We love our beautiful spring bluebells in Donegal, but they could be under threat

A carpet of native bluebells in full bloom is a sight that lifts heart and soul, and there is no shortage of places to witness this beautiful phenomenon here in Donegal. 

However, our native bluebell, with its delicate flowers and rich, deep colour, is vulnerable to invasive species. And with spring very much in the air, people are asked to keep an eye out for the invasive Spanish bluebell (Hyacinthoides hispanica), and to report any sightings. 

The invasive variety has a detrimental effect on our iconic native bluebell (Hyacinthoides non-scripta) in two ways. Firstly, it can cross-pollinate with the native bluebell and reduce the number of true native bluebells, and secondly, it spreads quickly, taking over the habitat.

Ireland’s National Biodiversity Data Centre (NBDC) describes Spanish bluebell as a robust medium to tall perennial herb native to west Iberian Peninsula and north Africa.

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According to an NBDC spokesperson: “This plant typically grows to about 40 cm tall. It has several tough, glossy, deep‑green leaves that are long and narrow, with blunt tips that gently droop after flowering. 

Flowers appear from March through to June, forming a spiral of striking mid‑violet to blue, bell‑shaped blooms on a firm upright stem. The petals open outwards, creating a bold display that may carry a faint, pleasant scent. 

“Below ground, the plant grows from bulbs and steadily spreads by underground runners, which produce new bulbs at their ends. 

“Fruit and seeds are produced between June and July. By the end of summer, the leaves die back completely, and the plant disappears from view above ground until the following spring.”

The Spanish bluebell may be found in woodland edges, hedgerows, roadsides, and church grounds, usually under shade. Seeds can be dispersed by wind over short distances. The plant can also spread by improper disposal of garden waste and via underground runners.   

It can easily be confused for native bluebell (Hyacinthoides non-scripta), but there are a few giveaway details.

Key Differences

The following information taken from the publication Guide to Ireland’s Regulated Invasive Alien Plant Species will help to distinguish the native bluebell from the Spanish bluebell and the hybrids that come about as a result of cross-pollination.

Leaf width: 

Spanish Bluebell - often greater than 15mm broad and up to 35mm

Hybrid Bluebell - usually broad, 10 to 35mm

Native Bluebell - narrow, usually less than 15mm but can be up to 20mm

Flower Shape:

Spanish Bluebell - broad bell shape petals flaring outwards

Hybrid Bluebell - broad bell shape with petals slightly curled backwards

Native Bluebell - narrow tube-like shape with petals curled strongly backwards

Pollen Colour:

Spanish Bluebell - pale to dark blue, pale green (not creamy-white)

Hybrid Bluebell - pale to dark blue, pale green (not creamy-white)

Native Bluebell - Creamy-white

Anther Colour and Position:

Spanish Bluebell - usually pale to dark blue and fused to bottom of petal

Hybrid Bluebell - pale creamy-blue, occasionally creamy-white and pink flowers and fused to middle of petal 

Native Bluebell - usually creamy-white and fused to top of petal

Flower arrangement on spike:

Spanish Bluebell -  flower spike usually still and upright with flowers spiralling around the stem. Erect when in fruit

Hybrid Bluebell - flowers spiral around the stop and often droop slightly to one side. Erect in fruit

Native Bluebell - flowers droop from one side of stem. Erect in fruit

Scent in warm weather:

Spanish Bluebell - none to faint scent

Hybrid Bluebell - none to faint scent

Native Bluebell - strong, sweet scent

Reporting

The Spanish bluebell is on Ireland’s First Schedule list of Invasive Alien Species of National Concern. It is therefore illegal to import, sell, grow or release this species. People are asked to report sightings via the online form  

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Further information on invasive species and their impact can be found at invasives.ie