Annual weeds complete their lifecycle within one year; growing, flowing, setting seed and then dying. They can be particularly troublesome as their rapid spread and growth can smother other plants and compete with them for water, food and sunlight. Annual weeds should therefore be destroyed before they have chance to produce their seeds. Once their seeds have been released, they may be scattered across the garden, escalating the problem.

Some annual weeds, such as chickweed and hairy bittercress can mature in a matter of weeks and produce seed, allowing them to have several generations in a season.

Although weed seeds are quick to germinate, if they become buried deeply they may lie dormant for many years. They will only germinate when the soil is moist, warm and exposed to light, so as soon as they brought to the surface during cultivation, they will begin to grow rapidly.

Annual weeds may be controlled by hand, mechanical or chemical means; however, shallow hoeing is usually the preferred method, as it quickly severs the roots from the stems to prevent further development.