What is a Weed? Know Your Enemy

A weed is not a specific type of plant, it is simply an unwanted plant or a plant that is growing where it is not wanted. Once upon a time, this weed was a wanted plant and may have been introduced to the locality for a particular use – to look pretty, to be used in cooking or for culinary purposes. However, the plant has now become undesirable and has been labelled a “weed”.

Due to the fact that they are native plants and are ideally adapted to their local environment, weeds can take over an area of land or a garden very quickly. They are unwanted because they compete with wanted garden plants for nutrients in the soil, water, light and space and can push out more fragile plants. It is important to do regular weeding in your garden, to stop the growth and spread of these undesirables, so that your other plants can grow. You do not need any high tech or expensive equipment to get rid of weeds in your garden - just buy a small garden hand fork and some gardening gloves and use a washing up bowl or bucket to collect weeds in. For bigger, established areas, you may need a proper garden fork.

Be careful when disposing of weeds, you do not want any seeds to spread or fragments to fall on the soil and regrow.

When you are thinking about ridding your garden of weeds, you need to consider what type of plant the weed is, so that you will know when and how to deal with it:-

Annual – An annual weed germinates, matures, produces seeds and dies off in one complete season (year), leaving behind seeds to produce new plants. The seed supply can be vast – Groundsel plants can produce over 30,000 seeds! Seeds of annual weeds can lie dormant in the soil for many years. For example, the seeds of field speedwell can survive in the ground for over thirty years and even groundsel seeds can lie dormant for up to three years. Dormant seeds are “activated” by a change in conditions – turning over of soil, a change in temperature, light reaching them etc.

Annual weeds need dealing with before they have the chance to produce seeds. They are relatively easy to remove and control because their whole life cycle is over within one year.

Examples of annual broad leaved weeds are groundsel, common poppy, field forget-me-not, scarlet pimpernel and cleavers.

Examples of annual grass weeds are wild oat, barren brome and winter wild oat.

Biennial – These weeds take 2 full seasons (years) to grow enough to be able to produce seeds. Typically, during their first year, biennial weeds have a period of growth and of storing nutrients and food reserves. Then, in their second year, biennial weeds flower and produce seeds. After seed production they die off.

You need to remove these weeds in their first year before they can produce seeds. You can either treat them with a herbicide or uproot them by weeding.

Examples of biennial weeds are hogweed, giant hogweed, hemlock, spear thistle and evening primrose.

Perennial – Perennial weeds survive for many seasons because their roots and stems act as storage systems. They flower and produce seeds over many seasons, without dying off. Even if their top parts are removed by grazing animals, by picking or by weeding, they can regrow. You need to practise careful, heavy duty weeding to get rid of these weeds. Their whole root system must be removed and all stems/vines, otherwise they will regrow.

Examples of perennial broad leaved weeds are clover, bramble, nettle, daisy, dandelion, ground ivy, ground elder, mugwort and Japanese Knotweed.

Examples of perennial grass weeds are common bent, creeping bent, perennial rye grass and rough meadow grass.