
Gardener beware! 6 'nightmare' invasive plants that I always avoid – by expert Jane Moore
Here’s my blacklist of plants to avoid – counting down from controllable enthusiasts to the unruly thugs that will take over your garden, says expert Jane Moore

6: Bear’s breeches
With its big, bold and architectural foliage, topped with tall spires of flowers in summer, bear’s breeches, Acanthus mollis, has a lot to offer the garden border, especially if you give it some room to clump up en masse. But it just won’t stay put where you plant it. Instead, it pops up in other places, not too far from the parent plant, but these new roots are too deep to dig out completely, and, before you know it, up it pops again, choking and smothering smaller plants and generally taking over its section of the border.
What makes it a nightmare? It just won’t stay where you plant it and regrows from the smallest piece of root.
Invasion rating: 7/10
Plant type: Perennial
Containment potential: Possible, with determination.
Why grow it? It’s a drama, and bees love it; just plant it somewhere it can take over.

5: Plume poppy
Macleaya cordata, plume poppy, looks just great in the garden, with its broad, lobed, blue-green leaves catching the raindrops and standing 2m tall, topped in summer with pink plumes of soft flowers. But it’s a spreader, sending rhizomes off through the soil that have shoots popping up all over the garden in no time at all.
What makes it a nightmare? Let it run unchecked, and it will take over, smothering other plants.
Invasion rating: 8/10
Plant type: Perennial
Containment potential: Chop it back with a spade each season to keep it in a defined area. Regularly weed out new shoots as they appear.
Why grow it? It looks great. The flowers are good for bees and other pollinators.

4: Ivy
Ivy in all its forms has its uses. It grows quickly, covering the ground as well as vertical surfaces like fences and walls, clinging brilliantly without the need for wires or frames. With its glossy green leaves and dense growth, the common form, Hedera helix, and the larger-leaved forms, like Irish ivy, Hedera colchica, can run riot, rooting into the ground and even house walls as they grow, making them hard to manage and potentially damaging to stonework.
What makes it a nightmare? Let it run unchecked, and it will take over, so don’t plant it and forget it. Ivy is harmful to pets and people if eaten and can cause skin irritation and allergic reactions.
Invasion rating: 8/10
Plant type: Evergreen climber
Containment potential: Cut it back to a defined area regularly and plant it on its own - avoid mixing it with other plants. The variegated forms are easier to control as they grow more slowly.
Why grow it? Ivy looks great climbing over an old stump, and it makes excellent ground cover where it can be left to itself. It’s also a brilliant wildlife plant for birds, bees and butterflies, especially the holly blue butterfly.

3: Willow
Who doesn’t love a majestic weeping willow by a pond? Or maybe a little pussy willow with those adorable furry catkins, which is a great choice if you’re tight on space, right? Wrong! Willows just love water, which means they’ll home in on your drains in no time at all, blocking them up with their extensive root systems. That’s no surprise for the big trees, but you even need to watch out for the dwarf varieties close to buildings and drain systems. There are so many other lovely trees out there – just pick something else, like a birch or a Japanese maple – they’re a lot less hassle.
What makes it a nightmare? Their roots seek out watercourses and drainage systems, blocking them up and causing £s worth of damage.
Invasion rating: 8/10
Plant type: Tree
Containment potential: None. Plant something else, or, if you must have one, make sure you plant it well away from your house – and your neighbour’s!
Why grow it? Willows are very attractive and provide good habitats for wildlife.

2: Bamboo
Pick the right variety of bamboo, and you have a highly attractive plant with coloured stems and a tropical, jungle look. But some bamboos are highly invasive, growing aggressively and expanding way beyond their allotted space, sending tough shoots up from far beneath the ground, metres away from the parent plant.
What makes it a nightmare? Some types will produce shoots popping up all over the place, which are almost impossible to weed out, as they’re so deep.
Invasion rating: 9/10
Plant type: Evergreen perennial giant grass
Containment potential: Make sure you pick a non-running variety, such as Fargesia. Plant coloured stem Phyllostachys on poorer soil to contain their vigour. Use a root barrier when planting spreading varieties.
Why grow it? Bamboos are brilliant for giving a tropical or Japanese look to the garden. The taller forms make attractive screening for hiding fences and sheds.

1: Russian vine
There’s a good reason that Russian vine, Fallopia baldschuanica, is also called 'mile-a-minute plant', and that’s because it’s such a vigorous climber, quickly hiding tumbledown sheds, old tree stumps and anything else you want to screen from view. With its pretty white and pink flowers festooning the twining stems in summer, it’s the prettiest thug you’ll ever see. But be warned - it is a thug, so take care where you plant it, as it grows about 4m each year and will swamp anything within a wide radius.
What makes it a nightmare? With a growth rate of 4m per year, this could easily take over your garden, house and indeed life if you plant it unwisely.
Invasion rating: 10/10
Plant type: Climber
Containment potential: Almost impossible unless severely hacked back every year.
Why grow it? It’s very quick-growing and very pretty – there’s nothing like it if you need to hide something quickly. Bees and other pollinators enjoy the masses of flowers.

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