The old idiom, "an ounce of prevention is worth a pound of cure," applies to brick pavers as well as it does to health. Weeds quickly take root in soil and sand between pavers, and algae and lichens advance upon paver surfaces where they dine on minerals in the bricks. Preventing this from happening, keeps your walkway, driveway or patio looking nice and neat, while alleviating the danger of slipping on slimy algae or tripping over weed growth. A combination of methods is your best arsenal in the weed wars.
Sweep brick pavers weekly with a stiff broom to prevent the build up of dirt and plant detritus, which provide a growing medium for weeds. Sweeping also helps remove weed seeds and germinating plants.
Wash the area with soapy water once a month, using a broom to scrub the surface clean of ingrained dirt. Rinse with clean water from a bucket or garden hose. Direct the water away from lawns, garden beds and other planted areas.
Add an equal part of household bleach to clean water. Apply the solution to the brick pavers every two or three months, taking care not to splash plants or spill any solution on planted areas or lawns. Keep a bucket of clean water on standby for rinsing in case of accidents.
Heat joins between pavers with a flame gun every two weeks to kill germinating weed seeds. Hold the gun so that the flame is 1 or 2 inches above the bricks.
Apply a pre-emergent weedkiller, such as imazapyr, to prevent weed growth. Spray on a sunny day when temperatures are higher than 60 degrees Fahrenheit, or according to the manufacturer's instructions. Take care not to spray adjoining lawns or planted areas of the garden.
Apply a paving sealant to brick pavers that are less than 3 months old. Pavers must be completely clean and dry and should show no trace of surface salts. Check that no rain is forecast for 24 hours and that no sand is missing from the joins between pavers before applying.