I tried to keep weeds off my drive for years - one method has finally worked

The weeds on my driveway have been the bane of my life for years. I have a block paving driveway made up of thousands of individual bricks - and most of the time every single one of them is surrounded by a hideous combination of weeds, grass and moss. When the driveway is free of weeds (which is almost never) it looks bright and lovely - and I love it. But when the weeds have taken over, it looks awful and I'm embarrassed to show my face on the street.

One neighbour even offered to sort it out for me then spent days clearing it of weeds, which quickly came back. We were both devastated. I've tried everything from painstakingly scrubbing around several thousand bricks with a wire brush (which had my back begging for mercy) to filling in the gaps between the blocks with setting sand and kiln-dried sand. I also tried vinegar after my neighbours kept telling me it's what the previous house owner used to do (though they did warn it left the street smelling like a fish and chip shop for weeks).

At one point, I was just the click of a mouse away from buying a fancy gadget which sets fire to weeds. It looks like a litter-picker but with a flame or very hot element on the end and I was actually very excited to give it a go despite the fact that it would clearly take hours to individually burn thousands of weeds - but I thought I'd try one last method before I did.

And I'm so glad I did. Not only did this method take far less time than any other, but it's been weeks since I did it and only a tiny number of weeds have cropped back up, whereas they'd previously always returned even worse than before. Here are the methods I tried to rid my driveway of weeds before finding the one that actually worked.

Scrubbing with wire brush

A good quality weed wire brush did a great job of getting in between every nook and cranny and shredding the weeds within, which came away fairly easily. However, it was very quickly apparent that I was not killing the weeds at their roots and that they'd soon grow back. It was also back-breaking work which took hours. I persevered and scrubbed every inch of my driveway. It looked fantastic - for about a week. My back hadn't even recovered by the time the weeds reappeared.

I used the wire weeding brush method more than once. On the second or third occasion, I realised I needed to do something to prevent weeds from being able to grow in the gaps between the bricks that remained and was advised to try setting sand. This is sand that you brush into the cracks then lightly water so that it turns hard like cement and doesn't allow weeds to grow through.

Kiln-dried and setting sand

It sounded great in theory. I don't know if I was doing it wrong but it didn't work out in practice. It became quickly clear that I would need a huge amount of it to cover all of my modest driveway. But much worse than that was that when I sprinkled water over a small test area of about ten square feet, it also set over the bricks themselves, giving them a hideous dull grey hue. They looked filthy and terrible.

I also used kiln-dried sand, a fine, dry sand that fills the joints and is meant to create a strong, interlocking structure that resists weed growth. It looked far better than the setting sand I'd used, but it didn't stop the weeds getting through.

Weed killer

It was obvious very quickly that this method would be incredibly inefficient, time-consuming and ultimately pointless. After buying a bottle of weed killer and starting to spray each individual weed by hand, I realised that I would need several bottles and hours of time to get it done. And I also knew that given it would only kill the weeds currently there, it would do nothing at all to prevent new weeds growing. The spray did kill the weeds it touched, but it was not the right solution for my problem.

Bleach

I was very hesitant about using bleach to kill weeds, mainly fearful of any adverse environmental consequences. The internet is full of warnings about using bleach as a weedkiller. The main reason for this was for its adverse effects on any soil nearby. This was not an issue for me as I was using it on a driveway with no soil anywhere near it.

But I still didn't like the thought of pouring gallons and gallons of bleach all over the floor. But another key reason for this was its efficiency. I would need a huge amount of bleach to cover the area. I also worried about how I'd wash the bleach off when it had killed the weeds. And, since the advice from gardeners online was that bleach does kill weeds on the surface but does not kill the roots, it seemed like it would be mostly wasted effort anyway.

Vinegar, lemon juice and boiling water

I did not try these methods because my colleagues had done the work for me. They tested four natural ways of killing weeds - to varying degrees of success. Phoebe Cornish applied vinegar to weeds and said "the weeds looked colourless and shrivelled within a few hours of soaking them in the vinegar solution".

She added: "And when I checked back the following morning, I was truly impressed with the effectiveness of this gardening hack. It's a great way to flatten and weaken weeds before pulling them out of the ground, but it doesn't replace the need to dig out the roots to prevent them from growing back."

Another used lemon juice but found it usless, saying: "If anything, the weeds seemed to have grown 24 hours later." And I can't even begin to imagine how you get enough lemon juice to kill weeds over a large area. You'd need your own lemon farm.

Another method tried was boiling water and, although she immediately "saw the dandelion leaves and flower wilt dramatically", the weed still remained 24 hours later because the root was not destroyed.

The winning method: salt

I had heard a lot about salt being good for killing weeds but the thing that swung it for me was another of my neighbours saying she had seen extraordinary results from using it. Not only, she said, did it kill weeds - it also stopped them growing back. As a gardener with a beautifully-presented house front and back, she was someone I knew I should listen to.

She wasn't the only one singing the praises of salt: "Salt really does make a great weed killer as it will kill just about anything that grows," National Garden Bureau member and Laidback Gardener, Larry Hodgson, told Homes and Gardens, though he added: "But [it's] so toxic it simply can't be recommended in most garden settings."

But not only does salt kill the leaves if applied by spraying but it would kill the roots if watered in. On some websites, people said salt "essentially sterilises" the soil "preventing vegetative re-growth". On another, someone wrote: "If you salt the soil, no plant will ever grow there again."

How to use salt to kill weeds

This sounded amazing to me so I went for it. I bought 20kg of rock salt from Amazon (which turned out to be an awful lot of salt - you can buy it here). I already had a pressure sprayer with a large capacity of at least 10 litres (you can see an example here).

The first method I used was to add a significant amount of the rock salt to the sprayer then I added several litres of warm water. I stirred with a large plank of wood to dissolve the salt as much as I could then I began to spray the weeds. As with several of the methods above, I realised this was going to take me a long time (though it was far quicker than individually spraying weeds with weed killer from a hand-held bottle).

So I decided I would just take the lid off the pressure sprayer and tipped the salt water mixture out over as wide an area as I could. With just a few refills of my large pressure sprayer, I was able to cover the entire drive fairly quickly. I added additional clumps of rock salt to particulalry weed-ridden areas around the edge of the drive, where lots of dirt and sand had accumulated over the years and the weeds were at their worst.

Within a few hours the weeds were shrivelled and looked very dead indeed. Admittedly, large parts of my drive were now covered in piles of rock salt or the white resin left behind by the salt water. But I simply washed this off a few days later with a power washer (a hosepipe would work just as well).

Most importantly, the weeds were unquestionably dead. And it has been several weeks since I tried this method and, while some new weeds have begun to grow, they have appeared at nothing like the rapid rate at which they previously returned. So it appears there is truth to the claim that salt makes the soil inhospitable to plants growing there.

You obviously wouldn't want to use this method in a garden where you want to kill weeds but keep other plants and flowers, as the salt would wipe out everything. But for a patio or driveway, it just might be the solution you are looking for.

My colleague, Angela, had the same results. When she tested salt as a weed killer, she said: "Nine hours later, the weeds were completely dead, so I was easily able to dig them out. I didn't use a fancy tool for this; a regular screwdriver sufficed. Curious as to whether the weeds would reappear, I checked back in on the area over the next two weeks, and no weeds seemed to have grown back."