The problem of grass and weeds sprouting between pavers begins when organic debris, like dirt and leaf matter, accumulates in the joints. This debris provides a fertile medium for airborne seeds to land and germinate, creating shallow root systems. Successfully clearing the area requires a two-part strategy: immediate removal of existing growth, followed by methods to prevent seeds from taking root again. This approach ensures a clean surface now and reduced maintenance in the future.
Physical and Thermal Removal Methods
Physical removal offers an immediate, chemical-free way to address overgrowth by manually extracting the grass and accumulated soil. Specialized tools, such as crack tools or stiff-bladed paver weeders, are designed with thin blades to scrape material deep within the narrow crevices. This scraping action removes the entire plant, including the root crown, and dislodges the organic matter that provides the growing medium.
Boiling water is a simple, non-selective contact killer that works by destroying the plant’s cellular structure through thermal shock. Pouring water directly onto the growth causes the foliage to wilt instantly as the heat denatures the proteins within the plant cells. While effective for small, young weeds, users must exercise caution to prevent steam burns or splash-back. Deep-rooted perennial grasses may require several repeat applications to exhaust the entire root system.
A more aggressive thermal option is flame weeding, which uses a propane torch to expose weeds to a quick burst of intense heat. The goal is not to incinerate the plant but to rapidly raise the internal temperature, causing cell membranes to rupture. This method is fast for larger areas and works best on young weeds. Safety precautions are required, such as keeping the flame away from dry debris and nearby desirable plants.
Applying Chemical and Natural Solutions
Commercial herbicides provide effective control, especially those that are non-selective and systemic. Non-selective formulas kill all vegetation they contact, making them suitable for paver joints where no desirable plants exist. Systemic products, like those containing glyphosate, travel from the foliage down to the root, ensuring a complete kill that prevents immediate regrowth. Always verify the product is safe for hardscaping to avoid staining or etching the paver material.
Natural DIY solutions rely on high concentrations of acetic acid to desiccate the plant tissue. Household white vinegar contains about 5% acetic acid, which is sufficient for small, young annual weeds. For tougher grasses, a horticultural-grade vinegar (20% to 30% concentration) is significantly more potent, causing a visible burn within hours by rapidly drawing moisture out of the plant cells.
The efficacy of vinegar can be enhanced by combining it with a surfactant, such as liquid dish soap, which helps the solution adhere to the waxy surface of the grass blades. Some DIY recipes also include salt, which acts as an additional desiccant, but this should be used sparingly. Excessive salt can alter the soil’s chemistry in surrounding areas if it washes out, potentially harming nearby landscaping. High-concentration vinegar should be handled with gloves and eye protection, as it is a strong acid that can cause skin burns.
Strategies for Preventing Regrowth
Once the joints are thoroughly cleaned and dry, the most effective long-term strategy involves sealing the gaps to create an environment hostile to new growth. Polymeric sand is a specialized mixture of fine sand and polymer additives swept into the paver joints. When lightly saturated with water, the polymers activate and bind the sand particles together, creating a hardened, semi-rigid joint. This material acts as a barrier, preventing new weed seeds from penetrating the joint and finding a medium to germinate.
Applying a specialized paver sealant across the entire surface and joints, after the polymeric sand has cured, is another preventative measure. This sealant creates a protective, water-repellent layer that reduces the paver’s porosity and helps lock the jointing material in place. Minimizing moisture and organic debris dramatically reduces the opportunity for moss and weed spores to take hold. Routine maintenance, such as sweeping or blowing debris off the paver surface, prevents the accumulation of organic matter.