Horticulture experts are urging gardeners to act now to protect native bluebells from 'invasive' Spanish species

I can't be the only one who's noticed a significant increase in bluebells shooting up this spring? And in places that they most certainly have not been intentionally planted? This is likely because the majority are now Spanish bluebells, a far more invasive variety that is not as welcome for the welfare of our gardens.

As a result, one professional gardener is urging homeowners to check which type of bluebell is growing, to stop them taking over. “Spanish bluebells can spread more easily than our native species, so gardeners need to be aware of how quickly they can multiply," warns Chris Bonnett, plant expert and founder of Gardening Express.

They may not yet be officially registered on the government's list of invasive garden plants to avoid in England and Wales, but they are most certainly on a watchlist as they are spreading more rapidly, threatening the future of the nation’s beloved native blooms.

So, how do you know if you have Spanish or native English bluebells? We asked the experts to explain how to distinguish between the two species and what to do with the unwanted ones.

English bluebells vs Spanish bluebells: what is the difference?

Our resident gardener, Orpheus Alexander, warns: "The biggest issue with the Spanish variety is hybridisation; they cross-pollinate with the English bluebells and basically dilute the true native plants we have. The Spanish and hybrid seeds are much easier to spread, so they spread more aggressively and outcompete the English ones for sunlight, which then eradicates the English variety."

"Spanish bluebells were originally introduced as ornamental garden plants, but their ability to spread aggressively means they are now one of the biggest threats to native bluebells," Chris warns. “The biggest risk comes from gardens, where they may be planted for their beauty but can spread beyond boundaries through seeds, bulbs and garden waste if left unchecked."

While Chris warns of planting this bluebell variety, he is also aware that many homeowners may have the invasive plants growing in their gardens and not even know it. Before long, they'll quickly take over and outcompete native English bluebells, so he's encouraging homeowners to take a closer look.

They look incredibly similar, so how can you tell them apart?

"English bluebells droop over to the side, have a deeper violet/blue colour and a lovely scent," Orpheus explains. "Spanish bluebells grow upright, are lighter blue and omit almost no scent."

Chris Bonnett

Chris is the founder of the online garden centre GardeningExpress and has been in the horticulture industry for over 20 years. Whilst he was young, he combined his passion for the outdoors with the internet to deliver quality plants across the UK and Europe.

How to stop the spread of Spanish bluebells

“Gardeners play a crucial role in protecting native bluebells. Even a single garden population can establish in surrounding areas within a few years, so early identification and careful management can make a big difference,” Chris explains.

We touch on this lightly in our guide on what to do with bluebells after flowering. But in more detail, here's how you can help to stop the spread...

• Dig up bulbs carefully: "Spanish bluebells spread through underground bulbs, so removing the entire bulb is essential to controlling the plant."
• Dispose of plants properly: Like when getting rid of weeds, how you dispose of these invasive plants is key to stop further spread. "Never compost them or dump garden waste in the countryside. Bag plants and dispose of them via general waste."
• Avoid planting or sharing bulbs: "Even giving bulbs to friends or neighbours can spread the invasive species further afield."
• Monitor your garden: Make it a habit to monitor your garden each spring, because as Christ points out: "New plants can regrow from missed bulbs or seeds."
• Choose native alternatives: "Plant native bluebells or other UK-friendly spring flowers instead."

Should you remove Spanish bluebells?

In a bid to stop them from spreading, experts advise removing Spanish bluebells, but it is not a simple task. Which I would say is all the more reason not to let them get out of hand in the first place.

"Getting rid of Spanish bluebells isn’t easy and it’s not a one-time kill, so it’s important to manage your expectations," Chris explains. It may take multiple growing seasons to get rid of them. This is because Spanish bluebells can regrow from tiny seeds or small bulb fragments left in the soil. Even a bulb that has broken can easily regrow."

"The best way to get rid of them is to dig them out and since bulbs or seeds left behind can resprout, you’ll need to make sure you dig deep and wide. Follow the stem all the way down to the bulb cluster and remove all visible bulbs."

Chris warns that it's unlikely you’ll be able to dig out the entire plant on the first try. It's important to continue monitoring the area during the growing season and pull or dig out any new shoots straight away. Make this a regular task to tag onto your May essential garden jobs list – peak growing season.

"Disposing of bulbs and seeds is also crucial in making sure they don’t establish themselves again, so make sure you’re not adding them to any compost heaps. Bag them up and dispose of them in your green waste bin."

I don't know about you, but since I've been aware of the problematic bluebell situation, I'm becoming slightly obsessed with checking which species it is I'm seeing.

From what I'm observing, a lot of the front gardens I've been walking past are where I'm seeing the most Spanish bluebells, where none of them looks intentionally planted, which makes me think they are spreading more than ever. I now understand why Chris is keen for gardeners to act.