Remove Moss from Your Terrace with Vinegar and Bicarbonate of Soda

What many people find irritating can be sorted with a simple trick from the kitchen.

Anyone with patio slabs, concrete flags or garden paths outdoors will recognise the issue: as soon as winter is over, a green film starts spreading. It looks unkempt, makes the surface dangerously slippery, and old-fashioned scrubbing usually only buys you a short break. Yet the most effective helpers are often already sitting in the kitchen cupboard - and they cost next to nothing.

Why moss clings so stubbornly to terraces

Moss thrives in damp, shaded spots. Patio slabs, driveways, garden paths, walls and steps hold on to water after rain. If a surface stays wet for a long time and doesn’t get much sun, moss settles in as if it’s at a spa.

Many people instinctively grab a stiff brush and start scraping and scrubbing. It can look better for a moment, but a few days later the green growth is back. The reason is simple: you’ve only removed what’s on top. In the fine joints and cracks, there are still spores and so-called rhizoids - root-like structures. They survive the attack and quickly start growing again.

Shop-bought chemical moss removers can work well, but they often contain ingredients that can put stress on beds, lawns and the life in the soil. If you’re trying to keep your garden healthy, you probably don’t want to pour an aggressive chemical cocktail over your paving.

"Moss always comes back when the cause - constant damp and shade - isn’t addressed and you only clean the surface."

Timing matters too. Treating on rainy days is pointless, because water dilutes the mixture and washes it away to the sides. Dry, overcast days are ideal: the solution stays on the surface for longer without evaporating too quickly in strong midday sun.

The powerful pantry duo: vinegar and bicarbonate of soda

Two kitchen staples are surprisingly effective against moss: plain white household vinegar and bicarbonate of soda (or baking soda). Dissolved in warm water, they create a cleaner that not only loosens moss but also makes regrowth harder.

Vinegar contains acetic acid. It penetrates the moss cushions and attacks their cell structure. Bicarbonate of soda is mildly alkaline and draws water out of the plants, especially around the rhizoids. Used together, you get a double effect: the visible growth dies back, and conditions become less favourable for new colonies.

A small squeeze of washing-up liquid makes it even more effective. It acts as a wetting agent, helping the solution cling to the plant surface instead of running off straight away.

What you need for your moss offensive

• White household vinegar (neat or lightly diluted)
• Bicarbonate of soda or baking soda
• Washing-up liquid (optional, but very helpful)
• Hot water
• Bucket or tub
• Stiff brush or yard broom with hard bristles

The same basic principle applies to other “nuisance plants” too: understand the conditions first, then treat them deliberately - rather than reaching for chemicals at random.

Step-by-step: how to get rid of moss properly

1. Prepare the surface thoroughly

Start by sweeping the entire patio. Leaves, soil, sand and loose dirt need to go. If you leave this debris behind, it will soak up the solution before it reaches the moss. The effort you put into sweeping pays off later when you start scrubbing.

2. Mix the solution

Fill a bucket with hot water. Add a generous splash of vinegar, then two to three tablespoons of bicarbonate of soda, plus a small squirt of washing-up liquid. Stir briefly - it will foam a little, which is normal. Once the fizzing calms down, the mix is ready to use.

3. Apply the solution and leave it to work

Pour the liquid liberally over all affected areas. Don’t miss joints, corners and steps. It’s fine if it forms little puddles - the more thoroughly the moss is soaked, the stronger the result.

"At least 15 to 30 minutes of contact time is crucial so that acetic acid and bicarbonate of soda can penetrate into the lower layers of the moss."

If you reach for the brush too soon, you significantly reduce the effect. With heavy growth, you can leave it on longer, as long as the surface doesn’t dry out.

4. Scrub and rinse

After the waiting time, scrub in circular motions with a stiff brush. In many cases, the moss will come away in thick clumps or even whole sheets. Then rinse with clean water - using a watering can, hose, or, if you have one, a pressure washer on a low setting.

When rinsing, direct the water away from flower beds, veg patches and lawns. The acid in vinegar can damage leaves and roots there, especially on young plants.

How to keep the terrace moss-free in the long term

Once the deep clean is done, the real job begins: setting up the area so moss struggles to re-establish. Water that sits for long periods is an ideal breeding ground. If rainwater doesn’t drain well or puddles keep forming, it’s worth checking the fall and drainage.

Shade is also a key factor. Overhanging shrubs and low branches block light from reaching the paving. A moderate prune lets sunlight hit the ground again - and moss really doesn’t like that.

• Channel rainwater away deliberately; avoid long-lasting puddles
• Prune shrubs and trees so more light reaches the ground
• Remove leaves and dirt regularly, especially in autumn
• Every two to three months, do a light vinegar–bicarbonate of soda treatment as prevention

A gentle pre-treatment in spring and late summer often keeps surfaces clean for years, without constant elbow-grease with the brush.

Risks, limits and sensible add-ons

As useful as this kitchen mix is, it still needs a bit of thought. On delicate natural stones - such as polished marble or limestone - vinegar can etch the surface. In those cases, test first in an inconspicuous spot.

Metal joints, zinc gutters or decorative metal elements also shouldn’t be left sitting in vinegar water for long. Brief contact is usually fine, but prolonged soaking can leave marks.

For very large driveways or heavily weathered slabs, a surface cleaner attachment on a pressure washer can make sense. A combined approach works well here: treat with vinegar and bicarbonate of soda first, then clean mechanically. This helps shift stubborn material embedded deeper down.

Practical examples from everyday garden life

If you have lots of ground cover plants or dense planting around the patio, you can indirectly encourage moss. Low, thick plants keep moisture around for longer, which can promote moss at the edges of slabs. Simply leaving a little more space between the bed edge and the paving can make a surprising difference.

Conversely, a narrow strip of gravel between the bed and the slabs can act as a “buffer zone”: water drains away faster, and soil and plant debris end up on the patio less often.

"A combination of small structural adjustments, regular sweeping and a simple home-made solution keeps outdoor surfaces clean and safe to walk on in the long term."

If you keep these points in mind, you won’t be staring in frustration at a green-coated patio each spring. Instead, you can calmly reach for the bucket and brush - and after one treatment, the problem is usually under control for many months.