| Autumn gentians | Information |
|---|---|
| Common name: | autumn gentians |
| Botanical name: | Gentiana sino-ornata |
| Family: | Gentianaceae |
| Type: | semi-evergreen alpines |
| Flowering season: | autumn |
| Planting season: | spring |
| Height: | 5-10cm (2-4in) |
| Spread: | 10-35cm (4-14in) |
| Aspect: | Sun |
| Hardiness: | H5 |
| Difficulty: | Easy to average |
When most people think of gentians, they envision the bright-blue flowers that bloom in the Alps during spring. But there is another gang of gentians, which looks similar, but hails from Asia and flowers now, in autumn. The best garden forms of these autumn gentians are Gentiana sino-ornata and its hybrids. A low-growing semi-evergreen perennial from Tibet and China, G. sino-ornata produces 6-centimetre long electric-blue trumpets from September to November, and it has parented many of the good autumn-flowering varieties, which range in colour from pale baby blue to rich, glossy indigo.
Plant collectors of the early 20th century became rather obsessed with Asiatic gentians, which isn't surprising, since the piercing-blue flowers make them stick out, jewel-like, on the scrubby slopes and pastures of the Himalayas. Scottish botanist George Forrest found Gentiana sino-ornata in Yunnan, and, when it bloomed for the first time in Britain – in the Royal Botanic Garden Edinburgh – people flocked to see it. Enjoy these blue beauties in your own garden by giving them the moist, free-draining conditions they love and in which they are easy to grow.
What are the best autumn gentians to grow?
There is a wide range of hybrids, which are often the offspring of the showy Chinese gentian (Gentiana sino-ornata), in every shade of blue. Growing a range of blue hues gives a great effect en masse. 'Strathmore' is a pale sky-blue form; 'Blauer Kobold', 'Braemar', and 'The Caley' are mid-blue shades of ultramarine; while 'Faszination' and 'Sensation' are deep lapis blue.
Where should you plant autumn gentians?
Choose a sunny site that has retentive, well-drained soil. Add leafmould or compost to boost retention and drainage, if necessary. Since they are low-growing plants that you'll want to look closely at, and because they grow in an expanding mat, they are best at the edge of borders, perhaps dressed with gravel, since this conserves moisture, wards off slugs, and looks good.
Neutral to acid soil is essential; Gentiana sino-ornata and its hybrids loathe lime, so if your soil is alkaline, plant them in pots with ericaceous compost. The lax stems grow in a spreading prostrate fashion, so autumn gentians look great in stone troughs, which can often be found in reclamation yards.
How do you care for autumn gentians?
In its preferred conditions, Gentiana sino-ornata is a doddle to grow.
Drainage and moisture: autumn-flowering gentians enjoy free-draining, moist soil because their natural habitat is the damp mountain meadows and open forest and scrub of the Himalayas, where the annual snow melt runs around their roots.
Sun: in the wild, autumn gentians grow in full sun, but their feet are always damp. So, if you live in a region with good rainfall (such as Dartmoor or Scotland), a south-facing open sunny position is great; otherwise, plant in a west-facing spot, ensuring that the earth is retentive during summer. In a garden that suffers from drought, a waterside spot or a site in semi-shade is preferable.
Acid soil: G. sino-ornata turns its nose up at lime, so a neutral to acid soil is vital. If watering gentians in containers, never use hard water from the tap; either filter it and add a drop of vinegar (to alter the pH) or use rainwater.
Food: mulch with compost or well-rotted leafmould each spring. You could also give them a dash of blood, fish, and bone.
Propagating: sometimes the prostrate rooting stems make new plants ('thongs') by themselves. But to keep the gentians floriferous and make new plants, lift and divide every 2 to 4 years in early spring. Dig them up with a fork and gently prize them apart into smaller sections, before replanting.
Pests: if slugs and snails are a problem in your garden, dress the plants with gravel.
Foliage: G. sino-ornata is semi-evergreen. During winter, don't be alarmed if parts of the plant look brown or orange. This is the annual process of the leaves and stems dying back to a central rosette.
5 Other compact flowers for autumn colour
For cheering, bold colour when the temperature drops, these low-growing plants are ideal:
Ivy-leaved cyclamen – Cyclamen hederifolium produce magenta, pink, or white lantern flowers above ivy-like leaves in autumn. These Mediterranean tuberous perennials are very easy around trees and shrubs and will naturalise in humus-rich well-drained soil; they also do well in planters. Height: 12 centimetres.
Autumn crocuses – This group looks like spring crocuses, but flowers now, in autumn. They include the saffron crocus (C. sativus), as well as pale-violet C. speciosus and purple ‘Conqueror’. Plant in very well-drained soil in sun. Height: 15 centimetres.
Violas – Where they are not accessible to slugs and snails, the small cheering flowers of violas are a joy throughout the bleak seasons, often flowering for months non-stop. Teardrops F1 Mixed includes a range of colours. Grow in retentive, well-drained, rich soil or in pots, in sun or part shade. Height: 20 centimetres
Naked ladies – Producing violet, pink, or white goblets without foliage, Colchicum are a delight blooming through autumn leaves. C. autumnale is a single pink and ‘Waterlily’ is a double lilac pink. Plant in moist, well-drained, fertile soil in sun; wear gloves because these native cormous perennials are toxic. Height: 15 centimetres.
Winter daffodil – The common name of Sternbergia lutea is a misnomer, since it blooms in autumn and (other than its sunshine colour) looks more like a crocus than a daffodil. This Mediterranean bulb enjoys full sun and good drainage (at the base of a warm wall or half under a shrub to shield it from rain). Height: 15 centimetres.
Spring-flowering gentians
The bell gentian (or stemless gentian), Gentiana acaulis, hails from the Alps, where it dots the mountainsides with patches of sapphire in April and May. One of the easiest spring gentians to cultivate (if it likes your garden conditions), it is also the most widely available. It forms a clump of evergreen leaves that are topped with vivid-blue trumpets. 'Rannoch' (deep cobalt) and 'Krum Rey' (electric blue with a green throat) are two good hybrids.
In general, this spring form won't bloom as abundantly as the autumnal G. sino-ornata, but the flowers tend to be larger. Like its autumn cousins, it loves very well-drained, moist soil, in part shade or sun. The standard advice is not to plant G. acaulis in alkaline earth, but many gardeners report success on limey soils.
