The other day I was watching Gardener’s World (CPD) and one of the presenters was showing how you can have a wildlife pond in any size garden by sinking a wooden half-barrel in the ground – a great idea !! click on the link below to wqtch the barrell pond.
https://www.bbc.co.uk/programmes/p09jbcl8
you’ll notice that he suggests putting Carex pendula on the edge of the barrel —- NO!!!!!!
Gardener health warning – I have had to dig out at least 40 plants of Carex pendula from customers’ gardens; Plant “zero” usually a gift from a non gardening relative – little knowing that in 10 year time the garden would be overrun by Pendulous sedge (Carex pendula).
Images below show how it can easily overrun beds and smother all other plants.
Another example of a plant that can run amok is the “Chameleon” plant, Houttuynia cordata. It looks lovely – but under that multicoloured exterior – the roots are invasive and will quickly spread..engulfing other plants. The bindweed like roots are brittle and break so trying to dig it out is tedious and time consuming; it mingles in with plants you want to keep so chemical control is usually not possible without damaging the “good” plants. If you want this in a graden – keep it in a container!!
Chameleon strangling roses 
chameleon dug up (white roots)
Before adding plants make sure you know what they are capable of – just like any living thing they want to spread and reproduce!
www.madgardencare.com 