This perennial spreads by seeds and creeping, fleshy white roots. The seeds are wind-blown from log upright seed-pods. From July to September, deep rose-pink flowers are produced.
The main way to keep weeds under control is constant vigilance, never allowing the weed to flower or seed and mulching.
Remove weeds by hand as soon as you see them
Spray with a systemic weedkiller that is absorbed through the leaves of the plant, 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