There is no toxicity evidence for this species at all, which is worth saying plainly. The ASPCA has no entry for it, and NC State has no page — the URL that would follow their pattern 404s.²⁷ So there is no severity rating to quote, and any “toxic to cats and dogs” you read is extrapolated from the genus. What does exist: the RHS flags ‘Variegata’ as a skin allergen and says to wear gloves,⁴ and a Californian flora notes possible skin irritation from the sap.²⁸ The whole Ficus allergy literature is about F. benjamina.