The things I most disliked about Sicily were (a) being robbed; (b) the number of wild birds (especially goldfinches) hung up in tiny cages. On the plus side, there were plenty of things to like, including the Botanic Garden at Palermo.

The Orto Botanico was founded in 1779 by the Royal Academy of Studies (which later became the university of Palermo), and is now managed by the botany department of the university. It began as a small plot devoted to medicinal plants, but moved in 1796 to its present site, eventually occupying about 10 hectares. The neoclassical buildings at the entrance, with sphinxes and catyarids, were built a few years later, and in 1806 the politically controversial Queen Maria Carolina of Naples and Sicily (daughter of Maria Teresa and sister of Marie Antoinette) gave the garden a massive greenhouse or ‘winter garden’, originally in wood, now reconstructed in cast iron.

The façade of the ‘Gymnasium’ at the Orto.

The Maria Carolina glasshouse.

The sphinx theme is repeated in the garden’s flower pots.

The garden also contains the remains of the fourteenth-century church of St Dionysius, while other notable structural features included the Aquarium (1798), a circular pond divided into 24 segments, and the ‘Lagoon’ a wilder pond containing flourishing papyrus among other water plants. Both contain turtles, and sitting by the Aquarium I twice saw a kingfisher.

One of the many turtles in the garden ponds.

The garden has superb collections of cacti and succulents (if you like that sort of thing), citrus plants, cycads, and firs and pines.

One of the many outdoor benches of succulents.

A path through the citrus fruits.

More oranges.

It’s a wonderful place to wander slowly around, looking at exotic trees with thorns or fleshy leaves spiralling up the trunk,

Sorry, I didn’t note the name of this one!

towering palms, and the enormous strangler fig (Ficus macrophylla) which is the pride of the place – though I have to say that I don’t like these giant evergreens, thicket-like with their descending aerial roots, and huge, shiny leathery leaves.

The strangler fig, so called because it begins as an epiphyte on a host plant which it gradually swamps.

This one was brought from Norfolk Island in Australasia in 1845, and there is another in the grounds of Palazzo Chairamonte-Steri (ancestral home of the Norman Clairmont family, later (until 1782) the headquarters and prison of the Spanish Inquisition, and now the administrative headquarters of the university), which was planted in the 1820s.

The walls of the Inquisition cells show graffiti by the prisoners: several are in English.

Among the citrus are mandarin oranges (Citrus deliciosa), the trees originally brought in the early nineteenth century by the British navy from China to Palermo, whence they were distributed to other botanic gardens and to commercial growers, as was the loquat (Eriobotrya japonica), still grown in Sicily today. The large glasshouse has coffee, avocados, cinnamon, papaya, mimosa …

Loquat fruits.

But the small creeping serpent in this paradisiacal garden is a pretty little yellow flower which you first admire as an individual, and then observe with alarm as a large patch and then recoil from in horror as you realise that it is remorselessly overtaking bed after bed, invading any bare soil, and smothering any more delicate plants that may lie beneath.

Oxalis pes-caprae: pretty and innocuous?

Not when it spreads like this …

This monster is Oxalis pes-caprae, originally from South Africa, and now regarded as a noxious weed in many countries. It spreads by means of tiny bulbs (‘adventitious subterranean propagules’) which get left behind when you pull the parent plant up. (European oxalis, like ground elder, does it with rhizomes which re-sprout when broken, but the pernicious effect is the same.)

The root, showing the bulblets.

It has a variety of common names in English: sourgrass, soursob (not soursop, which is the fruiting Annona muricata), Bermuda buttercup, Bermuda sorrel, Cape sorrel, African wood-sorrel, or English weed, and goatsfoot – as in the Latin binomial, presumably because the leaves resemble cloven hooves? (The geographical adjectives sound as though everyone is blaming everyone else for the pest.) Its Italian name appears to be acetosella gialla, and once I’d got my eye in I was spotting in everywhere, worst of all in the Linnean systematic beds, which seemed completely overwhelmed.

It can theoretically be eaten, and is a folk remedy for tapeworm, though the oxalic acid can potentially kill livestock if they gorge on it. But what can the hapless gardener do? Scorching the top-growth with a weed-wand will not necessarily affect the underground bulblets, nor will weed-killers, and there seems to be no biological control, so it looks like a war of endless vigilance, slashing and hoeing, and possibly fine-sifting of soil – what a nightmare.

But I have to admit that, except from the point of view of good horticultural practice, it doesn’t spoil the overall effect of the garden, which on a bright sunny day is simply a glorious place. Just look at all this!

Caroline