Credit: David Foley
Echium pininana
Background and story
The Giant Tree Echium (Echium pininana) is a dramatic biennial native to the Canary Islands, where it grows in open, sunny habitats on volcanic soils.
It forms a dense rosette of soft, silvery-green leaves in its first year, followed in its second year by an extraordinary tall flowering spike, often reaching 3–5 metres, covered in masses of small blue to violet flowers.
Its vertical form and sheer scale make it one of the most visually striking plants that can be grown in temperate gardens, closely related to but more imposing than Echium wildpretii.
Did you know?
It is one of the tallest “biennials” you can grow. Despite living only two or three years, it can reach 3–5 metres or more in a single flowering season, with the spike sometimes growing several centimetres a day.
Hardiness and conservation
The recorded RHS hardiness rating is H3, which means this plant is generally hardy in coastal and relatively mild districts, especially where drainage and shelter are good. Local hardiness always depends on local shelter, drainage, winter wet, salt-laden wind and the plant’s age and establishment.
The IUCN Red List status recorded here is Endangered (EN). This places it in a threatened category, with a very high risk of extinction in the wild. The assessment year recorded in the plant data is 2011.
Additional notes for Ireland and Britain
In Ireland and Britain, Echium pininana is marginally hardy but often successful in mild coastal gardens, particularly where winters are not severe and drainage is excellent. It prefers full sun and free-draining soil, and is commonly grown in gravel gardens or sheltered borders. As a biennial, it produces foliage in its first year and flowers in the second, dying afterward, but it can self-seed freely in favourable conditions, allowing a continuing presence. Young plants are particularly vulnerable to winter wet and frost, so some gardeners protect or overwinter them under cover during their first season.
From a conservation and hardiness perspective, Echium pininana is considered endangered due to its restricted distribution range in the Canary Islands. However, it is widely cultivated and often naturalised in suitable climates. In terms of hardiness, it tolerates light frost (around −2°C to −5°C) but is vulnerable to prolonged cold and especially wet winter conditions, which can lead to rot. Its success in Irish gardens depends heavily on microclimate, drainage, and winter protection, particularly during its juvenile stage. In an Irish context, it is a high-impact but short-lived plant, valued for spectacle rather than permanence.
Notable features
- It follows an all‑or‑nothing life strategy. The plant is monocarpic, meaning it puts all its energy into one spectacular flowering event and then dies completely afterwards.
- It is incredibly productive, making hundreds of thousands of seeds. A single plant can produce over 200,000 seeds, allowing it to self‑seed freely and reappear year after year in suitable climates.
- It is a major nectar source for pollinators. Each flower produces measurable nectar with high sugar content, attracting bees, butterflies, and moths in large numbers, often creating an audible “buzz” around the plant.
- In its native Canary Islands, it grows at altitude, which explains why it prefers cooler summers than many tropical-looking plants, making it better suited to Ireland than it first appears.
- It is endangered in the wild despite being common in gardens. The species is endemic to La Palma in the Canary Islands and listed as Endangered, mainly due to habitat loss, even though it is widely grown elsewhere.
Earlscliffe notes
Undoubtedly the most conspicuous plant at Earlscliffe is Echium pininana from the Canary Islands , which has naturalised itself in the garden and subsequently throughout the neighbourhood and across the Howth peninsula. The flowering spike of this rampageous exotic grows 5 cm/day between April and June and can reach a height of over 6 metres.
It is sometimes said that David Robinson introduced this plant to Ireland. While we are not certain that this is correct, there is no doubt that he helped to popularise and promote it.