The invaders stalking your beds
When we think of invasive plants, alarm bells might ring at the mention of Japanese knotweed or giant hogweed, but can the same be said about buddleia, bamboo or montbretia?
Yet these — and other — common plants will be coming under the spotlight at this year’s RHS Chelsea Flower Show (May 22-26), in a garden of invasive plants, created to highlight non-native species that ‘escape’ from gardens up and down the UK and the damage they can do once let loose.
These include montbretia, false Virginia creeper, Japanese rose, three-cornered garlic, buddleia and cotoneaster. BAMBOO There’s been a lot of bamboo planted over the years, thanks to its popularity in gardening makeover shows, says Hodgson. If they are left unchecked they can be just as damaging as anything else. BUDDLEIA “We have a massive problem with the butterfly bush,” he says. “It’s a real nightmare. Anecdotally, it causes more structural damage to buildings than anything else.” Plant a buddleia (inset) near to your home at your peril. If you see any seedlings which have taken next to the house, pull them out, he advises. MONTBRETIA “Leaving it alone it will spread like wildfire. In most domestic gardens it will out-compete the other plants in the flowerbed and when you get it into a wild environment, it does exactly the same thing.” You can dig the corms of montbretia up to keep it in check but don’t put it on your compost heap. One solution is to burn the corms, he says. AQUATIC PLANTS Pennywort and water fern are problematic, he adds. Reports of the invasive plant floating pennywort in rivers and lakes have reached a record high, officials are warning. JAPANESE KNOTWEED This is a massive problem, because if you disturb it and then leave fragments under new structures, it will grow back through an extension or a patio or into a conservatory. The RHS advises using professional firms to eradicate knotweed, warning that DIY attempts may not be successful. For more information on the RHS Chelsea Flower Show, go to rhs.org.uk