40mm Black Slate

This eye-catching decorative garden stone is incredibly versatile, making it a great choice for a wide range of landscaping projects. When dry, Black Slate has a sophisticated dark grey tone, a highly sought-after shade for modern gardens and outdoor spaces. However, when wet, it transforms into a striking jet black, creating a bold and dramatic feature in any setting.

Sourced from North Wales, this natural Welsh garden slate boasts a smooth, flat surface with gently angular edges, enhancing its unique texture. Once quarried and recycled, it retains its authentic, natural qualities, making it a standout choice for garden designs.

Additionally, Black Slate is completely lime-free, making it a safe option for use in fish ponds and aquatic environments. As one of the larger decorative stone options available, it features 40mm-sized stones on average, perfect for adding depth and character to your outdoor space.

20mm Black Slate is also available here.

Black Welsh Slate Features

• Locally-sourced garden stone
• Great for garden borders
• Fish-Friendly; suitable for ponds

40mm Black Slate for Your Garden

As mentioned earlier, Black Slate is an incredibly versatile decorative stone that can enhance a variety of garden features. One popular way to use it is as a border around garden paving, creating a striking contrast between different landscape elements. Its deep black hue allows it to seamlessly blend into any existing colour scheme, making it a great addition to both modern and traditional garden designs.

Another stylish application is using Black Slate as a plant topper. Not only does this add an elegant finishing touch to flower beds and potted plants, but it also helps with drainage by allowing rainwater to filter through to the soil, keeping plants healthy while reducing weed growth.

For front garden landscaping, Black Slate is a fantastic choice for decorative features. It can be used for border or pathways leading to your front door, frame flower beds, or even create a low-maintenance slate garden that enhances your home's curb appeal. While the stones are safe to walk on, we wouldn’t recommend them for driveways, as they may shift under the weight of vehicles.

40mm Black Slate as a Water Feature

If you have a water feature in your garden, adding decorative stones like Black Slate can enhance its overall look and create a more natural, polished appearance. Sometimes, water features can feel incomplete, and just a few bags of Black Slate can transform them, blending them seamlessly into your landscape. Plus, Black Slate looks even more striking when wet, as it deepens into a rich, jet-black shade, adding a dramatic effect to your garden.

Garden ponds have also become increasingly popular as both a decorative landscape element and a haven for wildlife. Since Black Slate is lime-free, it is completely safe for use in garden ponds, meaning you can confidently add these stones without harming fish or aquatic plants. Whether placed within the pond or used to frame the edges, Black Slate brings a natural, sophisticated touch to any water feature.

How to Buy 40mm Black Slate

This stone can be collected for free at one of our depots in Wimborne, Bournemouth, Christchurch or Dorchester, or these garden stones can be delivered nationally to anywhere in the UK.

Available Pack Sizes

20kg maxi bags 

850kg bulk bags

How to Create a Garden Pond 

Adding a garden pond to your outdoor space comes with a variety of benefits. Not only does it create a calm and relaxing atmosphere, but it also attracts wildlife, providing a water source for birds and a habitat for frogs and other small creatures. If you're ready to take on the challenge of installing your own pond, follow our guide below for helpful tips and tricks!

1. Choosing the Right Location

Before you start digging, decide where your pond will be placed. Here are a few things to keep in mind:

Avoid positioning it directly under trees to prevent fallen leaves from contaminating the water. If this isn’t possible, consider a pond cover to keep debris out.

Choose a partially shaded area—this prevents the water from overheating in summer and provides a cool spot for birds and wildlife.

Ensure the ground is level to avoid water spilling over uneven edges.

2. Selecting the Size & Type of Pond

Next, determine the size of your pond and decide whether you want to buy or upcycle materials for it:

Pre-made plastic ponds can be found at garden centres and are ideal for both raised and ground-level ponds.

If creating a raised pond, you can use retaining sleepers lined with a plastic sheet or even upcycle an old tyre!

Use spray paint to mark out the pond’s shape and size before you begin construction.

3. Digging & Preparing the Base

If installing a ground-level pond, dig out the marked area to the correct depth.

Use Scalpings to fill any gaps and create a solid, level foundation.

4. Filling Your Pond & Adding Features

Now for the exciting part—filling your pond with water! You can also enhance it with additional features:

Consider adding a solar-powered water pump for a small fountain effect.

Introduce floating plants like lilies to create a natural look and provide shade for wildlife.

5. Decorating & Finishing Touches

The final step is making your pond look beautiful and natural!

Use Black Slate around the edges to help it blend seamlessly into the garden.

For a more dramatic effect, incorporate Rockery Stones and Boulders to create a feature rockery.

Add aquatic plants or even a wooden bridge for an extra touch of charm.

Important Note

Since our Decorative Stones are naturally sourced, there may be slight variations in colour from batch to batch. If your new stones appear dusty upon arrival, simply hose them down to reveal their true colour.

Enjoy your new wildlife-friendly, tranquil garden pond! 🌿💦  

Buy With Confidence

• Our 40mm Black Slate can be purchased in 20kg maxi bags or bulk bags that weigh approx. 850kg
• Not sure how much you need? Use our quantity calculator and enter your garden width and length to find out how many maxi bags/bulk bags you need! 
• Please select the bag size you'd like to buy and add to your basket 
• Our aggregates will either arrive on a hiab lorry that can be used to lift the stone onto your garden, or it will arrive on a pallet for kerbside delivery; depending on your address
• You can choose free collection from one of our Depots or fuss-free, home delivery.

A Service You Can Rely On

• Our reliable service offers prompt delivery to any area in the UK
• Stone Zone is a family-run business that has been well-established since 1998
• Our efficient customer advisors can help you with your purchase
• We pride ourselves on offering a range of affordable garden supplies 

Sample stones are also available in-store, please ask a customer advisor. 

A Delivery Service Tailored to You

Our top-rated delivery service is reliable and flexible to suit you, however, it can vary depending on where you live. Click here for more information on our delivery service and if your postcode is classed as 'local' or 'national.'

Any questions? Use our live chat to speak to an advisor, alternatively, you can fill out an enquiry form or call us on 01202 874207.