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Gentiana acaulis Family: Gentianaceae The spring-flowering Gentiana acaulis was the first gentian to be featured in the Botanical Magazine, appearing in the second volume in 1788. This species is found in the Balkans and the mountains of southern and central Europe, including the Alps, Pyrenees and Carpathians. Its habitats include rocky meadows, screes and alpine and subalpine coniferous forests at altitudes of 1,700–3,000 m (5,577–9,843 feet). Gentiana acaulis is likely to have been introduced into cultivation in the eighteenth century. Its large, trumpet-shaped flowers are held close to the mat of lanceolate or elliptic leaves on a short stem, which elongates when the plant is in fruit.These glorious, deep blue flowers can reach up to 7 cm long and have green spots in the throat.The five-pointed corolla lobes are 6–9 mm long and are separated by small triangular lobe-like plicae. This is one of the ‘Acaulis group’ of gentians, which comprises species with very short stems, so the flowers appear to sit directly on the mat of leaves. The other species in this group differ from Gentiana acaulis in the shape of the leaves, the shape of the sepals and their size relative to the corolla, and the markings on the inside of the flower. Gentiana kochiana and G. excisa have been included in the ‘Acaulis group’ but are more often treated as synonyms of G. acaulis. Gentiana acaulis is best grown in an exposed position in full sun, firmly planted in soil that doesn’t completely dry out. Additional watering may be necessary during dry periods. In less exposed situations, the mat of leaves can become loose and the stems may elongate. The stem of G. acaulis is very short at first, but by the time the seeds are ripe it can be 15 cm long. It is often stated that Gentiana acaulis can be shy to flower. Where this proves the case, planting in different locations is worth a try in order to find a place where the plant is happy. Alternatively, it may be that the grower possesses a clone that rarely or never blooms, so new material should be sought. Over the years, many authors have suggested feeding to encourage blooming, and a high potash liquid fertiliser, applied in midsummer and again in early spring, is well worth trying. The normal flowering period is from March to May but the odd flower can appear throughout the summer and well into autumn. Established plants will form a dense carpet of leaves and regular division may be needed to keep them flowering. Gentiana acaulis and the rarely cultivated G. alpina grow naturally in acidic soils but they will tolerate mildly alkaline conditions. Other allied species, such as G. clusii and G. occidentalis, are lime-lovers.
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Alpines from Mountain to Garden
The tendency for Gentiana acaulis to produce stolons and runners ensures a good supply of material for cuttings. From midsummer onwards, remove rosettes of leaves with a short portion of stem and pot them into a free-draining cuttings mix. Propagation from seed sown in autumn is also straightforward, as long as the seed is fresh.
Curtis’s Botanical Magazine, plate 52 (1788). Artist: James Sowerby.