The presence of weeds in paver joints is a common issue that affects both the appearance and the structural integrity of the hardscape. These opportunistic plants exploit the tiny gaps, and their roots can slowly break down the joint material. This breakdown leads to paver instability and shifting over time. Clearing paved areas requires a multi-step approach, moving from immediate removal to long-term defense.
Physical and Manual Removal Methods
The initial step in clearing a paver surface relies on mechanical removal, which is often necessary to expose the weeds for subsequent treatments. Specialized tools like joint scrapers or weeding knives are designed with thin, hooked blades to physically slice and pull out the weeds and the organic debris that allows them to take root. For larger areas, a stiff-bristled wire brush can be effective in scrubbing away smaller weeds and moss from the surface of the joints.
A pressure washer offers a powerful alternative for clearing large infestations, but it must be used with care to avoid damaging the underlying structure. Aggressive pressure can easily scour away the joint sand, which locks the pavers in place. To minimize this risk, the pressure should be kept within a range of 500 to 1500 PSI, and the wand should be held at least 24 inches away from the surface. Using a rotary surface cleaner attachment, rather than a focused jet nozzle, provides a more consistent and gentler cleaning action, preventing the erosion of the joint material.
DIY and Natural Weed Control Solutions
Several household items can function as effective contact herbicides. High-concentration horticultural vinegar, which contains acetic acid levels significantly higher than household vinegar (up to 20%), works by rapidly drawing moisture from the plant cells. This swift desiccation causes the weed’s foliage to wither and die, often within hours of application, but it typically only kills the top growth.
Mixing the vinegar with salt can enhance its effectiveness. However, salt (sodium chloride) should be used sparingly on paved areas, as it can leach into surrounding soil and sterilize it. Boiling water is another simple method that causes thermal shock to the plant tissue, rapidly killing the weeds by rupturing their cell walls. Care must be taken when pouring the boiling water to avoid splashing and potential skin scalding, and this method is best suited for small, isolated clusters of weeds.
Using Commercial Herbicides Safely
When manual or natural methods are insufficient, chemical weed killers provide a strong means of control, but their application requires specific safety measures. Herbicides are broadly categorized into contact and systemic types, which work differently on the plant. Contact herbicides provide a fast knockdown, killing only the parts of the weed they touch, which is effective for annual weeds but may not eradicate perennial roots.
Systemic herbicides are absorbed by the foliage and translocated throughout the entire plant, including the root structure. This makes them more effective for eliminating stubborn perennial weeds, though visible results may take several days. Non-selective herbicides will harm any green plant material they touch, making spot treatment directly on the weeds necessary to protect nearby landscaping. Always wear appropriate personal protective equipment, including gloves and eye protection, and apply the product on a calm, dry day to prevent wind drift or rain runoff from carrying the chemicals to desirable plants.
Long-Term Weed Prevention
The focus must shift to stabilizing the joints to prevent re-infestation. Long-term defense involves replacing the joint material with polymeric sand. This specialized sand contains polymer additives that, once activated by water, cure into a firm, cohesive material that locks the pavers together and forms a durable barrier against new weed seeds.
Proper installation of polymeric sand involves sweeping it deeply into dry joints and then wetting it according to the manufacturer’s instructions to initiate the hardening process. The application of a paver sealant adds an extra layer of protection by creating a surface film that repels moisture and organic debris. Sealants should be reapplied every two to five years to maintain their integrity. Ensuring that the paved area has adequate drainage is also important, as excessive moisture in the joints can break down even polymeric sand and create an inviting environment for weed germination.