Description
Hannonia hesperidium is a rare and very little-seen native of N. Africa, limited in the wild to rock-fissure and crags in a small area of western Morocco. Though said to grow on promontories around the Pillars of Hercules it appears to have been described originally from a much more westerly and southerly region on the Atlantic coast, around Cape Ghir. It is a monotypic genus and seemingly a relict from the early days in the evolution of the Amaryllidaceae. It is distantly related both to Pancratium and Lapiedra, but is distinct from both of those. It seems to be an evolutionary hangover from a time when it, or its relatives, were more widespread across the shores of the Mediterranean, before man and his familiar, the goat, turned the Sahara into a desert and forced the flora and fauna to either migrate or face extinction.
You might be forgiven for not having heard of Hannonia hesperidium as it is not only rare but it was only discovered for the first time in April of 1926 in the earth-filled holes of the limestone rocks at Tigert (now Tiguert) near Cape Ghir (a rocky promontory which is located about 40 km northwest of Agadir). It was described in 1931 (and then in French!) and has rarely been seen or heard of since.
It makes a smallish bulb clothed with thin pale tan, brownish or (eventually) blackish sheaths and 2-3 flat, fleshy, glaucous leaves with a characteristic little kink or twist to them. They are only some 2-5mm wide, but can reach 20cm long. It is said to flower in In March and April but we find it most usually flowers in summer (July) here. It makes a short stem bearing one or two flowers (we have had 4 in cultivation here). The oddness and unpredictability of the flowering season is just the plant avoiding the parched summer of its native home. In bloom it looks a little bi like some slender Sternbergia or even Narcissus (to which it is even more distantly related) except that the ephemeral flowers are usually borne in pairs and are pure white, (pure that is except for a thin green line that traverses each petal on the exterior). They open in the late afternoon and early evening (see Hesperus). Perhaps unusually for an evening-flowering white-flowered plant, they are scentless.
Unique in that it is the only member of its genus and although rare in cultivation it is readily grown in a pot of a very sharply-drained loam-based, but sandy, compost under frost-free glass such as an alpine house. It may take a little while to completely master them. They start re-rooting by mid-May and they will then need to be kept just ticking over during the summer to start flowering in late summer. In the early hot spell of June 2023 they remained totally dormant until mid August, in 2024 they flowered in July as expected. Hannonia is perhaps a little frost-tender but it is in no way “tropical”. It may also grow outside in a truly frost-free, Mediterranean garden in warmer climes but be warned it does need a dry summer with just that touch of moisture to keep the roots ticking over. It isn’t one for wet climates or wetness and it doesn’t like that much water even when it is seemingly in green growth during winter. In winter provide the best light possible.
Stock raised from material traceable to Gothenburg BG, their accession number is 1997-2424, but I have no further details than this.
