When controlling weeds around your outdoor space on areas such as driveways, patios and lawns, it’s tempting to reach for a weedkiller spray. However, it’s important to think about the safety of everyone who uses the outside, including pets and wildlife. Harmful chemicals can be picked up on paws or fur when your pet walks over treated ground or brushes past sprayed foliage, and is then ingested when your pet grooms itself. Chemicals can also be washed off plants or the ground by rain or hose water, and collect in puddles that pets and wildlife may drink from.
How can I control weeds without chemicals?
There are a number of ways to tackle weeds that are completely pet-safe:
- Hand weeding. A range of weeding tools include long and short-handled hoes, and weeding knives. On a dry, breezy day, hoe off weeds by slicing them off at the soil’s surface and they’ll quickly die
- Weed burners. Electric or gas-powered weed burners are portable heat guns that burn off weed growth and are particularly good for tackling weeds in paving cracks, driveways and patios. Slow to use, so only really practical for small areas
- Pressure washing of hard surfaces gets rid of small weeds and moss, as well as clearing residues of soil and organic matter that would provide seed beds for weeds
- Boiling water – simply pour over to kill leaf growth (although it won’t kill the roots of perennial weeds like dandelions)
- Catch weeds before they seed. The old saying of “one year’s weeding is seven year’s seeding” holds true
- Quickly picking off seed heads before they spread will save hours of work later on
- To clear ground for planting, the easiest way to kill all weeds is to cover the soil with a light-excluding material for at least 12 months. Use weed control fabric, black polythene, thick cardboard or old carpet, weighing down the edges to keep out light
Which pet-friendly natural weedkillers available to buy?
There are several natural ingredients used in pet-friendly weedkillers, which can be used to kill annual weeds and the top growth of perennial ones. Although these are ‘natural’ products, keep pets off treated areas until the spray has dried.
Acetic acid is the active ingredient of vinegar and is available as ready-to-use weedkiller spray such as RHS Glyphosate Free Weedkiller, WeedKil Glyphosate Free Weedkiller and Ecofective Weed and Moss Killer. Acetic acid is effective at controlling annual weeds, but only kills the leafy growth of perennials, not the roots. Note that vinegar bought for culinary use isn’t sufficiently strong to use as an effective weedkiller.
Pelargonic acid is found in pelargoniums – better known as geraniums – and is a fatty acid that destroys the cell walls of the leaves. In Neudorff’s Weedkiller, it is combined with maleic acid hydrazide which is a growth regulator.
Are there any chemical weedkillers that are pet-safe?
Glyphosate is a widely available chemical weed killer and is described as safe for pets to use treated areas once the chemical is completely dry. However, it’s important to note that the World Health Organisation (WHO) considers glyphosate to be ‘probably carcinogenic’ to humans, and that glyphosate is the subject of several international court cases relating to cancer in humans. This could mean that, while glyphosate is considered safe for pets now, the advice may change in future.
Glyphosate kills both annual and perennial weeds, but you will need to reapply every four months to a year, to keep on top of weed growth. It comes in several formulations including gel, ready to use spray or concentrate to dilute and apply in your own sprayer. The most effective time to apply glyphosate is from mid-summer to autumn when plants are in active growth. Take great care to avoid getting the chemical on garden plants as it kills everything it touches.
A pet and wildlife-safe method of using glyphosate to control bindweed, which is a common garden weed, is to put canes in the ground for the bindweed to twine up. Then, simply slip the growth off the cane and, with roots still attached, bundle the leaves into a clear plastic bag, spray on the glyphosate and then secure the bag with a clothes peg and leave in place until the bindweed is completely dead.
Always follow all safety instructions. Where possible, apply any sprays late in the day when insects are less active to avoid risk of harm.