Pumice
Pumice is a 5 to 10 mm volcanic aeration grit used in place of perlite. It keeps air and drainage in a potting mix or living soil and, unlike perlite, it does not crush or break down, so it suits soil that is recycled grow after grow.
At a glance
- Type: media, mineral aeration
- Grade: 5 to 10 mm
- Use for: aeration and drainage in potting mix, living soil and no-till beds; perlite replacement
- Rate: 10% to 30% of most soil mixes for vegetables and flowers
- Bulk: 500 kg and 1000 kg; email store@seaclifforganics.nz for a quote
What it is
A light, porous volcanic rock screened to 5 to 10 mm. It is the aeration in our Living Soil v2 and Superior Potting Mix.
What it does
- Its pores and the gaps between the grains hold air in the mix and let excess water drain, so roots get oxygen.
- It is a hard rock, so it keeps its shape through repeated mixing and recycling where perlite breaks down to dust.
- Growers soak pumice in a nutrient or compost tea before use, in the same way as bio-char, so its pores start off loaded rather than empty.
How to use
- Use 10% to 30% pumice by volume in most soil mixes for vegetables and flowers.
- Recommended with Potting Mix and other soils where you want more air and drainage.
- Optional: soak in a nutrient tea before mixing, as you would charge bio-char.
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Handling and storage
- Wear a mask to avoid inhaling particles and open the bag in a well ventilated area.
- Wear gloves and eye protection, and wash hands after use.
- Once opened, keep the bag sealed and dry.
Shipping and returns
We ship nationwide across New Zealand. Orders are usually dispatched within 2 to 4 business days and rural delivery can take longer. Faulty or damaged items are repaired, replaced or refunded under the Consumer Guarantees Act. Unopened products can also be returned within 30 days for change of mind.
