When properly installed polymeric sand is very weed resistant. There are many factors that can lead to early failure of the sand such as not getting sand deep enough into joints, applying too much OR to little water to activate, paver systems that hold too much moisture, hills, and a lot more.
Polymeric Sand has many benefits, however, the biggest drawback is that it can be easy to mess up, especially if you don't follow the manufacturer's instructions.
Weeds don't grow from beneath the stones. They grow between the stones when the jointing sand washes away leaving space for the seedlings to fall in. Here in a moist, dark setting, the conditions are right for weeds to germinate and grow. Even a couple seedlings can quickly spread across your patio floor.
You can choose to fill the cracks between pavers with a polymer sand. This filler, once wet with a hose, turns hard, almost like mortar. It will make it tougher for weeds to take root. Or, plan to seal the patio once it's complete.
Polymeric sand is the most popular and useful filler used under brick pavers. It is a mixture of fine sand, adhesive and is most widely used in paver joints. Typically, polymeric sand lasts for up to 10 years. But if you use high-quality polymeric sand, it can last for approximately 15 years.
Simply boil the kettle, or heat up some water in a pan, and then pour the boiling water into the gaps between the paving slabs to prevent weeds from growing. Pouring boiling water onto weeds can also make pulling them out easier. The soil and roots soften up and do not cling as stubbornly to the earth.
When looking for alternatives to polymeric sand, you will also want to find high quality materials. There are other products, such as EnviroSAND, EnviroSTONE and EnviroPATH on the market that are able to stop water erosion from occurring.
The Problem With Polymeric Sands & Water Mitigation
Most polymeric sands don't drain water which meant small stones were used to fill the joints between the interlock. For driveways, this solution isn't a big issue but near a pool or patio, people prefer the smooth uniformity of polymeric sand.
Epic Fail #1: Too much or too little watering.
Using too much water can cause the sand to wash out of the joints. On the contrary, using too little can result in the product not setting up properly. Hazing can also occur if sand residue isn't fully washed off the surface of the pavers.
Weedblocker is a specially formulated polymer modified joint sand used with pavement systems utilizing segmental concrete pavers, clay pavers or natural stone; concrete slab joint applications or filling gaps between segmental retaining wall blocks. Weedblocker becomes activated when combined with water.
You can add normal builder's sand to the joints but weeds often find their way through this. The best solution, if you want to use this method, is to use a specialist product that is designed to stop weed growth. Joint filling sand. One example of this would be the Dansand Joint Filling Sand.
Prevent Weeds with Polymeric Sand
If you're wondering how to stop weeds growing between slabs, look no further than polymeric sand. This joint filler, for use with patios and block paving, provides a solid seal between the pavers that helps stop weeds from growing and damaging your whole patio.
Installing polymeric sand on a damp or wet surface could cause the sand and polymers to stick to the surface and become difficult to remove. After installation, a hard rain on polymeric sand that has not fully set up could result in polymeric sand all over the top of the pavers.
If remov- ing polymeric sand, a hot water pressure washer will help to soften up the binders in the sand. Any tough to remove hardened areas, may require mechanical means to clean the joint. Take caution with natural stone or thin style pavers and be sure to avoid disturb- ance of the bedding sand underneath.
Any excess polymers and sand should be rinsed off of the project surface. Go over your pavers again with a leaf blower to blow any excess water and sand off of the surface of your pavers. Work in small areas to be sure you remove as much standing water and/or sand as possible.
No, new product won't adhere to the old. You have to remove the old polymeric sand and then apply fresh product for the best result. How to replace polymeric sand between pavers? Inspect the pavers to make sure the sand in the crevices is at least 1/8″ below the top of the pavers.
Traditionally, concrete paver manufacturers have recommended waiting at least 90 days after polymeric sand installation to apply a protective sealant to a paver surface. Nowadays, a 30 day delay is sufficient to allow the evaporation of any remaining natural efflorescence contained in the pavers.
Using too much water can cause the joint to over-saturate and result in polymer washout, mushy sand, and a weak bond. It can also result in excess sand spreading onto the surface of the pavers, which is both hard to remove and an eye sore.
Polymeric sand cures by drying. And in order to fully set, it needs to dry out completely. If your polymeric sand didn't harden up, it's pretty much guaranteed there's a moisture issue. If the joints remain wet after the installation, they will remain soft until they dry.
Moss. CasaScapes polymeric sand will not cause nor prevent moss, mold or mildew. Moss, mold and mildew are caused by certain on-site conditions including excess moisture, shade, absence of ventilation, inadequate cleaning or maintenance, presence of soil or other organic debris left on the product.
Polymeric sand relies on a chemical reaction to harden it into the joints between your paving stones. Once it hardens, it is permanent.
Weeds start growing in the cracks of your paver patio when the joints are not properly filled with polymeric sand, or if that polymeric sand has weathered out of the joints over long periods of time. What happens is the joints fill up with dirt, and the weeds grow in the soil that has washed in the joints.
Power or pressure washing will clear out the weeds from a Cobblelock block paving driveway or path, so they are gone ... but only for for a short time. But although the surface looks good when we leave a customer's property, neither softwashing nor power or pressure washing actually kills the weeds.