7 Easy Ways to Kill Weeds in Winter

Why Weeds Still Grow in Winter

Most gardeners assume weeds stop growing once temperatures drop. They don’t. While warm-season annuals die back, a number of persistent species are perfectly adapted to cold, short days and damp soil. In fact, winter is their competitive advantage — with less competition from other plants, they spread faster than at any other time of year.

The worst offenders in UK winters include chickweed, which forms dense mats across bare soil, hairy bittercress, which germinates rapidly in cold conditions and fires its seeds explosively before you even notice it, and docks, whose deep taproots continue to store energy underground all winter long.

Perennial weeds such as bindweed, ivy, and brambles also remain a problem. Their root systems stay alive below the soil surface, ready to send up new growth at the first sign of a mild spell. If you want to learn to identify what you are dealing with, our guide to common UK weeds is a good starting point.

Hand Pulling: Use Winter’s Soft Soil to Your Advantage

Winter soil is consistently damp, which makes hand-pulling significantly more effective than in summer. Roots slide out of wet ground far more easily, and you are much more likely to extract the entire taproot of stubborn weeds like docks and dandelions.

The key is to pull weeds when the soil is moist but not waterlogged. Saturated ground compacts underfoot and damages soil structure. Wait for a day when the surface is soft but you are not sinking in.

For taprooted perennials, use a long-handled daisy grubber or a garden fork to loosen the soil around the base before pulling. Any fragment of dock root left behind will regenerate, so aim to get the full length. For shallow-rooted annuals like chickweed, a simple hand pull or hoe will do the job.

Dispose of pulled weeds in your green waste bin rather than the compost heap. Winter weeds often carry viable seeds, and a domestic compost bin rarely reaches the temperatures needed to kill them.

Mulching to Suppress Winter Weeds

Mulching is one of the most effective preventive measures you can take over winter. A thick layer of organic material blocks light from reaching weed seeds in the soil, preventing germination entirely. It also insulates plant roots, improves soil structure, and reduces moisture loss.

Apply a layer 5-8cm deep across beds and borders once you have cleared existing weeds. Suitable materials include well-rotted garden compost, composted bark, leaf mould, or wood chip. Avoid piling mulch directly against plant stems, as this encourages rot.

For a thorough guide to materials and application, see our complete mulching guide.

Mulching works best as a preventive strategy. It will smother annual weed seedlings and suppress new growth, but it will not kill established perennial weeds with deep root systems. Those need to be removed or treated with herbicide before you mulch over the top.

Using Weed Killer in Winter

Chemical weed control is still an option during winter, but it requires the right conditions. Glyphosate, the active ingredient in most systemic weed killers, is absorbed through the leaves and transported down to the roots. For this to work, the weed must be actively growing and the air temperature needs to be above 5°C.

In much of the UK, there are enough mild days between November and February to get effective results. Check the forecast for a dry spell with daytime temperatures of 8-10°C or above — these are ideal spraying windows. The weed killer needs at least six hours without rain after application to be absorbed properly.

Systemic weed killers are the only chemical option that will kill perennial weeds to the root. Contact herbicides, vinegar-based sprays, and homemade weed killers burn off the foliage but leave the root system intact. The weed simply regrows. For a full comparison, see our article on whether horticultural vinegar actually works.

If you are dealing with tough, established perennial weeds — bindweed, brambles, docks, ivy — a strong systemic weed killer is the most practical solution. Our Strong Weed Killer (£32.67) is a concentrated glyphosate formula designed for exactly this purpose.

Clearing Weeds on Paths, Patios, and Driveways

Hard surfaces present a different challenge. Weeds colonise cracks in paving, gaps between block paving, and edges where mortar has broken down. Winter rain and frost make this worse by opening up joints and creating new spaces for seeds to settle.

For block paving and driveways, start by scraping out weeds with a paving knife or stiff wire brush. Once cleared, re-sand the joints with kiln-dried sand to close the gaps and make it harder for new seeds to establish.

Glyphosate-based weed killer is safe to use on hard surfaces and is highly effective on path weeds when conditions allow. On areas where nothing is planted, salt can work as a short-term measure, though it should never be used near beds, borders, or anywhere with drainage into planted soil.

Pressure washing removes surface weeds and algae but does not kill roots embedded in cracks. Treat it as a cosmetic clean-up rather than a weed control method. Combining a pressure wash with a follow-up herbicide application gives the best long-term result.

Prevention: Setting Up for a Weed-Free Spring

What you do during winter directly affects how much weeding you face from March onwards. A few hours of preparation now can save significant effort later in the year.

The most effective prevention strategies for winter are:

• Mulch all bare soil. Exposed earth is an open invitation for weed seeds. A 5-8cm layer of mulch blocks light and prevents germination.
• Remove weeds before they set seed. One chickweed plant can produce over 2,500 seeds. Clearing winter weeds early breaks the cycle for the following season.
• Repair hard surfaces. Fill cracks in patios, re-point mortar joints, and top up kiln-dried sand in block paving to eliminate germination sites.
• Treat persistent perennials now. Applying systemic herbicide to active perennial weeds in late winter means they enter spring with damaged root reserves, giving them far less chance of recovery.
• Improve soil health. Dense, healthy planting in beds and borders leaves less room for weeds to establish. Adding organic matter over winter builds the soil conditions that support strong plant growth come spring.

For a broader strategy on long-term weed control, our guide on how to kill weeds permanently covers every approach in detail.

Frequently Asked Questions

Can you spray weed killer in winter?

Yes, provided conditions are right. Glyphosate-based systemic weed killers work whenever the air temperature is consistently above 5°C and weeds are actively growing. Choose a dry, mild day — ideally 8-10°C or warmer — and ensure no rain is forecast for at least six hours after application. Many UK winters offer regular windows that meet these conditions.

What weeds grow in winter in the UK?

The most common winter-active weeds in the UK are chickweed, hairy bittercress, annual meadow grass, groundsel, and shepherd’s purse. Perennial weeds such as docks, bindweed, and ivy also remain alive through winter, even if top growth slows.

Is it better to pull weeds or spray them in winter?

It depends on the weed. Annual weeds with shallow roots — chickweed, bittercress, groundsel — are easy to pull from damp winter soil and this is often the fastest approach. Deep-rooted perennials like docks, bindweed, and brambles are better treated with a systemic weed killer because hand-pulling rarely removes the entire root system.

Does vinegar kill weeds in winter?

Vinegar burns the foliage of weeds on contact, but it does not kill the roots. In winter, when growth is slower, regrowth after vinegar treatment may take longer — but it will still come back. Vinegar is best reserved for annual weeds on hard surfaces where you only need a short-term cosmetic result. For permanent control, a systemic herbicide is far more effective. Read more in our horticultural vinegar guide.

Should I mulch in winter to stop weeds?

Absolutely. Winter is one of the best times to apply mulch. A 5-8cm layer of composted bark, wood chip, or garden compost over bare soil will suppress weed seed germination, protect your soil from erosion, and improve its structure over time. Clear any existing weeds first — mulch prevents new growth but will not kill established perennials.

What is the strongest weed killer for winter use?

A concentrated glyphosate-based product is the most effective option for winter use. It kills weeds to the root, works on both annuals and perennials, and is safe to use on paths, driveways, and around (but not on) ornamental plantings. Our Strong Weed Killer is formulated at a higher concentration than standard retail products for more reliable results in cooler conditions.