Weed Control - Frequently Asked Questions
- Can I use a glyphosate weedkiller such as Roundup on my lawn?
- When can I dig up weeds treated with glyphosate weedkiller?
- My problem is ground elder creeping in from under my neighbour’s fence.
- How can I keep a piece of uncultivated ground weed-free?
- How can I get rid of bindweed climbing through my shrubs?
- Pathclear not working as quick as it used to.
- How do I get rid of trees or recently cut tree stumps?
- Are there any new ideas for killing Japanese knotweed?
Q. Can I use a glyphosate weedkiller such as Roundup on my lawn?
A. No. Glyphosate is not a selective weedkiller and does a great job killing grass as well as weeds. Instead of Roundup, use a weedkiller that is clearly labelled for use on lawns such as Verdone Extra. This contains ‘selective’ weedkillers that control the broadleaved weeds, but do not affect established grass.
Q. When can I dig up weeds treated with glyphosate weedkiller?
A. Leave the weeds and their roots undisturbed for at least two weeks to give the weedkiller time to get to all areas of the plant. It isn’t necessary to dig up the roots as they will die with the plant, so you can just cut off the tops after two weeks.
Q. My problem is ground elder creeping in from under my neighbour’s fence.
A. Treat in the Summer when the ground elder is growing strongly. First water the area so the weeds are actively moving sap around the plant. After a couple of days, choose a day that promises to be dry and spray as many weed leaves as you can reach with TumbleWeed or Roundup. Leave for at least two weeks undisturbed before cutting back the ground elder.
Q. How can I keep a piece of uncultivated ground weed-free?
A. Use Pathclear Season-Long or Pathclear Gun! Season-Long to treat the area at the beginning of the season. You won’t be able to plant up the area or sow seeds for at least 6 months.
Q. How can I get rid of bindweed climbing through my shrubs?
A. Wait until there are plenty of bindweed leaves showing. Spray as many leaves as possible with TumbleWeed or Roundup. Make sure you do not wet the leaves of your wanted plant.
Q. Pathclear not working as quick as it used to.
A. The original formulation of Pathclear, sold until 2004, contained among other chemicals, the fast acting ingredient paraquat. EEC legislation means we can no longer include this chemical in formulations for use in the garden. Paraquat showed effect on green tissue within 48 hours, but because this is no longer included, it can be a week or so before any visible signs of weed death are apparent. Even when diluted and applied correctly, Pathclear Season-Long can take two to three weeks before you see any visual signs that it is working. Despite a slower start however, our trials confirm that in the long term the current formulations are just as effective as the original.
Q. How do I get rid of trees or recently cut tree stumps?
A. Follow the instructions on the pack of Roundup Tree Stump & Rootkiller. Stumps should be treated immediately after cutting with a solution of this product painted onto the surface with a brush. For standing trees, cuts into the trunk at knee height need to be made and painted with the concentrate product.
Q. Are there any new ideas for killing Japanese knotweed?
A. A totally new product called Roundup Tree Stump & Rootkiller gives amateur gardeners the ability to kill Japanese Knotweed by applying the dilute product directly into the recently cut stems of this pernicious weed. A small pipette is included in each pack so that the diluted weedkiller can be directly placed into the stems of the recently cut weed. Full details of this application method are found on each pack of Roundup Tree Stump & Rootkiller. In late summer amateur gardeners are advised to cut the stems of the plants approximately 200mm above the base of the cane and 40mm above a node. Rupture the central stem tissue with a screwdriver and apply 10ml of a 20% solution of Roundup Tree Stump & Rootkiller into the hollow stem within 15 minutes of cutting using the 10ml disposable pipette supplied with the pack.
