No matter how well paving might be laid, and no matter how much was spent on quality materials, all paving requires some basic maintenance to keep it looking its best. Weed-free paving doesn’t exist, no matter what you’ve been told. Maintenance keeps paving in prime condition: lack of maintenance allows paving to deteriorate.
Weeds are just plants that grow in inconvenient places – like on your new paving that’s just cost you a fortune. There are two common myths regarding weeds and paving:
1 – Myth Conception – certain types of paving/surfacing are “weed-free”
2 – Myth Behaviour – weeds grow up through paving
Firstly, there is no such thing as a weed-free surface. If debris (dead leaves, grass, sand, bird poop,etc), is allowed to accumulate on a surface, it will only be a matter of time before some weed or other decides to set up base camp. And secondly, when properly constructed, weeds do NOT grow through paving. Weeds will grow into paving, by colonising the sand-filled joints or settling onto accumulated debris, but it is very very rare for weeds to grow through 200mm or so of pavement structure.
Weeds can usually be pulled off the surface of most paving, or scraped off. Where roots have grown down into the jointing, removing the weeds often brings away some of the sand, and this should be replaced as soon as the surface is clean. Partially-filled or empty joints are detrimental to pavement performance.
Keeping weeds at bay
Once a paved surface has been cleared of weeds, it makes sense to keep it clean and weed-free for the future.
1 Regular brushing
Regular brushing disturbs newly emerging weeds and gets them before they can fully establish themselves.
Look for products that have been specifically developed for use with paving or in gardens, rather than general herbicides, which kill everything. Those chemicals sold as suitable for paving or garden use tend to be slightly more selective and target the weeds without discolouring the paving or killing off adjacent lawns or bedding plants.
A good quality sealant will prevent weeds settling into the pavement structure. However, even the very best sealant cannot prevent the build-up of debris, and if this is allowed to accumulate on top of a surface, the weeds will quite happily grow, regardless of the sealant.