Weeds and problem plants.

It's often said that a weed is just a plant that is growing in the wrong place. However there are certain instances where you have a particular type of weed that you need to get rid of. For a general overview of controlling common weeds, see the weeds and weeding part of the gardening basics section of the site.

Table: A list of weeds and problem plants.
Plant Description Suggestion
Bamboo Whilst some bamboo can be small and decorative, most varieties can be invasive and become a problem if not controlled. Bamboo is often planted as a screen or visual barrier between neighbours, but left unchecked it may soon outgrow its original position and start to spread across the garden or under neighbouring fences.

It can be controlled with a in a non-chemical way with a sharp spade, cutting through the rhizomes and then digging up the roots with a garden fork. To treat chemically, especially if it's a large clump - cut all the canes down to ground level in winter, then in the spring apply a strong glyphosate based weed or stump killer (something like Roundup Tree and Stump Root Killer) to the new growth as it appears. Depending on the size of the clump that needs to be removed, repeated application of weed killer might be required.

If you do want to grow bamboo, choose a non-invasive variety that doesn't spread by rhizomes. Even then, I’d suggest planting it into a deep container that has been sunk into the ground.

Japanese knotweed Japanese knotweed is a rapidly growing, very invasive weed. Mature plants have reddish stems and heart shaped leaves.

It's not easy to get rid of but it can be done over time.

There are two main methods:
Continual cutting back to ground level will weaken the plant over time. Alternatively spray with a glyphosate based herbicide in early summer and late autum.

Trying to dig up the plant may leave parts of the root system, each part may then grow into a new plant.

Any plants that you cut down should be burnt, or placed into the centre of the compost heap (where the heat should kill the plant, bear in mind that if the heap isn't hot enough you may just be transplanting the Japanese Knotweed).

More information can be found on the Environment Agency web site.

Curiously, japanese knotweed doesn't grow very well in Japan.

Liverwort Liverwort are small, flat-leaved, flowerless plants that live in damp conditions in the cracks of patios and walls and on the surface of moist soil including lawns. They will only thrive in damp conditions, whilst chemicals can be used, removing them by hand and improving the drainage is a cheaper and longer lasting solution.

Other gardening pest and disease pages: