A perennial weed found in garden borders and in newly sown lawns. It spreads by seeds, which can germinate in the same year, or the deep tap root which can go down by 3m (9ft) and lateral roots that spread for up to 6m (19½ft). It has erect stems with wavy, spiny leaves and lilac flowerheads borne from June to September.
Control
The main ways to keep weeds under control is constant vigilance, never allowing the weed to flower or seed and mulching.
Remove young weeds by hand before they develop a deep tap root
For established weeds, remove as much of the root as possible
Regular mowing will help to eradicate them in the lawn
Spraying with weedkiller will do the job if the weeds are in the garden border.
Spray with a systemic weedkiller as this is absorbed through the leaves of the plant and the active ingredient makes its way through the cells of the plant down to the root. It kills these first and then the foliage starts to die off. In lawns you can use a weed stick, such as Elliott's Touchweeder which is brushed on to the weeds leaves without harming the grass. More than one application will be needed for this stubborn weed.