Long Lasting Weed Killers
Treating weeds on areas such as gravel/shingle driveways, waste ground and under fencelines
Total weed killers can broadly be classified as either “contact” only or “residual” which gives a long lasting effect.
Contact weed killers only kill the weeds they come into contact with. Although sprayed weeds will die permanently, new weeds can emerge immediately afterwards. Many contact weed killers contain the chemical glyphosate and include well known brands like Roundup ProActive, Roundup ProVantage, Gallup Biograde Amenity and our strongest 5L glyphosate Gallup Hi Aktiv Amenity
Residual weed killers give longer lasting weed control by leaving a residue in the soil or substrate which continues to kill weeds after application for a number of months. The more persistent products may only need one timely application per year. Mixing a residual weed killer with a contact weed killer can give impressive results as the contact weed killer gives rapid knock-down of weeds, whilst the residual weed killer continues to keep the area clear of weeds.
Most residual weed killers should only be applied to a porous surface. This reduces the likelihood of the chemical running off and affecting non target areas.
Popular residual weed killers for porous surfaces are Paradise and Chikara. Both Paradise and Chikara weed killers are a very concentrated water dispersible granule formulations containing 25% w/w flazasulfuron for use as a non-selective residual herbicide on natural surfaces not intended to bear vegetation, permeable surfaces overlying soil and hard surfaces (railway ballast only). The label claims 4 to 6 months weed control from one application. Chikara is available in 50 g (covering ¾ acre). Paradise is available in either 50g or 150g. You can apply the mix using a knapsack sprayer.
Proshield is a pre-mixed driveway weed killer that includes glyphosate and a residual chemical. One 5L bottle covers nearly 2.5 acres (11,000 m2), is rainfast in 1 hour and can prevent weeds for up to 6 months.
For a non-professional alternative PathClear Liquid Tubes will also give long lasting weed control plus weed knockdown without mixing a separate weed killer.