Scoria 25/7 16 Litre Bag

The perfect drainage product for any gardening or landscaping project. 25 to 7mm graded scoria is a lightweight but very strong aggregate which is perfect for use in draining gardens and lawns and in the Auckland region as a popular choice of backfill behind retaining walls and perforated pipes. Can also be used for decorative purposes.

Size: Screened through a 25mm down to 7mm screen and as such contains no fines.

Source: Naturally sourced within New Zealand’s North Island

Originally, scoria was used as a raw material for roading and building projects, however nowadays it is used predominantly as a drainage medium. Naturally sourced, scoria is a volcanic rock which is highly water resistant and thus is perfect as a water displacement medium. This is what makes it ideal as it effectively forces water away from the area and either guides the water back into the soil for nutrients or out and away from the plant roots. Screened at 25mm down to 7mm, it is typically a rich red colour with brown tones, however as it is naturally mined, this colour can vary from different shades of red and tones of brown. If you’re using it for decorative purposes please enquire before ordering. This product is perfect for the base of planter boxes that are close to the house, to assist water runoff, help prevent moisture buildup and damage to the outside of the house.

When using this product behind retaining walls, the use of a perforated plastic drainage pipe underneath the placed product will assist with the displacement of water. Usually backfilling a retaining wall you would use a drainage product like this. Scoria 25/7mm is ideal, its light and as a result puts minimal strain on the retaining wall and drains water fast. 

Its outer appearance is quite sharp with jagged edges and it is very porous – quite similar to pumice. For this reason, it is very light in comparison to other types of gravel. In gardening applications, it is best used as a base beneath soils in planter boxes and pots as, like mentioned above, it helps maintain a healthy flow of moisture through the soil. It can also be used as a decorative feature in the garden however, and can provide tones of colour to the yard. This product can also be used in low-lying wet areas for developing pathways. However we advise using a finer graded product, such as an All Passing 7mm grade (AP7) for this purpose.

Benefits:

• Natural water repellent. It helps to regulate the flow of water through pot plants and planter boxes, ensuring efficient drainage.
• Formed across centuries by rapid cooling of lava, it is a natural product and thus promotes heavy and rapid drainage.
• Although light, it is immensely robust and therefore can support a solid amount of weight when placed in or behind retaining walls or raised planters.

Although not as heavy as other gravel products, it is still solid and robust and appropriate footwear is recommended as the product can be quite sharp from the natural formation and mining processes.