Have you noticed lots of pretty nodding white flowers in the parks and verges of Penarth this spring? They look a lot like white bluebells. But if you look closely, these flowers have a thin green line running down the middle of each petal. These are three-cornered leeks or three-cornered garlic.
We’ve noticed a lot of these growing in the Kymin recently. Pretty as they are, we are working to stop them from spreading and to eventually remove them from the park. This is to help nature thrive. That might sound a bit counterintuitive, but read on to find out why we’re doing this.
Three-cornered leeks look a lot like white bluebells, but notice the distinctive green lines running down the petals.
Schedule 9 species
The three-cornered leek is classed as an invasive non-native species in the UK. There’s nothing inherently wrong with non-native species. There are plenty of them in our parks and gardens, and lots of them are very useful. But some cause a bit of a problem, and can be harmful to the rest of the natural world around them. If they spread very quickly and widely, they can outcompete other species, and eventually change the habitat for the other forms of life in the area. We might see lots of pretty white flowers, but other plants and animals will have lost their homes.
In fact, the three-cornered leek is a ‘Schedule 9 species’. That means it’s listed in Schedule 9 of the Wildlife and Countryside Act as an invasive non-native plant. That puts it in the same class as Himalayan balsam and Rhododendron. It’s illegal to plant these species or cause them to grow in the wild. Something worth taking seriously, then.
The Friends of the Kymin has recently been involved in drawing up a Biodiversity Management Plan with the Local Nature Partnership, the Vale Council and local ecology firm, Soltys Brewster. As part of this plan, we agreed that removing three-cornered leeks from the park should be one of the priorities for helping nature thrive.
Three-cornered leeks growing along the railings on Kymin Terrace lane.
How are we doing this?
We learned that three-cornered leeks are mostly spread by its seeds… They are carried by ants! We can’t stop the ants from doing this. But we can stop the flowers from setting seed. Our plan, then, from this spring and in the coming years, is to cut off the flowers before they set seed. This will help contain them.
This is a really simple way of stopping them from spreading, and an easy job for community volunteers to get on with.
Eventually, we would like to remove the population of three-cornered leeks from the park, not just stop it from spreading. Over the next five years, we will dig up the bulbs in sections in spring. This is hard work, so doing it in sections over time will make it more manageable.
When we cut the flowers, we will also try to cut the leaves of the growing plants at the base. This won’t remove the plants immediately, but it will rob them of energy. If they don’t have leaves, they can’t photosynthesise and they can’t send down energy to their bulbs to store over winter. As a result, the shoots will be much weaker next spring.
So, by following these steps we’ll help biodiversity flourish in the park: removing the flowers and leaves of all three-cornered leeks every year, and digging up the bulbs in sections over the next five springs.
If you’ve got these flowers in your garden, these are steps you could easily follow too.
Three-cornered leeks at the edge of the meadow.
Giving back to nature one mouthful at a time
In case you were wondering – yes, the three-cornered leek is closely related to leeks and garlic. They are also edible. You can munch away on these plants and be happy that you’re doing something good for nature.
Do take care that you haven’t mistakenly picked another plant though. Some bulbs, bluebells included, are poisonous. How can you be sure you’ve got the right one? The clue is in the name. Two, in fact. It smells a lot like leek or garlic, and the stem is triangular (has three corners!) Remember those green lines down through the petals too (see the pic above). White bluebells don't have these.
They are delicious in an omelette, and the flowers look great in a salad. Let us know what you’ve done with yours!
