Premium Grade Horticultural Pumice 25 ltrs 1-2 mm

Pumice is a light, porous volcanic rock that forms during explosive eruptions. It resembles a sponge because it consists of a network of gas bubbles frozen amidst fragile volcanic glass and minerals. All types of magma (basalt, andesite, dacite, and rhyolite) will form pumice.

Pumice grades:

• 1-2mm (New)
• 1-7mm
• 4-20mm
• 7-20mm

What is Pumice?

Pumice is a lightweight, foamy volcanic rock. The bubbles in the matrix are brought about by rapid cooling and depressurisation when the lava is ejected from the volcano. Pumice provides an ideal balance between water-holding capacity and air-filled porosity, allowing aerobic conditions around roots while containing an adequate supply of water. The high surface area is ideal for root hairs to penetrate and gain good anchorage for stable plants. Our pumice is mined in the beautiful North Island of New Zealand, from a site near Lake Taupo, and it is characterised by its relative hardness and lightweight in comparison to competing aggregates.

Usage:

Use pumice for Orchid mixes, grades 7-20, which is particularly well suited for orchid cultivation, providing the balance of air and water combined with long life. Pumice will not rot or break down; it is less likely to wash out of the pot. For propagation, use the smaller grades 1-2 and 1-7. Hardwood cuttings can be stuck in 100% pumice. The variation in particle sizes allows excellent basal contact for the supply of water, yet the porosity maintains aerobic conditions around the newly formed roots. Slow-rooting species such as Conifers, Maples and camellias are particularly well suited to propagation in pumice. Cacti and Succulents need to be planted in an open and well-drained potting mix; pumice is ideal for this purpose. Mix 30% pumice with your preferred organic substrates. Pumice has been used extensively for green roof mixes where substrates need to be long-lasting, lightweight, free draining and moisture retentive.

Ideal For:

• Orchids.
• Cacti and Succulents.
• Bonzai.
• Propagation.
• Green Roofs.
• Long Life Potting Mixes.

Properties:

• Light Weight.
• Up to 90% Porosity.
• Inert.
• Clean.
• High Capillary Action.
• Low Cation Exchange Rate.