Weeds in block paving

I've done the annual pressure wash of the block paved driveway to get rid of the weeds.

The local merchants have silica sand to brush into the gaps.

Has anyone got any weed killing tips for block paving gaps?

 

Common or garden salt!

 

Is DE-icing salt a contender?

I have a full tub of the stuff.

I presume I fill a watering can with water, add some salt and sprinkle over the paving?

 

Yes any salt will do. Just mix it with the kiln dried sand and brush it in.

 

Splendid!

How many parts sand to salt?

 

I've never thought of such, and maybe its a proven winner, but wont the salt dissolve over time and leave the sand lower in the gaps?

 

Apply "Pathclear" after the sand has settled. It prevents weed seeds from germinating. It is also a weedkiller that kills weeds, but the anti-germination film is thin and lies on top of the soil, so if you disturb it e.g. by pulling weeds up or hoeing it, seeds can germinate again. The sand between slabs or bricks ahould not get much accidental disturbance.

It lasts some months. You might get away with one treatment a year plus spot treatment, but two treatments a year are more likely.

If you just want to kill weeds that have already grown, any own-brand glyphosate will do it, but will not prevent regrowth.

BTW pressure washing block paving tends to loosen it by washing sand out of the joints.

 

I tried the salt method. Got some table salt added to water and applied to a test area but it didn't impede weed growth.

I'll try Path Clear next.

 

I have never used salt as a herbicide. However my understanding is that you need a reasonably high concentration, a couple of spoons-full in a five gallon watering can won't be enough.

A quick search here brings up this
https://www.diynot.com/diy/threads/weedkiller.506599/page-3#post-4204445

Edit: Also no chemical works instantly. Most herbicides are glyphosate based and that takes a week or two at best, i.e. when the plants are growing well. In slow growing conditions it takes longer.

AFAIUI Pathclear is a mix of glyphosate and the filming-producing agent, so will take a while at this time of year.

 

As said ,strong weed killer, allow it to work.
I often use a wire joint scrubber after then top up any joints.