Why Weeds Keep Coming Back In Your Gravel Driveway

Gravel has many benefits around homes, and it creates a relatively affordable driveway material that's also easy to install. In theory, gravel acts as a physical barrier against weed growth by depriving soil of sunlight that the plants need to grow, and it doesn't contain the weed seeds that organic mulches sometimes do. Yet constant weed management is critical to stop their spread -– even in gravel driveways. 

Pulling newly sprouted weeds by hand before they flower and spread is considered a foolproof way to get rid of weeds from gravel driveways. There are still several reasons why weeds may keep growing in your gravel driveway. While gravel may reduce weed growth, it can never prevent them 100%. Even though gravel naturally covers the soil that weeds can take hold, weed seeds can still spread through wind and water runoff. The seedsmake their way in between small rocks creating an environment for growth.

Gravel also has a reputation for retaining heat, which may be conducive to plant growth. These effects can encourage new weed growth, but they may also explain why you see signs of weeds popping up in your gravel driveway in early spring. It's possible for weed seeds to have been embedded in the soil beneath your gravel driveway and can stay dormant until ideal growing conditions occur.

Weeds are persistent, but this doesn't mean you will have to resign yourself to a weed-ridden driveway forever. You can take steps to control weeds before they take over. Looking out for new signs of weed growth is key to any management strategy. Be diligent about pulling weeds along the edges of the driveway, as these sneaky plants can easily spread underneath gravel to other areas. Raking is another easy way to help refresh and level the rocks while also decreasing the chances of new weeds taking root in accumulated debris (consider skipping traditional rakes for this job, though).

You might also consider adding landscape fabric underneath the rocks to create more protection. This method is much easier to do before you add new gravel in your driveway, but it's still possible to add the fabric if you're planning on refreshing the rocks and regrading the underlying soil. To maximize weed suppression in the landscape, the Colorado State University Extension recommends leveling gravel and other types of mulch in layers that are 4 inches thick. You can add slightly more to accommodate the heaviness of vehicles you have in a driveway.

As a last resort, you might use herbicides for controlling weeds. If you choose this route, follow all safety precautions and directions carefully before use. It's also best to identify the weeds in your gravel to ensure you're using the right product, and that no other vegetation is nearby.