Blue Slate 40mm Bulk Bag

40mm Blue Slate – Premium Decorative Slate for Borders, Ground Cover and Landscaping

40mm Blue Slate is a popular decorative aggregate known for its striking blend of deep blue, plum and grey tones that create a bold, contemporary look in any outdoor space. Larger and chunkier than the 20mm size, these slate chippings are ideal for decorative borders, ground cover, rockeries and low-maintenance garden areas where a more textured, rugged finish is desired.

Made from high-quality natural slate, these chippings lie flat thanks to their natural flaked shape, helping to create a stable surface that stays in place with minimal movement. When wet, the slate darkens to a rich, almost charcoal blue, giving your landscape dramatic colour variation throughout the year.

40mm Blue Slate is a great option for gardens, commercial landscaping, wildlife areas and water features. The larger size is especially effective as a ground cover, reducing weed growth when used with a membrane and helping soil retain moisture around planting beds. It also provides excellent drainage, making it suitable for areas that need improved water flow or decorative drainage channels.

Supplied in bulk bags, our 40mm Blue Slate is clean, consistent in size and ready for use across a wide range of landscaping projects.

Key Benefits:

• Bold deep blue and grey tones for a modern decorative finish

• Larger 40mm size ideal for borders, rockeries and ground cover

• Low-maintenance and long-lasting natural slate

• Flat, flaked shape helps slate settle neatly and stay in place

• Colour intensifies beautifully when wet

• Helps suppress weeds and retain soil moisture

• Suitable for water features and wildlife-friendly gardens

• Supplied in bulk bags for excellent coverage and value

Typical Uses:

• Garden borders and planting areas

• Ground cover and low-maintenance landscaping

• Rockeries and feature garden designs

• Water features, ponds and streams (fish-safe once washed)

• Decorative drainage and dry riverbeds

• Commercial and residential landscaping

Installation Tips:
Lay to a depth of around 50–60mm for best coverage. Use a weed control membrane underneath for low-maintenance results. Rinse the slate after spreading to remove natural dust and reveal the full depth of colour. For pathways, consider the 20mm size instead, as 40mm slate is better suited to decorative and static areas.

Why Choose Us?
We supply premium 40mm Blue Slate sourced from trusted UK quarries. Clean, consistent and excellent for decorative landscaping, our slate provides a stylish, durable finish with reliable delivery and long-lasting performance.