Tackling large infestations of lords-and-ladies in a well-planted bed can be difficult. To get rid of it completely requires time and patience. Try the following non-chemical approaches:
- Digging up tuberous rhizomes regularly can help to limit spread of the weed but is time consuming and unlikely to eradicate it completely, as any missed fragments will regenerate. If undertaken ensure all weed material is destroyed and not added to home compost bins
- Laying opaque mulches can help to smother weed growth. These should be in place for at least two growing seasons. Where other plants are growing try a deep (15cm/6in) bark mulch instead
There is little recorded data on the chemical susceptibility of this weed but success might be had by applying SBK Brushwood Killer in spring when there is an abundance of leafy growth.
A systemic glyphosate-based herbicide (Round-up Ultra, Doff Glyphosate Weedkiller or SBM Job done General Purpose Weedkiller, Westland Resolva Pro Extra Tough Weedkiller) would also likely be effective, but several applications may be needed. To improve the uptake of glyphosate, bruise weed foliage with the back of a spade or by treading before treatment.
Inclusion of a weedkiller product does not indicate a recommendation or endorsement by the RHS. It is a list of products currently available to the home gardener.
Weedkillers for gardeners (Adobe Acrobat pdf document outlining weedkillers available to gardeners; see sections 1a and 4)
Chemicals: using spot and broad-scale weedkillers
Chemicals: using a sprayer
Chemicals: using safely and effectively
Weeds: non-chemical control