The RHS believes that avoiding pests, diseases and weeds by good practice in cultivation methods, cultivar selection, garden hygiene and encouraging or introducing natural enemies, should be the first line of control. If chemical controls are used, they should be used only in a minimal and highly targeted manner. 

Cultural control

Eradicating the weed using non-chemical approaches can be difficult and requires time and patience. However where the weed occurs in beds and borders, these approaches may present the most effective and practical control:

• Regular light hoeing of seedlings soon after they appear will sever rosettes from their taproots and prevent flowering and seed production. Use a long-handled hoe to quickly tackle a border and a hand hoe for weeds growing near or between established plants. Non-flowering seedlings can be composted
• Applying organic mulches, such as bark chips, to affected beds and borders will prevent growth if applied to a depth of at least 8cm (3in). Opaque mulching films are also effective

Weedkiller control

In beds and border

The contact herbicide pelargonic acid (Doff 24/7 Fast Acting Weedkiller, Roundup NL Weed Control, Resolva Xpress Weedkiller) fatty acids (SBM Job Done Garden Ultrafast Weedkiller) or the systemic herbicide glyphosate (Roundup Fast Action) can be used in such situations to scorch off foliage. This should be done before plants produce seed. Take care if applying these non-selective herbicides between ornamental plants by covering them with plastic sheeting whilst spraying. Covers can be removed once the spray has dried on the weed foliage.

In uncultivated areas or around established trees and shrubs

SBM Job done Tough Weedkiller (ready-to-use only), SBM Job done Path Weedkiller (ready-to-use only) and Weedol Pathclear products containing glyphosate/diflufenican and can be applied once a season to natural surfaces where no plants are to be grown, and can also be applied under and around established woody trees and shrubs. This product kills off existing small green growth and prevents or checks developing growth. Check manufacturer’s recommendations before use to avoid damaging sensitive plants.

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.

Download

Weedkillers for gardeners (Adobe Acrobat pdf document outlining weedkillers available to gardeners; see sections 3a, 4 and 5). 

Links

Chemicals: using spot and broad-scale weedkillers
Chemicals: using a sprayer
Chemicals: using safely and effectively
Weeds: non-chemical control