Flagstones, paving stones (aka "pavers") and brick really do make an elegant choice for driveway or patio build material, but they can often leave something to be desired when it comes to routine weeding ... unless you're willing to apply a little <em>pressure</em>.
Weeds and moss are deceptively tenacious creatures and like to sneak up in between paving cracks. They come on easy, pretending to be friendly, but by the end of the week the level of poison you need to handle the situation is more likely to kill you than them. Fortunately, there's a way to tackle the problem that doesn't have to involve a hazmat suit (or crawling around on the ground, for that matter).
The only tool you should need is a high-power <a href="http://www.atgstores.com/pressure-washers_2438.html?linkLoc=topnav" target="_blank">pressure washer</a> if you're removing weeds and moss. If you end up needing anything more after a couple of shots from the big guns - then you probably need bigger guns.
Pressure washers typically come in <a href="http://www.atgstores.com/electric-pressure-washers-too_2438_oa0176649.html?linkloc=catheader&gpid=839117" target="_blank">electric</a> or <a href="http://www.atgstores.com/gas-pressure-washers-too_2438_oa0176650.html?linkloc=catheader&gpid=741294" target="_blank">gas</a> varieties for home use and the power levels between them can vary widely. Pressure-washer power is measured in pounds per square inch (PSI) and can range from around 1,500 PSI to well <a href="http://www.atgstores.com/4001-psi-and-above-pressure-washers_2438.html?&option0=optionA=176655|10889~Valu" target="_blank">over 4,000 PSI</a>.
(WARNING: The preferred PSI will depend on whether you're washing pavers or brick, how well-seated the materials are and what kind of substrate you're using. Extremely high pressure can chip stone or even blow the rock out of the ground if it's loose.)
The directions are easy: secure the washer to a water source, turn on, aim at offending plant life and fire.
Once you've blasted the weeds into the netherworld you'll want to make sure they don't come back anytime soon. To do that, you can use a <a href="http://www.atgstores.com/sprayers_2032.html?linkLoc=topnav" target="_blank">sprayer</a> to easily and quickly put down a layer of liquid weed killer, or try a granular herbicide or soap salts by sprinkling over the pavers/brick and then sweeping it into the crevices.
You can also try an organic alternative made of oils, citric acid, sodium lauryl sulfate and the like, but these are usually best used on contact and aren't as effective in a preventative capacity. Even so, you may find more peace of mind using these options with more frequent cleaning rather than an herbicide.
<strong>A note on cleaning ...</strong>
If your problems extend beyond weeds and moss to actual stains, dirt and grime, you may want to apply a cleanser before pressure washing to get even more magic out of your hose job. You'll just want to make sure the cleanser suits the kind of material you're cleaning.
<a href="http://ourblog.atgstores.com/?p=4331" target="_blank">ATGStores.com</a> can help fend off an Attack of the Killer Weeds and is happy to offer options and ideas that don't require weed killer.